Sports Nutrition Primer—
By Debra Wein.
From NSCA’s Performance Training Journal, NSCA
-
Depending on the duration, intensity, and type of exercise you are performing, there are three stages where nutrition plays a role in performance —before, during, and after activity. One of the primary goals of sport nutrition is to optimize the availability of muscle glycogen, thereby insuring optimal performance.
Pre-Exercise Nutrition
Properly nourishing yourself before exercise should:
-Prevent low blood sugar during exercise.
-Provide fuel by topping off your muscle glycogen stores.
-Settle your stomach, absorb gastric juices, and prevent hunger.
-Instill confidence in your abilities.
Remember, fasting is detrimental to performance, and is strongly discouraged before exercise or performance. The pre-exercise meal should consist primarily of high carbohydrate, low fat foods for easy and fast digestion. Since everyone’s preferences for, and responses to, different foods are unique, it is recommended that you learn through trial and error what does and does not work for you. For example, some people respond negatively to sugar intake within an hour before exercise. The temporary “boost” that some people experience after eating foods with a high sugar (sucrose) concentration such as candy, syrups, or soft drinks actually causes an increase in insulin production which will be followed by a rapid lowering of blood sugar, and can lead to decreased performance. In addition, fructose (the sugar present in fruit juices) ingested before exercise may also lower your blood sugar and cause gastrointestinal distress in some people, but not others.
How much time should you allow before exercise after eating?
-Allow adequate time for digestion and normalization of blood glucose:
-4 hours for a large meal.
-2 – 3 hours for a smaller meal.
-1 hour for a blended meal, a high carbohydrate beverage (10 – 30%), or a small snack.
During Exercise
When an individual has been consuming a diet sufficient in carbohydrates, 60% or greater, there is enough energy present in the muscles to fuel workouts and other activities completed within 60 – 90 minutes. On the other hand, during prolonged, strenuous exercise lasting over 90 minutes, carbohydrate ingestion at
regular intervals during the exercise is beneficial2, 3. For example, consuming 8 ounces (1 cup) of a sports drink containing a 6 – 10 % carbohydrate concentration every 15 – 20 minutes can delay the onset of fatigue. This is equivalent to a rate of 0.8 – 1.0 grams of carbohydrate per minute or approximately 24 – 30 grams every half hour.
Post-Exercise Nutrition
When and what you eat after a work-out can have a serious effect on your recovery. Adequate recovery means that your muscles are rested, re-fueled, and ready to perform again, which is extremely important for people who exercise every day. Inadequate recovery can lead to chronic fatigue and a gradual decline in your performance. Be selective in what you eat after exercise; wise choices will help you recover quickly and enable your muscles to work better the next time around. For the fitness enthusiast whose workouts generally last less than 90 minutes, your main concern is to re-fuel with a well-balanced, high carbohydrate diet. However, if your workouts typically last longer than 90 minutes and are “exhaustive,” the timing of your meals is additionally important. Your body needs about 20 hours to replenish its fuel stores. Furthermore, this will only occur if adequate carbohydrate (approx. 500 – 600 grams depending on your body size) is consumed during this time2, 3. The first 2 – 3 hours after exercise are critical for you—don’t wait to eat.
For optimal glycogen re-synthesis, follow these target intakes during the 20 hours following a workout:
-Immediately after exercise (15 – 30 minutes): 75 – 100 grams carbohydrate.
-Within the next 2 – 3 hours after exercise: 100 grams carbohydrate.
-Every 4 hours thereafter: 100 grams carbohydrate.
For example, since 1 gram carbohydrate
= 4 calories, 75 – 100 grams = 300 – 400 calories. In practical terms, you could take in 75 – 100 grams of carbohydrate by eating:
-A banana and a bagel.
-1⁄2 cup raisins and a slice of bread.
-2 cups of orange juice and a cup of yogurt.
Current research also suggests that protein, when consumed along with the post carbohydrate fuel, can increase the rate of glycogen resynthesis and improve recovery1. A high carbohydrate beverage (10 – 30% carbohydrate concentration) can also be used as an immediate source of carbohydrate replenishment. These beverages can be especially useful after a workout in the heat when you may be more inclined to drink than to eat. However, high carbohydrate beverages are not complete foods; they do not contain all the nutrients your body needs for good health and top performance. If you use these beverages in your training regimen, make sure you follow soon after with a well-balanced, high carbohydrate meal, and plenty of fluids.
References
1. Koopman R, Wagenmakers AJ, Manders RJ, Zorenc AH, Senden JM, Gorselink M, Keizer HA, van Loon LJ. (2004). The combined ingestion of protein and free leucine with carbohydrate increases post exercise muscle protein synthesis in vivo in male subjects, American Journal of Physiololgy – Endocrinology and Metabolism, Nov 23.
2. Position of the ADA, Dietitians of Canada, and the American College of Sports Medicine. (2000). Nutritionand athletic performance. Journal of the American Dietetics Association, 100:1543 – 1556.
3. Rosenbloom C. (2000). Sports nutrition, A guide for the professional working with active people, Third Edition. Chicago; The American Dietetic Association.
About the Author
Debra Wein, MS, RD, LDN, NSCACPT is on the faculty at The University of Massachusetts Boston and Simmons College. She chairs the Women’s Subcommittee of the Massachusetts’ Governor’s Committee on Physical Fitness and Sports and is the President of The Sensible Nutrition Connection, Inc. (www.sensiblenutrition.com).
Showing posts with label diet. Show all posts
Showing posts with label diet. Show all posts
Friday, May 11, 2007
Nutrition for Traveling Athletes
Nutrition for Traveling Athletes.
By The Department of Sports Nutrition. Australian Institute of Sport.
From www.ais.org.au/nutrition
Travelling away from home for training and competition is standard practice for most elite and recreational athletes. Unfortunately, the disruptions and distractions of a new environment, changes in schedule and exposure to different foods can significantly affect usual eating habits. Major nutritional challenges faced by athletes while traveling include:
-achieving carbohydrate and protein requirements
-meeting daily vitamin and mineral requirements
-balancing energy intake
-maintaining adequate hydration
-food safety
It is essential that strategies are put in place to minimise the impact of travel on an athlete's food intake. Whether an athlete is travelling overseas or on a long local bus trip, the key to successful eating while on the move is planning and preparation.
Plan Ahead
A general plan consisting of where, when and what the athlete is planning to eat on each day should be constructed around the anticipated daily schedule. It is important to keep foods and meal times as similar as possible to the usual daily routine at home.
Research the Destination
Food patterns at the destination should be investigated as thoroughly as possible before leaving home:
-Are all important foods available?
-Is the accommodation self-catering or will it be necessary to rely on restaurants or takeaways?
-What are the hygiene and food safety risks?
The internet, travel agencies, embassies, competition organisers or other athletes who have travelled to the destination before can be used to gain information.
Choose Your Catering Style
Self Catering
Cooking skills, budget and access to shops will determine the meals that can be served. The availability of food at local shops, the cooking and storage facilities and available utensils need to be investigated before leaving home. Ideally, the menu should be planned in advance. Cookbooks such as the AIS Survival for the Fittest and Survival from the Fittest can be used as a guide. These books contain special menus for 1-7 days and the corresponding required ingredients. Useful items to pack when self catering include a can opener, chopping knife, extra utensils and storage containers for leftovers. For some locations, power cord adaptors, an in-cup heater and an electric kettle may also be useful.
Restaurant Eating
Athletes often stay in hotels where all meals are provided in the hotel restaurant. On other occasions, athletes or teams may choose to cater for their own breakfasts and lunch and use a restaurant for the evening meal. Where possible, restaurants should be investigated before leaving home. The meal options, cooking styles, opening hours and hygiene of the establishment should be considered. It is useful to book restaurants ahead of time as many businesses are unable to cater for specific requests or large groups at short notice. Discussing the proposed menu with restaurant staff in advance
will minimise problems at mealtime. This is particularly important when athletes have special dietary needs (e.g. vegetarian, food intolerances).
Meals that focus on carbohydrate choices such as rice, noodles and pasta are a good place to start. Add lean sources of protein such as lean meat, fish, chicken, beans or tofu and include plenty of vegetables. Avoid dishes that are deep fried or battered. Buffet style eating can be a good option as it allows athletes a range of choices. It is quicker than waiting for individual meals to arrive and is cost effective. One of the pitfalls of buffet eating is that it is easy to over indulge. This can be avoided by planning meals in advance and leaving the buffet when full. If using the same restaurant for more than a few days, vary the menu from day to day rather than within a meal to avoid boredom. If possible, avoid being solely reliant on restaurant/fast food options. They can be time consuming, expensive and a nutritional challenge.
Snacks
Snacks are an important component of eating and recovery nutrition plans for most athletes, however access to quality snacks can be difficult when travelling. It pays to take a supply of portable, non-perishable snack foods that are unlikely to be available at the destination. It may be useful to send a package of supplies ahead to decrease baggage. Remember to check with customs/quarantine regarding foods that are restricted from crossing certain borders.
Useful Food Items To Take
-cereal bars
-breakfast cereal
-canned snack pack fruits
-dried fruit
-instant noodles
-jam, honey, peanut butter, Vegemite
-powdered sports drink
-powdered liquid meal supplements
-powdered milk
-concentrated fruit juice
-baked beans and spaghetti
Hotels usually only cater for 3 meals/day. Arrange for snacks such as yoghurt, fruit and cereal bars to be placed out at meals so that athletes can take them for snacks later in the day. Alternatively, arrange for a communal area to be stocked with snacks (i.e. the manager's room).
Travelling by Air
Meals and Snacks
Athletes are not used to forced inactivity therefore hours spent on a plane may lead to boredom. It is important that athletes avoid over eating to relieve boredom. Taking other activities on board, drinking water regularly and chewing sugar-free gum can decrease the temptation to snack excessively on long flights. Alternatively, athletes with high-energy needs may struggle to meet their needs if they rely solely on in-flight catering. This may cause the athlete to arrive at the competition destination with reduced fuel stores. Several strategies can be taken to minimise these risks to performance:
Find out if special meals (e.g. sports, low-fat, vegetarian) are available on the flight.
Enquire about the in-flight menu and timing of the meal service in advance.
-On long flights, try to adopt a similar meal and sleep pattern to that anticipated at your destination. This may help to reduce the effects of jet lag.
-Athletes with reduced energy needs should pay particular attention to meals and snacks provided during the flight. It is not necessary to eat everything offered.
-It may be better to take your own snacks rather than be tempted by all the extra tid bits offered in flight.
-It is advisable to pack extra snacks in carry-on luggage. Food available for sale at airports tends to be expensive and it can be difficult to find nutritious options. It is always useful to have some supplies in case of unexpected delays.
In-Flight Fluid
The risk of becoming dehydrated on long flights is high as the pressurised cabins cause increased fluid losses from the skin and lungs. Symptoms of dehydration may include headaches or slight constipation. It is inadequate to rely on cabin service for fluid as the serve sizes of drinks is very small. Athletes should take their own supply of bottled water onto the flight to supplement the water, juice and soft drink provided in the air.
Sports drinks are also a useful choice as they provide a small amount of sodium that helps promote thirst (therefore encourages a greater fluid intake), and decreases urine losses. Aim to drink approximately 1 cup per hour during the flight. Caffeine-containing fluids such as tea, coffee and cola drinks may cause increased urine production, but can still contribute to a positive fluid balance in athletes (especially in those who regularly drink caffeinated drinks). Alcohol should be avoided on flights.
Food Safety at the Destination
Gastrointestinal problems are common when travelling to
foreign destinations. These can occur in both developing countries and 'safe' destinations. Adopting good personal hygiene and food safety practices will help to decrease the risk of infection and illness.
If the local water is unsafe to drink:
-Drink only bottled water or drinks from sealed containers.
-Avoid ice in drinks.
-Clean teeth with bottled water.
-Avoid salad vegetables unless washed in bottled or boiled water.
-Only eat fruit if it can be peeled.
In 'high risk' areas:
-Eat only from reputable hotels or well known franchises.
-Avoid street stalls and markets.
-Be wary of fish and shellfish.
-Only consume food that is steaming hot or has been refrigerated.
At all destinations:
-Avoid sharing cups, bottles or utensils as infections and illness can be transmitted this way.
If vomiting or diarrhoea does occur, it is important to replace lost fluids and electrolytes. Oral rehydration solutions and a safe water supply should be used. A bland diet consisting of dry toast, crackers, biscuits and rice may help. Avoid alcohol, fatty foods and dairy foods until the diarrhoea has ceased.
Food at the Competition Venue
Unfortunately, most sporting venues provide food choices such as deep fried snack foods, crisps and chocolate. Nutritious options are often hard to find. Athletes should carry pre and post exercise snacks and drinks to the venue to ensure that appropriate choices are readily available. Sandwiches, cereal bars, fruit, juice, liquid meal supplements and bottled or powdered sports drinks are ideal. Check that the venue has accessible water outlets and that the water is safe to drink. Carry your own bottled water if the water supply is in doubt.
Case Study
The following case study outlines the strategy an AIS sports dietitian used to assist a volleyball team survive an international trip. The team travelled to India for 3 weeks. It was the first overseas trip for many of the athletes.
Strategy 1: Assess Travel Itinerary and Competition Schedule
The team schedule, accommodation, dining options and goals were discussed with coaching staff.
Players were to train or compete daily. 3 meals per day were to be provided by hotel restaurants.
Coaching staff and senior players who had competed in India previously were consulted regarding anticipated food availability, quality, safety and potential problems.
Strategy 2: Identify Potential Nutrition Issues
-Possible avoidance of local food due to unfamiliarity and dislike of spicy food.
-Dehydration (high temperatures and humidity).
-Limited recovery time between sessions.
-Availability of recovery foods and fluids.
-Side effects of plane travel (first training session scheduled for the day of arrival).
-High risk of gastrointestinal disturbances.
Strategy 3: Education Prior to Travel
Activities were planned prior to travel to help avoid potential problems and to ensure appropriate nutritional strategies were followed.
-An Indian cooking night was organised for team members to increase awareness of Indian foods.
The team was educated on hydration strategies and hygiene issues. Bottled water was known to be readily available in India.
-The team was educated on issues regarding plane travel. Each athlete was provided with a small pack containing snacks, water and sports drink for use on the flight.
-The team was supplied with a range of portable foods to supplement the player's eating plans and cater for recovery needs. Useful utensils were also provided. Team provisions included:
-cereal bars
-cereal
-powdered milk
-instant noodles
-small tins of baked beans and spaghetti
-powdered liquid meal supplement
-powdered sports drink
-powdered oral rehydration solution
-electric kettle
-power adaptor plug
-can opener
Outcome
Players and coaches commented that the preparation and education prior to traveling was of great benefit. This was the first trip to India where no one became sick. This was attributed to the education players received prior to departure and the provision of safe snack choices. The athletes had confidence that they could adhere to good nutritional strategies while in a foreign environment. This helped the team perform to their full potential.
By The Department of Sports Nutrition. Australian Institute of Sport.
From www.ais.org.au/nutrition
Travelling away from home for training and competition is standard practice for most elite and recreational athletes. Unfortunately, the disruptions and distractions of a new environment, changes in schedule and exposure to different foods can significantly affect usual eating habits. Major nutritional challenges faced by athletes while traveling include:
-achieving carbohydrate and protein requirements
-meeting daily vitamin and mineral requirements
-balancing energy intake
-maintaining adequate hydration
-food safety
It is essential that strategies are put in place to minimise the impact of travel on an athlete's food intake. Whether an athlete is travelling overseas or on a long local bus trip, the key to successful eating while on the move is planning and preparation.
Plan Ahead
A general plan consisting of where, when and what the athlete is planning to eat on each day should be constructed around the anticipated daily schedule. It is important to keep foods and meal times as similar as possible to the usual daily routine at home.
Research the Destination
Food patterns at the destination should be investigated as thoroughly as possible before leaving home:
-Are all important foods available?
-Is the accommodation self-catering or will it be necessary to rely on restaurants or takeaways?
-What are the hygiene and food safety risks?
The internet, travel agencies, embassies, competition organisers or other athletes who have travelled to the destination before can be used to gain information.
Choose Your Catering Style
Self Catering
Cooking skills, budget and access to shops will determine the meals that can be served. The availability of food at local shops, the cooking and storage facilities and available utensils need to be investigated before leaving home. Ideally, the menu should be planned in advance. Cookbooks such as the AIS Survival for the Fittest and Survival from the Fittest can be used as a guide. These books contain special menus for 1-7 days and the corresponding required ingredients. Useful items to pack when self catering include a can opener, chopping knife, extra utensils and storage containers for leftovers. For some locations, power cord adaptors, an in-cup heater and an electric kettle may also be useful.
Restaurant Eating
Athletes often stay in hotels where all meals are provided in the hotel restaurant. On other occasions, athletes or teams may choose to cater for their own breakfasts and lunch and use a restaurant for the evening meal. Where possible, restaurants should be investigated before leaving home. The meal options, cooking styles, opening hours and hygiene of the establishment should be considered. It is useful to book restaurants ahead of time as many businesses are unable to cater for specific requests or large groups at short notice. Discussing the proposed menu with restaurant staff in advance
will minimise problems at mealtime. This is particularly important when athletes have special dietary needs (e.g. vegetarian, food intolerances).
Meals that focus on carbohydrate choices such as rice, noodles and pasta are a good place to start. Add lean sources of protein such as lean meat, fish, chicken, beans or tofu and include plenty of vegetables. Avoid dishes that are deep fried or battered. Buffet style eating can be a good option as it allows athletes a range of choices. It is quicker than waiting for individual meals to arrive and is cost effective. One of the pitfalls of buffet eating is that it is easy to over indulge. This can be avoided by planning meals in advance and leaving the buffet when full. If using the same restaurant for more than a few days, vary the menu from day to day rather than within a meal to avoid boredom. If possible, avoid being solely reliant on restaurant/fast food options. They can be time consuming, expensive and a nutritional challenge.
Snacks
Snacks are an important component of eating and recovery nutrition plans for most athletes, however access to quality snacks can be difficult when travelling. It pays to take a supply of portable, non-perishable snack foods that are unlikely to be available at the destination. It may be useful to send a package of supplies ahead to decrease baggage. Remember to check with customs/quarantine regarding foods that are restricted from crossing certain borders.
Useful Food Items To Take
-cereal bars
-breakfast cereal
-canned snack pack fruits
-dried fruit
-instant noodles
-jam, honey, peanut butter, Vegemite
-powdered sports drink
-powdered liquid meal supplements
-powdered milk
-concentrated fruit juice
-baked beans and spaghetti
Hotels usually only cater for 3 meals/day. Arrange for snacks such as yoghurt, fruit and cereal bars to be placed out at meals so that athletes can take them for snacks later in the day. Alternatively, arrange for a communal area to be stocked with snacks (i.e. the manager's room).
Travelling by Air
Meals and Snacks
Athletes are not used to forced inactivity therefore hours spent on a plane may lead to boredom. It is important that athletes avoid over eating to relieve boredom. Taking other activities on board, drinking water regularly and chewing sugar-free gum can decrease the temptation to snack excessively on long flights. Alternatively, athletes with high-energy needs may struggle to meet their needs if they rely solely on in-flight catering. This may cause the athlete to arrive at the competition destination with reduced fuel stores. Several strategies can be taken to minimise these risks to performance:
Find out if special meals (e.g. sports, low-fat, vegetarian) are available on the flight.
Enquire about the in-flight menu and timing of the meal service in advance.
-On long flights, try to adopt a similar meal and sleep pattern to that anticipated at your destination. This may help to reduce the effects of jet lag.
-Athletes with reduced energy needs should pay particular attention to meals and snacks provided during the flight. It is not necessary to eat everything offered.
-It may be better to take your own snacks rather than be tempted by all the extra tid bits offered in flight.
-It is advisable to pack extra snacks in carry-on luggage. Food available for sale at airports tends to be expensive and it can be difficult to find nutritious options. It is always useful to have some supplies in case of unexpected delays.
In-Flight Fluid
The risk of becoming dehydrated on long flights is high as the pressurised cabins cause increased fluid losses from the skin and lungs. Symptoms of dehydration may include headaches or slight constipation. It is inadequate to rely on cabin service for fluid as the serve sizes of drinks is very small. Athletes should take their own supply of bottled water onto the flight to supplement the water, juice and soft drink provided in the air.
Sports drinks are also a useful choice as they provide a small amount of sodium that helps promote thirst (therefore encourages a greater fluid intake), and decreases urine losses. Aim to drink approximately 1 cup per hour during the flight. Caffeine-containing fluids such as tea, coffee and cola drinks may cause increased urine production, but can still contribute to a positive fluid balance in athletes (especially in those who regularly drink caffeinated drinks). Alcohol should be avoided on flights.
Food Safety at the Destination
Gastrointestinal problems are common when travelling to
foreign destinations. These can occur in both developing countries and 'safe' destinations. Adopting good personal hygiene and food safety practices will help to decrease the risk of infection and illness.
If the local water is unsafe to drink:
-Drink only bottled water or drinks from sealed containers.
-Avoid ice in drinks.
-Clean teeth with bottled water.
-Avoid salad vegetables unless washed in bottled or boiled water.
-Only eat fruit if it can be peeled.
In 'high risk' areas:
-Eat only from reputable hotels or well known franchises.
-Avoid street stalls and markets.
-Be wary of fish and shellfish.
-Only consume food that is steaming hot or has been refrigerated.
At all destinations:
-Avoid sharing cups, bottles or utensils as infections and illness can be transmitted this way.
If vomiting or diarrhoea does occur, it is important to replace lost fluids and electrolytes. Oral rehydration solutions and a safe water supply should be used. A bland diet consisting of dry toast, crackers, biscuits and rice may help. Avoid alcohol, fatty foods and dairy foods until the diarrhoea has ceased.
Food at the Competition Venue
Unfortunately, most sporting venues provide food choices such as deep fried snack foods, crisps and chocolate. Nutritious options are often hard to find. Athletes should carry pre and post exercise snacks and drinks to the venue to ensure that appropriate choices are readily available. Sandwiches, cereal bars, fruit, juice, liquid meal supplements and bottled or powdered sports drinks are ideal. Check that the venue has accessible water outlets and that the water is safe to drink. Carry your own bottled water if the water supply is in doubt.
Case Study
The following case study outlines the strategy an AIS sports dietitian used to assist a volleyball team survive an international trip. The team travelled to India for 3 weeks. It was the first overseas trip for many of the athletes.
Strategy 1: Assess Travel Itinerary and Competition Schedule
The team schedule, accommodation, dining options and goals were discussed with coaching staff.
Players were to train or compete daily. 3 meals per day were to be provided by hotel restaurants.
Coaching staff and senior players who had competed in India previously were consulted regarding anticipated food availability, quality, safety and potential problems.
Strategy 2: Identify Potential Nutrition Issues
-Possible avoidance of local food due to unfamiliarity and dislike of spicy food.
-Dehydration (high temperatures and humidity).
-Limited recovery time between sessions.
-Availability of recovery foods and fluids.
-Side effects of plane travel (first training session scheduled for the day of arrival).
-High risk of gastrointestinal disturbances.
Strategy 3: Education Prior to Travel
Activities were planned prior to travel to help avoid potential problems and to ensure appropriate nutritional strategies were followed.
-An Indian cooking night was organised for team members to increase awareness of Indian foods.
The team was educated on hydration strategies and hygiene issues. Bottled water was known to be readily available in India.
-The team was educated on issues regarding plane travel. Each athlete was provided with a small pack containing snacks, water and sports drink for use on the flight.
-The team was supplied with a range of portable foods to supplement the player's eating plans and cater for recovery needs. Useful utensils were also provided. Team provisions included:
-cereal bars
-cereal
-powdered milk
-instant noodles
-small tins of baked beans and spaghetti
-powdered liquid meal supplement
-powdered sports drink
-powdered oral rehydration solution
-electric kettle
-power adaptor plug
-can opener
Outcome
Players and coaches commented that the preparation and education prior to traveling was of great benefit. This was the first trip to India where no one became sick. This was attributed to the education players received prior to departure and the provision of safe snack choices. The athletes had confidence that they could adhere to good nutritional strategies while in a foreign environment. This helped the team perform to their full potential.
Thursday, May 10, 2007
Fuel For Rowing
Fuel For Rowing
By The Department of Sports Nutrition AIS
-
Characteristics of the Sport
Rowing events are held over 2000 metres and typically take 5.5 to 7 minutes depending on the crew. Crews are distinguished by the number of members in the boat (singles, doubles, fours, eights), whether there is a coxswain steering, and whether the boat is sculled (two oars per person) or rowed (one oar each). Rowing involves lightweight and heavyweight competition. In the lightweight division, male athletes are not permitted to exceed 72.5kg with a crew average of 70kg. For females, the maximum individual weight is 59kg with a crew average of 57kg. Rowing places great demands on both the aerobic and anaerobic energy systems and requires great power and strength.
Training
Rowing requires a unique mix of technique, power and endurance of both the aerobic and anaerobic energy systems. This requires long hours of intense training even though events only last 5-7 minutes. Elite rowers train 8-10 months of the year. A typical rowing session covers 20 km with 1-2 sessions being held on the water each day. In addition, rowers undertake gym sessions 3-4 times per week to develop strength and muscular endurance. Some rowers may also include additional aerobic sessions such as cycling or running.
Competition
Regattas may last from two days to a week. Competitors must progress through heats and semi-finals to earn a berth in the finals. Competitors who fail to qualify for semifinals directly from the heats contest a repechage to earn a place in the semi-final. At the major regattas rowers will generally only contest one event per day with the regatta lasting roughly one week. In Club regattas rowers may race up to three times in one day. Light training is undertaken on any rest days. Lightweight rowers must weigh-in two hours prior to their event but do not have to weigh in again if they are racing in multiple events in one day.
Physical Characteristics
Heavyweight rowers are tall and heavy with strong muscles and long limbs. While muscle mass should account for a large proportion of body mass, absolute mass is important therefore body fat levels are often relatively high. Lightweight rowers aim to keep body fat levels low to maintain a good power-to-weight ratio.
Common Nutrition Issues
Training Nutrition
Rowers have very high energy and carbohydrate requirements to support training loads and meet body weight and strength goals. All rowers need to work hard to recover between training sessions. A high-energy, high-carbohydrate, nutrient-dense diet is required. Some rowers (particularly male heavyweights) struggle with the shear volume of food they need to consume. Frequent snacks and use of compact, energy dense foods or drinks such as juice, flavoured milk, jam, honey, bars and liquid meals are necessary to keep the volume of food manageable. Rowers need to pay particular attention to recovery after training and organise themselves to have high-carbohydrate snacks on hand immediately after training sessions are completed.
Matters of Physique
It is an advantage to be heavy and strong in heavyweight rowing. As body weight is supported in the boat, higher body fat levels are not as great a disadvantage as they are in other weight bearing sports. However, at times, it may be necessary for heavyweight rowers to trim their skinfolds. In lightweight rowing the need to maintain low body fat levels becomes more important. Rowers needing to reduce skinfolds must target excess kilojoules in the diet. In particular, excess fat, alcohol and sugary foods should be targeted and replaced with more nutrient-dense choices.
Iron Status
Rowers can be at risk of poor iron status. In particular, females and adolescent males can struggle to meet their iron needs. Regular checks of iron status are recommended. Rowers should include sources of iron such as lean red meat, chicken, fortified cereals, wholegrain cereals, legumes and green vegetables in the diet on a regular basis. Advice from a sports dietitian should be sought if low iron status develops.
Fluid Needs
Long training sessions on the water lead to significant sweat losses, particularly when undertaken twice a day. The table below shows sweat losses and fluid intakes recorded on AIS rowers in different environmental conditions. Despite having drink bottles available, athletes failed to consume enough fluid to keep up with their sweat losses, particularly in hot weather. Note, even in cold weather, considerable sweat losses were seen.
Rowers should establish their individual fluid losses by weighing before and after training sessions. Each kilogram of weight lost is the equivalent to 1 litre of fluid. Adding the weight of any fluid or food consumed during the session to the weight change over the session provides an estimate of total fluid loss for the workout. However, to fully rehydrate a rower usually has to consume 150% of the remaining fluid deficit, over the next few hours, to regain fluid balance. For example, if a rower finishes a session 2 kg lighter and consumes 0.5 litre during the session, total sweat loss over the session is approximately 2.5 litres. Once individual requirements are known, a plan can be developed to allow rowers to meet fluid requirements in subsequent sessions. However, now that a deficit of 2 litres has occurred, the rower will need to drink approximately 3 litres during the next hours to compensate for continued urine and sweat losses until fluid balance is regained.
The following tips will assist with hydration:
Drink with all meals and snacks before a training session. Consume 300-400ml of fluid in the hour before training commences to ensure you begin each session hydrated.
Take sufficient drink bottles to training. Keep some in the coach's boat for topups.
Take a few seconds every 15-20 minutes or between pieces for a drink break.
Alternatively, try using a drink container like a hydration-pack, which is worn on
the back, to avoid having to take your hands off the oar to drink.
Rehydrate fully after the session.
Sports drinks are the recommended fluid choice during rowing.
Lightweight rowers should not consider a lower weight at the end of a workout to be a good sign. Even though dehydration is an inevitable part of making weight for competition, it is unnecessary and counterproductive in the training setting. Aim to train as well as possible at all sessions by staying as well hydrated as possible.
Competition Nutrition
Rowers should go into each race with fluid and fuel stores topped up, and feeling comfortable after the last meal. With the regatta or competition lasting a number of days, the challenge is to recover between each day's sessions and to prepare for the next race. Generally a meal that provides carbohydrate should be consumed 2-3 hours before a race. Suitable foods include breakfast cereal, toast, muffins, sandwiches, yoghurt, fruit, pasta with tomato sauce and creamed rice. Some rowers need to take special care with pre-race eating - it can be very uncomfortable to race with a full stomach. Low bulk choices such as liquid meals and sports bars can be useful in these situations.
With much of the day tied up in preparation and the race itself, there is usually little opportunity for rowers to meet their usual high-energy intake. Consequently, some rowers find that they quickly lose weight over the course of a competition. Rowers need to organise themselves to have nutritious food supplies at their fingertips at all times. Take along a supply of cereal bars, liquid meal supplements, sports bars, fruit bars, dried fruit, sandwiches, yoghurt, juice etc. Commence your recovery as soon as possible after each race by consuming some of these snack foods. Don't neglect fluid needs. You can be dehydrated from your rowing efforts, making-weight practices, or just from sitting in the sun watching the competition. Carbohydrate-containing fluids such as sports drinks are useful for topping up both fluid and carbohydrate stores.
Case Study
Terry was living in a university college and rowing with the university coxed fours. A training load of ten water sessions and three weight sessions each week meant Terry's energy requirements were enormous. Terry was careful to eat a high-carbohydrate diet to refuel but was struggling to maintain weight and was becoming tired. A consult with a sports dietitian revealed Terry had a good knowledge of carbohydrate-based foods and was focusing on these at meals, however he simply wasn't eating enough. Terry was only eating three times a day because he was limited to dining hall opening hours. He was trying to consume huge meals but was finding he physically couldn't stomach all the food he required.
The solution for Terry was to improve his access to food and eat more frequently rather than trying to consume huge amounts of food in one sitting. A pattern of six or seven meals and snacks per day in addition to high-energy drinks was required. First Terry discussed his problems with the chef at the university dining hall. Terry negotiated for the chef to provide Terry with a supply of snack foods such as cereal bars, canned fruit, breakfast cereal and milk. Sometimes these were eaten straight off the water, as Terry travelled back to university. An immediate snack followed up by a more substantial meal an hour later was a practical approach that worked on many days. Terry also started ordering a takeaway lunch pack with sandwiches, buns and fruit. In all, this meant Terry had a regular supply of foods available for pre-training and recovery snacks. The chef also agreed to keep an evening meal waiting on nights when Terry finished training late.
Terry invested in a milkshake maker and bought a supply of liquid meal supplements and sports drinks. Using the sports drinks during training was an easy way to increase Terry's carbohydrate intake. He was also able to make milkshakes or fruit smoothies in his room at night or early mornings. With time, Terry was able to regain his lost weight. By varying his snacks and drinks he avoided becoming bored with his meals and was able to maintain his increased body weight.
By The Department of Sports Nutrition AIS
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Characteristics of the Sport
Rowing events are held over 2000 metres and typically take 5.5 to 7 minutes depending on the crew. Crews are distinguished by the number of members in the boat (singles, doubles, fours, eights), whether there is a coxswain steering, and whether the boat is sculled (two oars per person) or rowed (one oar each). Rowing involves lightweight and heavyweight competition. In the lightweight division, male athletes are not permitted to exceed 72.5kg with a crew average of 70kg. For females, the maximum individual weight is 59kg with a crew average of 57kg. Rowing places great demands on both the aerobic and anaerobic energy systems and requires great power and strength.
Training
Rowing requires a unique mix of technique, power and endurance of both the aerobic and anaerobic energy systems. This requires long hours of intense training even though events only last 5-7 minutes. Elite rowers train 8-10 months of the year. A typical rowing session covers 20 km with 1-2 sessions being held on the water each day. In addition, rowers undertake gym sessions 3-4 times per week to develop strength and muscular endurance. Some rowers may also include additional aerobic sessions such as cycling or running.
Competition
Regattas may last from two days to a week. Competitors must progress through heats and semi-finals to earn a berth in the finals. Competitors who fail to qualify for semifinals directly from the heats contest a repechage to earn a place in the semi-final. At the major regattas rowers will generally only contest one event per day with the regatta lasting roughly one week. In Club regattas rowers may race up to three times in one day. Light training is undertaken on any rest days. Lightweight rowers must weigh-in two hours prior to their event but do not have to weigh in again if they are racing in multiple events in one day.
Physical Characteristics
Heavyweight rowers are tall and heavy with strong muscles and long limbs. While muscle mass should account for a large proportion of body mass, absolute mass is important therefore body fat levels are often relatively high. Lightweight rowers aim to keep body fat levels low to maintain a good power-to-weight ratio.
Common Nutrition Issues
Training Nutrition
Rowers have very high energy and carbohydrate requirements to support training loads and meet body weight and strength goals. All rowers need to work hard to recover between training sessions. A high-energy, high-carbohydrate, nutrient-dense diet is required. Some rowers (particularly male heavyweights) struggle with the shear volume of food they need to consume. Frequent snacks and use of compact, energy dense foods or drinks such as juice, flavoured milk, jam, honey, bars and liquid meals are necessary to keep the volume of food manageable. Rowers need to pay particular attention to recovery after training and organise themselves to have high-carbohydrate snacks on hand immediately after training sessions are completed.
Matters of Physique
It is an advantage to be heavy and strong in heavyweight rowing. As body weight is supported in the boat, higher body fat levels are not as great a disadvantage as they are in other weight bearing sports. However, at times, it may be necessary for heavyweight rowers to trim their skinfolds. In lightweight rowing the need to maintain low body fat levels becomes more important. Rowers needing to reduce skinfolds must target excess kilojoules in the diet. In particular, excess fat, alcohol and sugary foods should be targeted and replaced with more nutrient-dense choices.
Iron Status
Rowers can be at risk of poor iron status. In particular, females and adolescent males can struggle to meet their iron needs. Regular checks of iron status are recommended. Rowers should include sources of iron such as lean red meat, chicken, fortified cereals, wholegrain cereals, legumes and green vegetables in the diet on a regular basis. Advice from a sports dietitian should be sought if low iron status develops.
Fluid Needs
Long training sessions on the water lead to significant sweat losses, particularly when undertaken twice a day. The table below shows sweat losses and fluid intakes recorded on AIS rowers in different environmental conditions. Despite having drink bottles available, athletes failed to consume enough fluid to keep up with their sweat losses, particularly in hot weather. Note, even in cold weather, considerable sweat losses were seen.
Rowers should establish their individual fluid losses by weighing before and after training sessions. Each kilogram of weight lost is the equivalent to 1 litre of fluid. Adding the weight of any fluid or food consumed during the session to the weight change over the session provides an estimate of total fluid loss for the workout. However, to fully rehydrate a rower usually has to consume 150% of the remaining fluid deficit, over the next few hours, to regain fluid balance. For example, if a rower finishes a session 2 kg lighter and consumes 0.5 litre during the session, total sweat loss over the session is approximately 2.5 litres. Once individual requirements are known, a plan can be developed to allow rowers to meet fluid requirements in subsequent sessions. However, now that a deficit of 2 litres has occurred, the rower will need to drink approximately 3 litres during the next hours to compensate for continued urine and sweat losses until fluid balance is regained.
The following tips will assist with hydration:
Drink with all meals and snacks before a training session. Consume 300-400ml of fluid in the hour before training commences to ensure you begin each session hydrated.
Take sufficient drink bottles to training. Keep some in the coach's boat for topups.
Take a few seconds every 15-20 minutes or between pieces for a drink break.
Alternatively, try using a drink container like a hydration-pack, which is worn on
the back, to avoid having to take your hands off the oar to drink.
Rehydrate fully after the session.
Sports drinks are the recommended fluid choice during rowing.
Lightweight rowers should not consider a lower weight at the end of a workout to be a good sign. Even though dehydration is an inevitable part of making weight for competition, it is unnecessary and counterproductive in the training setting. Aim to train as well as possible at all sessions by staying as well hydrated as possible.
Competition Nutrition
Rowers should go into each race with fluid and fuel stores topped up, and feeling comfortable after the last meal. With the regatta or competition lasting a number of days, the challenge is to recover between each day's sessions and to prepare for the next race. Generally a meal that provides carbohydrate should be consumed 2-3 hours before a race. Suitable foods include breakfast cereal, toast, muffins, sandwiches, yoghurt, fruit, pasta with tomato sauce and creamed rice. Some rowers need to take special care with pre-race eating - it can be very uncomfortable to race with a full stomach. Low bulk choices such as liquid meals and sports bars can be useful in these situations.
With much of the day tied up in preparation and the race itself, there is usually little opportunity for rowers to meet their usual high-energy intake. Consequently, some rowers find that they quickly lose weight over the course of a competition. Rowers need to organise themselves to have nutritious food supplies at their fingertips at all times. Take along a supply of cereal bars, liquid meal supplements, sports bars, fruit bars, dried fruit, sandwiches, yoghurt, juice etc. Commence your recovery as soon as possible after each race by consuming some of these snack foods. Don't neglect fluid needs. You can be dehydrated from your rowing efforts, making-weight practices, or just from sitting in the sun watching the competition. Carbohydrate-containing fluids such as sports drinks are useful for topping up both fluid and carbohydrate stores.
Case Study
Terry was living in a university college and rowing with the university coxed fours. A training load of ten water sessions and three weight sessions each week meant Terry's energy requirements were enormous. Terry was careful to eat a high-carbohydrate diet to refuel but was struggling to maintain weight and was becoming tired. A consult with a sports dietitian revealed Terry had a good knowledge of carbohydrate-based foods and was focusing on these at meals, however he simply wasn't eating enough. Terry was only eating three times a day because he was limited to dining hall opening hours. He was trying to consume huge meals but was finding he physically couldn't stomach all the food he required.
The solution for Terry was to improve his access to food and eat more frequently rather than trying to consume huge amounts of food in one sitting. A pattern of six or seven meals and snacks per day in addition to high-energy drinks was required. First Terry discussed his problems with the chef at the university dining hall. Terry negotiated for the chef to provide Terry with a supply of snack foods such as cereal bars, canned fruit, breakfast cereal and milk. Sometimes these were eaten straight off the water, as Terry travelled back to university. An immediate snack followed up by a more substantial meal an hour later was a practical approach that worked on many days. Terry also started ordering a takeaway lunch pack with sandwiches, buns and fruit. In all, this meant Terry had a regular supply of foods available for pre-training and recovery snacks. The chef also agreed to keep an evening meal waiting on nights when Terry finished training late.
Terry invested in a milkshake maker and bought a supply of liquid meal supplements and sports drinks. Using the sports drinks during training was an easy way to increase Terry's carbohydrate intake. He was also able to make milkshakes or fruit smoothies in his room at night or early mornings. With time, Terry was able to regain his lost weight. By varying his snacks and drinks he avoided becoming bored with his meals and was able to maintain his increased body weight.
Energy Drinks, Sport Bars & Gels
Nutrition – Energy Drinks, Sport Bars & Gels
by Charlene Boudreau,
From USA Swimming
-
The use and selection of energy bars, sports drinks and gels has grown considerably over the past few years. For athletes, reasons for using these products are typically based on their convenience and potential performance-improving effects. Bars, drinks and gels provide a quick and easy means of supplying the body with calories and micronutrients (vitamins and minerals) when conventional foods are not available or feasible. Since swimmers typically workout and/or race in the morning when they may choose not to eat, and an overnight fast would force them to perform in a partially glycogen-depleted state, bars, drinks and gels may provide a compact, more tolerable “meal” substitution. In some cases, the addition of certain ingredients promises results.
Energy bars fall into 3 main categories, depending on their nutrient composition:
-High Carbohydrate Bars (>30 g carbohydrate)
-High Protein Bars (>12 g protein)
-Mixed Bars (usually >20 g carbohydrate, >10 g protein, 2.5-10 g fat).
High carbohydrate bars provide the fuel needed for tough endurance workouts. High protein bars are often promoted for post-workout recovery. Mixed bars make a healthy snack during the day when time is short and hunger is big.
Gels are typically high in carbohydrate (>30g) and low in fat (<1g) and protein (<12 g). They include mainly simple sugars, as opposed to complex carbohydrates. Since simple sugars reach the bloodstream faster than complex carbohydrates, which take longer to digest and be absorbed, gels are typically used in situations when carbohydrates are needed quickly. For swimmers, breaks between sets present an opportunity to provide the body with the energy (carbohydrate) it needs for long workouts.
Sports drinks have traditionally been comprised of carbohydrate and electrolytes in amounts that enhance fluid absorption and minimize gastrointestinal distress. Over the past 5 years, sports drinks have expanded to include those with added amino acids, herbal ingredients and herbal mental “boosters.” Many products have been marketed to a consumer base that goes beyond the competitive athlete and into the realm of the recreational and leisure activity participants.
In addition to the convenience factor, many energy bars, sports drinks and gels have direct scientifically proven benefits both during and following exercise. The two basic reasons why researchers suggest that athletes turn to these types of fuels are:
Fluid replenishment (drinks).
Energy provision (bars, drinks, gels).
Maintaining Hydration During Exercise - The daily sweat loss for elite level athletes can range from 1 to 1.5 liters per hour. Depending on the intensity and duration of the workouts, the daily water requirement for these athletes ranges from two to six liters per day. In extreme cases, this requirement may be as high as 16 liters per day if the climate is hot. Failure to maintain a hydrated state can lead to detrimental changes in the cardiovascular response to exercise, over-heating of the body and decreases in both maximal power and work capacity. Just a 2% drop in body weight due to dehydration can have an overall negative impact on exercise performance.
The collection of research addressing sports drinks is extensive and has evolved quite dramatically over the years. Studies have indicated that the ingestion of a 6-8% carbohydrate beverage (ex. Gatorade, Powerade) during prolonged strenuous exercise can delay fatigue and improve performance. The theory is that the carbohydrate drink provides sugar (glucose) to the blood, which spares glycogen (the body’s internal reserve of carbohydrate) during prolonged exercise. And we know that how well a fluid (sports drink or water) works depends on (1) how much is ingested (fluid ingestion), (2) how long it takes for that fluid to move from the stomach to the intestine (gastric emptying…the faster the better), (3) how long it takes to be absorbed from the intestine into the bloodstream (intestinal absorption) and (4) whether it weakens or enhances the body’s utilization of carbohydrate as a fuel (fuel utilization).
Providing Energy During Exercise - In addition to staying hydrated, athletes are faced with the task of fueling their bodies for performance. For activities lasting less than one hour, this can usually be accomplished with the pre-exercise meal or snack.
For longer-duration activities, this usually means “eating on the run.” Given the environment, swimmers face the added obstacle of the water. Conventional “dry” foods are not feasible, making products such as water, sports drinks, energy bars and gels their only options. This also leads to the questions of what, when, why and how much?
The use of bars, drinks and gels as fuel sources during exercise is based on their typically high carbohydrate content. Providing the body with carbohydrate during prolonged activity maintains blood sugar levels. The availability of this “fuel” during exercise allows the body to spare glycogen and can prolong the time an athlete can exercise before tiring. The well-researched sports drink (also called carbohydrate electrolyte drink) has traditionally been recommended for endurance events lasting
more than 90 minutes. However, recent research suggests that sports drinks can improve high intensity and sprint-interval sessions lasting less than an hour. This suggests a benefit to using sports drinks for fuel during workouts to a broader segment of the athletic community, including sprinters.
Hydrating the Body at Rest – Quality workouts depend on replenishing fuel stores that were spent during previous sessions. This includes, but is not limited to, fluids. Failure to correct a fluid deficit incurred from one workout before the next workout puts the athlete at risk for a compromised performance. Starting a session in a dehydrated state may cause a faster rise in core body temperature, greater cardiovascular strain and an impaired ability to dissipate heat. These effects may be exaggerated if the workout takes place in a hot environment. Therefore, re-hydrating and maintaining a hydrated state outside of practice times is just as critical to the athlete as hydrating during workouts.
Be aware that thirst is not always an accurate indicator of when an athlete should begin hydrating. For most athletes, by the time they are thirsty, they are already dehydrated. This makes the intake of fluids, including sports drinks, an important part of the daily nutrition program, especially during the recovery phase. It has been suggested that fluids containing sodium are more efficient at hydrating than plain water alone. According to the American College of Sports Medicine, “one should consume adequate fluids during the 24-hour period before an event and drink about 500 ml (about 17 oz) of fluid about 2 hours before exercise to promote adequate hydration and allow time for excretion of excess ingested water.”
Fueling the Body at Rest – As mentioned previously, quality workouts depend on replenishing fuel stores spent during previous sessions. Depending on the extent of depletion, it can take as long as 24 hours to fully replenish glycogen stores, but the first two hours post-workout are the most critical. Given the right fuel, glycogen synthesis during this time can occur as much as 2-3 times faster than normal (i.e. compared to if they were given no fuel at all). This is due to the increased sensitivity of muscle cells to the hormone insulin. It is well known that the ingestion of carbohydrate causes an insulin response (i.e. increasing glucose in blood increases insulin in the blood). The presence of insulin in the bloodstream promotes the uptake of glucose by the muscles. Once moved from blood to muscle, this glucose can then be converted to glycogen for storage. Certain proteins and amino acids have been shown to elicit an insulin response. When ingested with carbohydrate, they can create a “synergistic” effect. In other words, their combined effect is greater than the sum of their individual effects. Those found to have the greatest impact on insulin levels include protein hydrolysate mixtures, leucine, phenylalanine, and arginine.
In addition, insulin itself has been proposed as an important factor in muscle protein balance by increasing synthesis and decreasing degradation. Some researchers believe that when exercise acts as the stimulus and levels of circulating amino acids are high, a more anabolic (muscle-building) state is created. Unfortunately, research in this area is still limited, and questions still remain regarding how nutrition impacts resistance and intermittent activities. The general idea is to take advantage of the body’s natural post-exercise sensitivity to insulin by providing it with food that will (1) raise insulin levels, (2) put glucose in the bloodstream quickly and (3) enhance the conversion of glucose to glycogen.
At rest, such as during the pre- and post-workout periods, the use of energy bars, drinks and gels varies with personal preference, time available to eat, etc. In addition, athletes are compelled to select these products based on claims made by the manufacturers about the addition of various ingredients and which products are “the best.” Some of these claims are related to fat burning capabilities, the roles of electrolytes (sodium, potassium, chloride) and caffeine, and the addition of various carbohydrate/protein hydrolysate combinations. An important point to remember is that because most bars, drinks and gels are considered dietary supplements, they are subject to the less stringent regulation demonstrated within the supplement industry since the passing of the Dietary Supplements Health and Education Act of 1994
For this reason, it is worth the time for athletes and coaches to choose their bars, drinks and gels cautiously.
To address some of the issues mentioned above, I recently reviewed a collection of studies (Oliver & Tremblay, 2002; Kolkhorst, MacTaggart & Hansen, 1998; Haff, Kock, Potteiger, Kuphal, Magee, Green & Jakicic, 2000; Nassis, Williams & Chisnall, 1998; Brouns, Kovacs & Senden, 1998; Van Nieuwenhoven, Brummer & Brouns, 2000; Van Loon, Saris, Kruijshoop & Wagenmakers, 2000). The applications of this research are summarized below:
-Fifteen minutes may not be enough time to reap the benefits of ingesting carbohydrate prior to a workout.
-The claims made by the manufacturers of Sports Nutrition Bars are not always supported by science. An athlete may be better advised to choose a product that has KNOWN scientific benefits.
-Consuming Gatorlode or Gatorade before and during a workout may not enhance the amount lifted, force produced, or time to fatigue, but it can prevent muscle glycogen stores from declining.
-Maintaining this fuel source can have direct implications on a pool workout that closely follows a dryland/lifting session or vice versa. It allows the swimmers to come to workout with more “gas in the tank.”
-There has been some debate on the extent (if any) to which caffeine intake enhances endurance performance. Regardless of the controversy, many manufacturers of sports drinks, energy bars and gels have taken the initiative to add caffeine to their lists of ingredients.
-When given the choice, many athletes will drink more of a sports drink than water because they prefer the taste.
-The inclusion of caffeine in sports drinks may not affect gastrointestinal variables, but using a drink like Coca Cola to rehydrate the body after a tough workout may have an adverse effect on electrolyte balance.
-Since caffeine appears to increase magnesium and calcium loss in urine, rehydration should be accomplished with 6-8% carbohydrate-electrolyte sports drinks that are caffeine-free, rather than any drinks that contain caffeine and/or do not include electrolytes.
-The enhanced insulin response caused by the addition of protein to the carbohydrate-only drink can be achieved just as effectively by adding the same amount of extra carbohydrate.
-Consuming carbohydrate in the amount of 0.8 g/kg/hr (58 grams/hr for a 160 lb male) is not as effective in replenishing glycogen as consuming 1.2 g/kg/hr (87 grams/hr for a 160 lb male). In other words, 0.8 g/kg/hr (32 fl oz of Gatorade for a 160 lb male) is not enough to maximize the repletion process.
The Final Word
When it comes to choosing an energy bar, sports drink or gel, the most important things to know are: what is in it and how does it work? To help guide your athletes in their selection and use of bars, drinks and gels, offer these tips:
-Check for Effective Ingredients in Drinks. The post-exercise rehydration drink should contain Carbohydrate (30-80 g/L), Sodium (400-1000 mg/L), and Potassium, Chloride in small quantities. If a drink does not contain these ingredients, it may not be effective in providing energy and maintaining hydration.
-Drink Water with Bars. Drink at least 8-16oz (about 1 water bottle full) of water along with every energy bar you eat. For each packet of gel, take about 4oz of water. This helps keep your body hydrated while helping with the digestion of the product and the absorption of its contents.
-Experiment. Swimmers will differ in their preferences when it comes to flavor, texture, palatability (feel of food in the mouth) and digestive tolerance. Test energy bars and gels in real life settings. Avoid mixed bars immediately before and during workout, as the higher fat content may slow digestion and/or upset your stomach. The same applies for bars that are high in fiber, >5 g. Do not wait until meet day to take your first bite. In doing this, you risk experiencing adverse effects, which could include, among other possible side affects, nausea, cramping, and unanticipated bathroom visits!
-Beware of Extra “Stuff.” Many manufacturers claim that the extra vitamins and minerals they have conveniently added to their product are critical for the energy boost. The fact is that the energy a swimmer gets from a sports bar or gel comes from the calories it provides. While the importance of vitamins and minerals for proper body functioning cannot be denied, adequate amounts of these nutrients can be obtained by consuming a variety of foods from all of the foods groups on a daily basis. In addition, many of the “extra” ingredients supplied in these products may not be ones a competitive athlete wants or needs to ingest. Be extra cautious of herbal ingredients.
-Read the Ingredients. This tip is simple, but it is extremely important! You must be aware of what you are eating. Pay particular attention to the ingredients list on every individual package, and avoid products that may contain substances that you know or even think may appear on the prohibited substance list. Sometimes fortified products contain even more than what actually appears on the list. It is possible. It does happen. It is your responsibility.
-Eat “Real Food.” While bars, drinks and gels provide a convenient way to get the extra calories necessary to keep pace with the swimmer’s lifestyle, it is critical to eat a variety of foods from all of the food groups every day. Use energy bars and gels only to compliment a well-balanced diet when energy demands are high and “real food” is not an option.
For additional information on issues related to this review, visit the following web links:
-Laboratory Evaluation of Nutrition Bars:
http://www.consumerlab.com/results/nutbars.asp
-Laboratory Evaluation of Powders and Drinks:
http://www.consumerlab.com/results/nutdrinks.asp
Recommended Reading
-American College of Sports Medicine. (1996). American College of Sports Medicine position stand: Exercise and fluid replacement. Medicine and Science in Sports Medicine 28(1):i-vii.
-Coombes, J.S. and K.L. Hamilton. (2000). The effectiveness of commercially available sports drinks. Sports Medicine 29(3):181-209.
-Cunningham, J.J. (1997). Is potassium needed in sports drinks for fluid replacement during exercise? International Journal of Sport Nutrition 7:154-159.
-Gleeson, M. and N.C. Bishop. (2000). Modification of immune responses to exercise by carbohydrate, glutamine and anti-oxidant supplements. Immunology and Cell Biology 78:554-561.
-Green, G.A., D. H. Catlin and B. Starcevic. (2001). Analysis of over-the-counter dietary supplements. Clinical Journal of Sport Medicine 11:254-259.
-Harvard University. (2000). Power in a bar or procey snack? Harvard Women’s Health Watch July:6.
-Leiper, J.B. (1998). Intestinal water absorption – implications for the formulation of rehydration solutions. International Journal of Sports Medicine 19:S129-S132.
-Maughan, R.J. (1998). The sports drink as a functional food: formulations for successful performance. Proceedings of the Nutrition Society 57:15-23.
-Murray, R. (1998). Rehydration strategies – balancing substrate, fluid, and electrolyte provision. International Journal of Sports Medicine 19:S133-S135.
-Ryan, M. (1997). Sports drinks: research asks for reevaluation of current recommendations. Journal of the American Dietetics Association 97(suppl):S197- S198.
-Tufts University. (2001). Why most energy bars should not go home with most people. Tufts University Health and Nutrition Letter 19(5):6.
by Charlene Boudreau,
From USA Swimming
-
The use and selection of energy bars, sports drinks and gels has grown considerably over the past few years. For athletes, reasons for using these products are typically based on their convenience and potential performance-improving effects. Bars, drinks and gels provide a quick and easy means of supplying the body with calories and micronutrients (vitamins and minerals) when conventional foods are not available or feasible. Since swimmers typically workout and/or race in the morning when they may choose not to eat, and an overnight fast would force them to perform in a partially glycogen-depleted state, bars, drinks and gels may provide a compact, more tolerable “meal” substitution. In some cases, the addition of certain ingredients promises results.
Energy bars fall into 3 main categories, depending on their nutrient composition:
-High Carbohydrate Bars (>30 g carbohydrate)
-High Protein Bars (>12 g protein)
-Mixed Bars (usually >20 g carbohydrate, >10 g protein, 2.5-10 g fat).
High carbohydrate bars provide the fuel needed for tough endurance workouts. High protein bars are often promoted for post-workout recovery. Mixed bars make a healthy snack during the day when time is short and hunger is big.
Gels are typically high in carbohydrate (>30g) and low in fat (<1g) and protein (<12 g). They include mainly simple sugars, as opposed to complex carbohydrates. Since simple sugars reach the bloodstream faster than complex carbohydrates, which take longer to digest and be absorbed, gels are typically used in situations when carbohydrates are needed quickly. For swimmers, breaks between sets present an opportunity to provide the body with the energy (carbohydrate) it needs for long workouts.
Sports drinks have traditionally been comprised of carbohydrate and electrolytes in amounts that enhance fluid absorption and minimize gastrointestinal distress. Over the past 5 years, sports drinks have expanded to include those with added amino acids, herbal ingredients and herbal mental “boosters.” Many products have been marketed to a consumer base that goes beyond the competitive athlete and into the realm of the recreational and leisure activity participants.
In addition to the convenience factor, many energy bars, sports drinks and gels have direct scientifically proven benefits both during and following exercise. The two basic reasons why researchers suggest that athletes turn to these types of fuels are:
Fluid replenishment (drinks).
Energy provision (bars, drinks, gels).
Maintaining Hydration During Exercise - The daily sweat loss for elite level athletes can range from 1 to 1.5 liters per hour. Depending on the intensity and duration of the workouts, the daily water requirement for these athletes ranges from two to six liters per day. In extreme cases, this requirement may be as high as 16 liters per day if the climate is hot. Failure to maintain a hydrated state can lead to detrimental changes in the cardiovascular response to exercise, over-heating of the body and decreases in both maximal power and work capacity. Just a 2% drop in body weight due to dehydration can have an overall negative impact on exercise performance.
The collection of research addressing sports drinks is extensive and has evolved quite dramatically over the years. Studies have indicated that the ingestion of a 6-8% carbohydrate beverage (ex. Gatorade, Powerade) during prolonged strenuous exercise can delay fatigue and improve performance. The theory is that the carbohydrate drink provides sugar (glucose) to the blood, which spares glycogen (the body’s internal reserve of carbohydrate) during prolonged exercise. And we know that how well a fluid (sports drink or water) works depends on (1) how much is ingested (fluid ingestion), (2) how long it takes for that fluid to move from the stomach to the intestine (gastric emptying…the faster the better), (3) how long it takes to be absorbed from the intestine into the bloodstream (intestinal absorption) and (4) whether it weakens or enhances the body’s utilization of carbohydrate as a fuel (fuel utilization).
Providing Energy During Exercise - In addition to staying hydrated, athletes are faced with the task of fueling their bodies for performance. For activities lasting less than one hour, this can usually be accomplished with the pre-exercise meal or snack.
For longer-duration activities, this usually means “eating on the run.” Given the environment, swimmers face the added obstacle of the water. Conventional “dry” foods are not feasible, making products such as water, sports drinks, energy bars and gels their only options. This also leads to the questions of what, when, why and how much?
The use of bars, drinks and gels as fuel sources during exercise is based on their typically high carbohydrate content. Providing the body with carbohydrate during prolonged activity maintains blood sugar levels. The availability of this “fuel” during exercise allows the body to spare glycogen and can prolong the time an athlete can exercise before tiring. The well-researched sports drink (also called carbohydrate electrolyte drink) has traditionally been recommended for endurance events lasting
more than 90 minutes. However, recent research suggests that sports drinks can improve high intensity and sprint-interval sessions lasting less than an hour. This suggests a benefit to using sports drinks for fuel during workouts to a broader segment of the athletic community, including sprinters.
Hydrating the Body at Rest – Quality workouts depend on replenishing fuel stores that were spent during previous sessions. This includes, but is not limited to, fluids. Failure to correct a fluid deficit incurred from one workout before the next workout puts the athlete at risk for a compromised performance. Starting a session in a dehydrated state may cause a faster rise in core body temperature, greater cardiovascular strain and an impaired ability to dissipate heat. These effects may be exaggerated if the workout takes place in a hot environment. Therefore, re-hydrating and maintaining a hydrated state outside of practice times is just as critical to the athlete as hydrating during workouts.
Be aware that thirst is not always an accurate indicator of when an athlete should begin hydrating. For most athletes, by the time they are thirsty, they are already dehydrated. This makes the intake of fluids, including sports drinks, an important part of the daily nutrition program, especially during the recovery phase. It has been suggested that fluids containing sodium are more efficient at hydrating than plain water alone. According to the American College of Sports Medicine, “one should consume adequate fluids during the 24-hour period before an event and drink about 500 ml (about 17 oz) of fluid about 2 hours before exercise to promote adequate hydration and allow time for excretion of excess ingested water.”
Fueling the Body at Rest – As mentioned previously, quality workouts depend on replenishing fuel stores spent during previous sessions. Depending on the extent of depletion, it can take as long as 24 hours to fully replenish glycogen stores, but the first two hours post-workout are the most critical. Given the right fuel, glycogen synthesis during this time can occur as much as 2-3 times faster than normal (i.e. compared to if they were given no fuel at all). This is due to the increased sensitivity of muscle cells to the hormone insulin. It is well known that the ingestion of carbohydrate causes an insulin response (i.e. increasing glucose in blood increases insulin in the blood). The presence of insulin in the bloodstream promotes the uptake of glucose by the muscles. Once moved from blood to muscle, this glucose can then be converted to glycogen for storage. Certain proteins and amino acids have been shown to elicit an insulin response. When ingested with carbohydrate, they can create a “synergistic” effect. In other words, their combined effect is greater than the sum of their individual effects. Those found to have the greatest impact on insulin levels include protein hydrolysate mixtures, leucine, phenylalanine, and arginine.
In addition, insulin itself has been proposed as an important factor in muscle protein balance by increasing synthesis and decreasing degradation. Some researchers believe that when exercise acts as the stimulus and levels of circulating amino acids are high, a more anabolic (muscle-building) state is created. Unfortunately, research in this area is still limited, and questions still remain regarding how nutrition impacts resistance and intermittent activities. The general idea is to take advantage of the body’s natural post-exercise sensitivity to insulin by providing it with food that will (1) raise insulin levels, (2) put glucose in the bloodstream quickly and (3) enhance the conversion of glucose to glycogen.
At rest, such as during the pre- and post-workout periods, the use of energy bars, drinks and gels varies with personal preference, time available to eat, etc. In addition, athletes are compelled to select these products based on claims made by the manufacturers about the addition of various ingredients and which products are “the best.” Some of these claims are related to fat burning capabilities, the roles of electrolytes (sodium, potassium, chloride) and caffeine, and the addition of various carbohydrate/protein hydrolysate combinations. An important point to remember is that because most bars, drinks and gels are considered dietary supplements, they are subject to the less stringent regulation demonstrated within the supplement industry since the passing of the Dietary Supplements Health and Education Act of 1994
For this reason, it is worth the time for athletes and coaches to choose their bars, drinks and gels cautiously.
To address some of the issues mentioned above, I recently reviewed a collection of studies (Oliver & Tremblay, 2002; Kolkhorst, MacTaggart & Hansen, 1998; Haff, Kock, Potteiger, Kuphal, Magee, Green & Jakicic, 2000; Nassis, Williams & Chisnall, 1998; Brouns, Kovacs & Senden, 1998; Van Nieuwenhoven, Brummer & Brouns, 2000; Van Loon, Saris, Kruijshoop & Wagenmakers, 2000). The applications of this research are summarized below:
-Fifteen minutes may not be enough time to reap the benefits of ingesting carbohydrate prior to a workout.
-The claims made by the manufacturers of Sports Nutrition Bars are not always supported by science. An athlete may be better advised to choose a product that has KNOWN scientific benefits.
-Consuming Gatorlode or Gatorade before and during a workout may not enhance the amount lifted, force produced, or time to fatigue, but it can prevent muscle glycogen stores from declining.
-Maintaining this fuel source can have direct implications on a pool workout that closely follows a dryland/lifting session or vice versa. It allows the swimmers to come to workout with more “gas in the tank.”
-There has been some debate on the extent (if any) to which caffeine intake enhances endurance performance. Regardless of the controversy, many manufacturers of sports drinks, energy bars and gels have taken the initiative to add caffeine to their lists of ingredients.
-When given the choice, many athletes will drink more of a sports drink than water because they prefer the taste.
-The inclusion of caffeine in sports drinks may not affect gastrointestinal variables, but using a drink like Coca Cola to rehydrate the body after a tough workout may have an adverse effect on electrolyte balance.
-Since caffeine appears to increase magnesium and calcium loss in urine, rehydration should be accomplished with 6-8% carbohydrate-electrolyte sports drinks that are caffeine-free, rather than any drinks that contain caffeine and/or do not include electrolytes.
-The enhanced insulin response caused by the addition of protein to the carbohydrate-only drink can be achieved just as effectively by adding the same amount of extra carbohydrate.
-Consuming carbohydrate in the amount of 0.8 g/kg/hr (58 grams/hr for a 160 lb male) is not as effective in replenishing glycogen as consuming 1.2 g/kg/hr (87 grams/hr for a 160 lb male). In other words, 0.8 g/kg/hr (32 fl oz of Gatorade for a 160 lb male) is not enough to maximize the repletion process.
The Final Word
When it comes to choosing an energy bar, sports drink or gel, the most important things to know are: what is in it and how does it work? To help guide your athletes in their selection and use of bars, drinks and gels, offer these tips:
-Check for Effective Ingredients in Drinks. The post-exercise rehydration drink should contain Carbohydrate (30-80 g/L), Sodium (400-1000 mg/L), and Potassium, Chloride in small quantities. If a drink does not contain these ingredients, it may not be effective in providing energy and maintaining hydration.
-Drink Water with Bars. Drink at least 8-16oz (about 1 water bottle full) of water along with every energy bar you eat. For each packet of gel, take about 4oz of water. This helps keep your body hydrated while helping with the digestion of the product and the absorption of its contents.
-Experiment. Swimmers will differ in their preferences when it comes to flavor, texture, palatability (feel of food in the mouth) and digestive tolerance. Test energy bars and gels in real life settings. Avoid mixed bars immediately before and during workout, as the higher fat content may slow digestion and/or upset your stomach. The same applies for bars that are high in fiber, >5 g. Do not wait until meet day to take your first bite. In doing this, you risk experiencing adverse effects, which could include, among other possible side affects, nausea, cramping, and unanticipated bathroom visits!
-Beware of Extra “Stuff.” Many manufacturers claim that the extra vitamins and minerals they have conveniently added to their product are critical for the energy boost. The fact is that the energy a swimmer gets from a sports bar or gel comes from the calories it provides. While the importance of vitamins and minerals for proper body functioning cannot be denied, adequate amounts of these nutrients can be obtained by consuming a variety of foods from all of the foods groups on a daily basis. In addition, many of the “extra” ingredients supplied in these products may not be ones a competitive athlete wants or needs to ingest. Be extra cautious of herbal ingredients.
-Read the Ingredients. This tip is simple, but it is extremely important! You must be aware of what you are eating. Pay particular attention to the ingredients list on every individual package, and avoid products that may contain substances that you know or even think may appear on the prohibited substance list. Sometimes fortified products contain even more than what actually appears on the list. It is possible. It does happen. It is your responsibility.
-Eat “Real Food.” While bars, drinks and gels provide a convenient way to get the extra calories necessary to keep pace with the swimmer’s lifestyle, it is critical to eat a variety of foods from all of the food groups every day. Use energy bars and gels only to compliment a well-balanced diet when energy demands are high and “real food” is not an option.
For additional information on issues related to this review, visit the following web links:
-Laboratory Evaluation of Nutrition Bars:
http://www.consumerlab.com/results/nutbars.asp
-Laboratory Evaluation of Powders and Drinks:
http://www.consumerlab.com/results/nutdrinks.asp
Recommended Reading
-American College of Sports Medicine. (1996). American College of Sports Medicine position stand: Exercise and fluid replacement. Medicine and Science in Sports Medicine 28(1):i-vii.
-Coombes, J.S. and K.L. Hamilton. (2000). The effectiveness of commercially available sports drinks. Sports Medicine 29(3):181-209.
-Cunningham, J.J. (1997). Is potassium needed in sports drinks for fluid replacement during exercise? International Journal of Sport Nutrition 7:154-159.
-Gleeson, M. and N.C. Bishop. (2000). Modification of immune responses to exercise by carbohydrate, glutamine and anti-oxidant supplements. Immunology and Cell Biology 78:554-561.
-Green, G.A., D. H. Catlin and B. Starcevic. (2001). Analysis of over-the-counter dietary supplements. Clinical Journal of Sport Medicine 11:254-259.
-Harvard University. (2000). Power in a bar or procey snack? Harvard Women’s Health Watch July:6.
-Leiper, J.B. (1998). Intestinal water absorption – implications for the formulation of rehydration solutions. International Journal of Sports Medicine 19:S129-S132.
-Maughan, R.J. (1998). The sports drink as a functional food: formulations for successful performance. Proceedings of the Nutrition Society 57:15-23.
-Murray, R. (1998). Rehydration strategies – balancing substrate, fluid, and electrolyte provision. International Journal of Sports Medicine 19:S133-S135.
-Ryan, M. (1997). Sports drinks: research asks for reevaluation of current recommendations. Journal of the American Dietetics Association 97(suppl):S197- S198.
-Tufts University. (2001). Why most energy bars should not go home with most people. Tufts University Health and Nutrition Letter 19(5):6.
Tuesday, May 8, 2007
Nutrition Periodization
Nutrition Periodization
By Bob Seebohar, MS, RD, CSCS .
From Olympic Coach Winter 2004.
-
Many endurance athletes structure their physical training based on Periodization principles in order to achieve peak performance during their competitive season. While many endurance athletes watch what they eat and sometimes maintain very strict, or even superstitious eating habits, many do not employ the periodization principle to the nutrition aspect of their training. More often than not, athletes are physically and mentally prepared for competition, but lack the ability to structure their eating throughout the year based on their physical training cycles. Nutrition periodization is very important for any endurance athlete. By following the principles outlined below, the endurance athlete can use the food they eat to not only provide the energy needed to support their physical training and maintain adequate glycogen stores, but also use food to maintain a healthy immune system and ward off illness, prevent vitamin and mineral deficiencies, speed recovery from hard training sessions, lose or gain weight, and positively alter body composition.
The following nutrition periodization principles are separated into the different physical training cycles that endurance athletes, young or old, novice or elite, will encounter throughout a training year.
Some of dietary recommendations listed in each cycle can be applied to other cycles but they are categorized under their
most applicable cycle below.
BASE (or Preparatory) CYCLE:
“Do’s”
-Eat a minimum of six to eight servings of fruit and vegetables per day to ensure an adequate intake of vitamins and minerals.
-Choose high fiber foods. Insoluble fiber promotes regularity while soluble fiber helps to lower cholesterol levels. While regularity may not seem beneficial during this cycle, the consequences could be great. Constipation can cause severe bowel distress and can lead to stomachaches, which may lead to missed training sessions.
-Experiment with new foods. Experiment with different energy bars, gels and sports drinks during this stage in order to choose the products that work best to use in later cycles.
Along with the above suggestion, try to find out what nutritional products will be used at races and try them. Longer endurance races (3 hours or more) usually require food and fluid assistance from the race volunteers, so be sure to try these products before using them. For endurance races lasting one to three hours, it is possible to carry adequate food and fluids and not depend on race course assistance.
“Don’ts”
-Forget about the environment. If it is cold, it is still necessary to drink adequate fluid-enough to produce a clear to lemonade color urine throughout the day.
-Get in the rut of eating the same thing everyday. Rotate through different foods and menus in order to promote more variety and balance.
INTENSITY (or Build) CYCLE
“Do’s”
-Choose the energy bars, gels and sports drinks that worked best in the last cycle and use them for the remainder of the season.
-Eat often—at least six times per day. Snacking is beneficial in this cycle in order to maintain blood glucose levels.
-Think about using salt tablets or additional electrolyte replacements. Depending on the environmental conditions, these could be of benefit. Try them during your training sessions when the environmental conditions are challenging. Salt tablets are not recommended for all athletes, so be sure to experiment first.
“Don’ts”
-Skimp on the calories. More than likely, training intensity has increased and nutritional intake must also be increased to support this level of training.
PEAK (Taper) CYCLE
“Do’s”
-Think about a lower fiber diet for longer distance races in order to decrease bowel movements during a race. Fruit juice is a great choice since there is no fiber and it contains adequate vitamins and minerals.
-Keep hydrated.
-Add extra salt to your diet for races that will last longer than four hours. Begin about two weeks before the event and be generous with the salt shaker. For a healthy athlete, it would be safe to add an extra 1⁄2 –1 teaspoon of salt per day. This is considering that there are no pre-existing health conditions that could be affected by an increased sodium intake and that fluid intake is proportionately increased at the same time.
“Don’ts”
-Try anything new.
-Form a new eating routine. Stick with what has worked in the past two cycles.
RACE CYCLE
“Do’s”
-Stick with the energy bars, gels and sports drinks that have worked during the base, intensity, and peak cycles.
-Develop a pre-race eating routine with specific foods and beverages and specific timing of foods.
-Increase calories and carbohydrates the week or weeks leading up to a race and have the largest carbohydrate rich meal two to three nights before a race (not the night before since the simple rules of digestion suggest the improbability of the food being fully digested and out of the digestive tract by race day).
-Continually snack on high carbohydrate foods the day before a race. Eat every couple of hours.
-Eat breakfast. Energy stores are low in the morning due to the overnight fast so it is important to replenish the calories used during the sleep hours (for brain function, heartbeat, and breathing).
“Don’ts”
-Try anything new, especially on race day.
-Carbo-load the night before a race. It takes 24–72 hours to fully digest a meal (from entry to exit) depending on the composition and quantity of food eaten.
-Drink too much water. Hyponatremia can develop as a result of consuming too much water because it displaces extra-cellular sodium. This is why drinking a sport drink is of benefit.
ACTIVE RECOVERY OR (TRANSITION) CYCLE
“Do’s”
-Put the energy bars, gels and sports drinks in the back of the cupboard for a while to give the body a break from them.
-Re-introduce whole foods from all of the food groups to acquire vitamins and minerals from foods rather than bars, gels, and drinks.
-Try new restaurants and foods. Be adventurous and think outside of the box. Foods prepared a different way or from a different culture are good sources of nutrients and provide a break from the “norm.”
-Try to lose weight safely and realistically. Since there is not much structure or strict training guidelines during this cycle, a weight loss of one to two pounds per week is safe, realistic, and will not have a negative impact on training.
“Don’ts”
-Overeat. It is very easy to gain weight in the off-season without realizing it. A weight gain of two pounds per month can happen by simply overeating by 250 calories per day!
-Forget about the environment. If this cycle falls in the winter where there is not much sunshine, it is common to eat more comfort foods, which can be very high in calories and tend to increase body weight and body fat.
THE FOLLOWING NUTRITION PRINCIPLES APPLY YEARROUND REGARDLESS OF TRAINING CYCLE:
“Do’s”
-Choose foods rich in beta-carotene, vitamin C, vitamin E and zinc to improve immune function. -Current research studies lend support that these vitamins and minerals may be of benefit to improve immune function, although the data is still inconclusive.
-Choose more polyunsaturated (fish) and monounsaturated (nuts, canola and olive oil, avocados, olives) fats rather than saturated fats (high-fat meats, butter, lard, processed foods such as cookies and chips) for improved heart functioning.
-Consume a high-glycemic index carbohydrate source (baked potato, vanilla wafers, jelly beans, watermelon, bagel) combined with a lean protein within the first 15 minutes after training or a race. Examples are a sports drink with a cup of yogurt, watermelon and chocolate milk, a lean meat sandwich minus the mayo. There are also commercially available products that provide the same effect. Some promising research has shown that a ratio of 4:1 carbohydrates to protein is beneficial for enhancing glycogen storage and quicker recovery.
-Think about taking a multivitamin that has no more than 100-200% Daily Value (DV) for nutrients (a child’s chewable multivitamin/mineral is perfect for adults).
-Remember, you are also eating energy bars and supplements chock full of vitamins and minerals so your multivitamin does not need to contain mega doses.
-Keep a written three to five day food diary every four weeks to keep on track with the quantity and variety of food eaten. Seeing the amount of food eaten on paper provides good feedback of dietary habits and could prevent over- or under-eating.
-Listen to the body. If it craves something, chances are that it needs the nutrients in that food.
When more assistance is needed, locate a registered dietitian who specializes in sports nutrition.
“Don’ts”
-Restrict your eating to a few food groups. This may lead to nutritional deficiencies in the future.
Consume too much fat after a training session or a race. Because fat is preferentially oxidized over carbohydrates, it can slow the absorption of carbohydrates and can slow the recovery process.
-Take any nutritional supplement that has not been researched in credible scientific journals or whose effects are unknown. Taking a nutritional supplement without knowing its full effects could actually lead to a decrease in performance, termed ergolytic rather than ergogenic. There are not many proven nutritional supplements that produce positive effects for endurance athletes.
-Believe a product or a specific way of eating is the only way to achieve success just because a training partner, friend or family member uses or follows it. Each person and athlete is different. -Use the information gained from scientific research combined with trial and error to determine the best option.
-Worry about protein intake. Athletes who eat an adequate amount of food to support training will more than often consume more than enough protein to support training and recovery. Exceptions are true vegans or those who do not consume enough calories.
By combining the above nutrition periodization principles to an already periodized physical training program, the endurance athlete will undoubtedly be able to perform at the highest level of human performance possible for their body.
Bob Seebohar is the Director of the Colorado Altitude Training and Performance Center in Evergreen, Colorado. He is a Sports Dietitian, an Exercise Physiologist and a USA Triathlon Certified Expert Coach.
By Bob Seebohar, MS, RD, CSCS .
From Olympic Coach Winter 2004.
-
Many endurance athletes structure their physical training based on Periodization principles in order to achieve peak performance during their competitive season. While many endurance athletes watch what they eat and sometimes maintain very strict, or even superstitious eating habits, many do not employ the periodization principle to the nutrition aspect of their training. More often than not, athletes are physically and mentally prepared for competition, but lack the ability to structure their eating throughout the year based on their physical training cycles. Nutrition periodization is very important for any endurance athlete. By following the principles outlined below, the endurance athlete can use the food they eat to not only provide the energy needed to support their physical training and maintain adequate glycogen stores, but also use food to maintain a healthy immune system and ward off illness, prevent vitamin and mineral deficiencies, speed recovery from hard training sessions, lose or gain weight, and positively alter body composition.
The following nutrition periodization principles are separated into the different physical training cycles that endurance athletes, young or old, novice or elite, will encounter throughout a training year.
Some of dietary recommendations listed in each cycle can be applied to other cycles but they are categorized under their
most applicable cycle below.
BASE (or Preparatory) CYCLE:
“Do’s”
-Eat a minimum of six to eight servings of fruit and vegetables per day to ensure an adequate intake of vitamins and minerals.
-Choose high fiber foods. Insoluble fiber promotes regularity while soluble fiber helps to lower cholesterol levels. While regularity may not seem beneficial during this cycle, the consequences could be great. Constipation can cause severe bowel distress and can lead to stomachaches, which may lead to missed training sessions.
-Experiment with new foods. Experiment with different energy bars, gels and sports drinks during this stage in order to choose the products that work best to use in later cycles.
Along with the above suggestion, try to find out what nutritional products will be used at races and try them. Longer endurance races (3 hours or more) usually require food and fluid assistance from the race volunteers, so be sure to try these products before using them. For endurance races lasting one to three hours, it is possible to carry adequate food and fluids and not depend on race course assistance.
“Don’ts”
-Forget about the environment. If it is cold, it is still necessary to drink adequate fluid-enough to produce a clear to lemonade color urine throughout the day.
-Get in the rut of eating the same thing everyday. Rotate through different foods and menus in order to promote more variety and balance.
INTENSITY (or Build) CYCLE
“Do’s”
-Choose the energy bars, gels and sports drinks that worked best in the last cycle and use them for the remainder of the season.
-Eat often—at least six times per day. Snacking is beneficial in this cycle in order to maintain blood glucose levels.
-Think about using salt tablets or additional electrolyte replacements. Depending on the environmental conditions, these could be of benefit. Try them during your training sessions when the environmental conditions are challenging. Salt tablets are not recommended for all athletes, so be sure to experiment first.
“Don’ts”
-Skimp on the calories. More than likely, training intensity has increased and nutritional intake must also be increased to support this level of training.
PEAK (Taper) CYCLE
“Do’s”
-Think about a lower fiber diet for longer distance races in order to decrease bowel movements during a race. Fruit juice is a great choice since there is no fiber and it contains adequate vitamins and minerals.
-Keep hydrated.
-Add extra salt to your diet for races that will last longer than four hours. Begin about two weeks before the event and be generous with the salt shaker. For a healthy athlete, it would be safe to add an extra 1⁄2 –1 teaspoon of salt per day. This is considering that there are no pre-existing health conditions that could be affected by an increased sodium intake and that fluid intake is proportionately increased at the same time.
“Don’ts”
-Try anything new.
-Form a new eating routine. Stick with what has worked in the past two cycles.
RACE CYCLE
“Do’s”
-Stick with the energy bars, gels and sports drinks that have worked during the base, intensity, and peak cycles.
-Develop a pre-race eating routine with specific foods and beverages and specific timing of foods.
-Increase calories and carbohydrates the week or weeks leading up to a race and have the largest carbohydrate rich meal two to three nights before a race (not the night before since the simple rules of digestion suggest the improbability of the food being fully digested and out of the digestive tract by race day).
-Continually snack on high carbohydrate foods the day before a race. Eat every couple of hours.
-Eat breakfast. Energy stores are low in the morning due to the overnight fast so it is important to replenish the calories used during the sleep hours (for brain function, heartbeat, and breathing).
“Don’ts”
-Try anything new, especially on race day.
-Carbo-load the night before a race. It takes 24–72 hours to fully digest a meal (from entry to exit) depending on the composition and quantity of food eaten.
-Drink too much water. Hyponatremia can develop as a result of consuming too much water because it displaces extra-cellular sodium. This is why drinking a sport drink is of benefit.
ACTIVE RECOVERY OR (TRANSITION) CYCLE
“Do’s”
-Put the energy bars, gels and sports drinks in the back of the cupboard for a while to give the body a break from them.
-Re-introduce whole foods from all of the food groups to acquire vitamins and minerals from foods rather than bars, gels, and drinks.
-Try new restaurants and foods. Be adventurous and think outside of the box. Foods prepared a different way or from a different culture are good sources of nutrients and provide a break from the “norm.”
-Try to lose weight safely and realistically. Since there is not much structure or strict training guidelines during this cycle, a weight loss of one to two pounds per week is safe, realistic, and will not have a negative impact on training.
“Don’ts”
-Overeat. It is very easy to gain weight in the off-season without realizing it. A weight gain of two pounds per month can happen by simply overeating by 250 calories per day!
-Forget about the environment. If this cycle falls in the winter where there is not much sunshine, it is common to eat more comfort foods, which can be very high in calories and tend to increase body weight and body fat.
THE FOLLOWING NUTRITION PRINCIPLES APPLY YEARROUND REGARDLESS OF TRAINING CYCLE:
“Do’s”
-Choose foods rich in beta-carotene, vitamin C, vitamin E and zinc to improve immune function. -Current research studies lend support that these vitamins and minerals may be of benefit to improve immune function, although the data is still inconclusive.
-Choose more polyunsaturated (fish) and monounsaturated (nuts, canola and olive oil, avocados, olives) fats rather than saturated fats (high-fat meats, butter, lard, processed foods such as cookies and chips) for improved heart functioning.
-Consume a high-glycemic index carbohydrate source (baked potato, vanilla wafers, jelly beans, watermelon, bagel) combined with a lean protein within the first 15 minutes after training or a race. Examples are a sports drink with a cup of yogurt, watermelon and chocolate milk, a lean meat sandwich minus the mayo. There are also commercially available products that provide the same effect. Some promising research has shown that a ratio of 4:1 carbohydrates to protein is beneficial for enhancing glycogen storage and quicker recovery.
-Think about taking a multivitamin that has no more than 100-200% Daily Value (DV) for nutrients (a child’s chewable multivitamin/mineral is perfect for adults).
-Remember, you are also eating energy bars and supplements chock full of vitamins and minerals so your multivitamin does not need to contain mega doses.
-Keep a written three to five day food diary every four weeks to keep on track with the quantity and variety of food eaten. Seeing the amount of food eaten on paper provides good feedback of dietary habits and could prevent over- or under-eating.
-Listen to the body. If it craves something, chances are that it needs the nutrients in that food.
When more assistance is needed, locate a registered dietitian who specializes in sports nutrition.
“Don’ts”
-Restrict your eating to a few food groups. This may lead to nutritional deficiencies in the future.
Consume too much fat after a training session or a race. Because fat is preferentially oxidized over carbohydrates, it can slow the absorption of carbohydrates and can slow the recovery process.
-Take any nutritional supplement that has not been researched in credible scientific journals or whose effects are unknown. Taking a nutritional supplement without knowing its full effects could actually lead to a decrease in performance, termed ergolytic rather than ergogenic. There are not many proven nutritional supplements that produce positive effects for endurance athletes.
-Believe a product or a specific way of eating is the only way to achieve success just because a training partner, friend or family member uses or follows it. Each person and athlete is different. -Use the information gained from scientific research combined with trial and error to determine the best option.
-Worry about protein intake. Athletes who eat an adequate amount of food to support training will more than often consume more than enough protein to support training and recovery. Exceptions are true vegans or those who do not consume enough calories.
By combining the above nutrition periodization principles to an already periodized physical training program, the endurance athlete will undoubtedly be able to perform at the highest level of human performance possible for their body.
Bob Seebohar is the Director of the Colorado Altitude Training and Performance Center in Evergreen, Colorado. He is a Sports Dietitian, an Exercise Physiologist and a USA Triathlon Certified Expert Coach.
Making Weight
Nutrition – Making Weight and Sports Performance
Irish National Sports Information Service Fact Sheet 8
-
What is Making Weight
‘Making weight’ is the practice used by weight-class athletes to lose weight in order to compete. In weight-class sports, which include, among others, boxing, lightweight rowing, weightlifting, wrestling, judo and other combat sports, athletes must meet a certain weight classification to compete. Patterns of weight fluctuation vary among athletes. Some athletes chronically maintain a low body weight, whereas others lose weight for the competitive season and regain in the off-season. Conversely, some sports such as the Olympic sailing classes appear to have an optimum competitive weight, which may require athletes to gain weight to perform effectively (McCargar et al 1993).
How Do Athletes Make Weight
If an athlete needs to ‘make weight’ for a competition, the most common weight reduction strategy is rapid weight loss (within the week before the competition). Weight loss methods are varied and include severe dieting or starvation, fluid restriction, passive (sauna) or active (exercise in “sweat suits) dehydration, and the use of diuretics, laxatives, or self-induced vomiting. These rapid weight-making techniques reduce weight, principally by decreasing body fluids, food in the gastrointestinal tract and muscle energy stores (Fogelholm, 1994).
Implicatons Of Rapid Weight Loss
• Dangers and effects of rapid weight loss
There are two major health risks involved in losing weight rapidly for athletic competition: malnutrition and dehydration. Dehydration is the excessive loss of water from the body, which results in impairments in performance and proper body function. Malnutrition is caused by inadequate intake of nutrients. Dehydration is the most acute and the most dangerous. When rapid weight loss techniques are used, primarily water and lean body mass is lost, not fat. Muscle carbohydrate stores (glycogen) and muscle water are decreased. This impairs temperature regulation and cardiovascular function. A rapid reduction in weight will affect strength and endurance capacity and ultimately impact on performance. Rapid weight loss may result in psychological changes that influence performance negatively (Brownell et al, 1987).
• Short term consequences
There are a number of consequences associated with rapid excessive weight loss, which include mood swings, lack of energy and lack of motivation, which can all contribute to impairments in performance (Table 1). An athlete will have less energy, slowed metabolism, loss of muscle mass, strength, power and a reduced endurance capacity leading to underperformance. Additionally, there is an increased risk of mental and physical exhaustion. The most extreme consequence of rapid excessive weight loss (of greater than 10%) may result in collapse and possible death. In 1997, three collegiate wrestlers died, while attempting rapid weight loss for their weight-class certifications (MMWR, 1998).
• Long term consequences
Athletes who strive to maintain body weight or body fat levels that are inappropriate, or have body-fat percentages below minimal, may be at risk for an eating disorder, such as anorexia nervosa or bulimia nervosa, or other health problems related to poor energy and nutrient intakes. The levels of body fat considered to be minimal levels compatible with good health are 5% for males and 12% for females (Lohman, 1992). However, the ranges of body fat for athletes vary by sport and by gender within a sport. Athletes should typically aim to maintain body fat levels within ranges of 8–12% for males and 16–20% for females. In addition, vitamin and mineral deficiencies may develop long-term due to an inadequate nutrient intake, and an athlete may experience changes to hormonal and metabolic function. These consequences not only damage athletic performance but may also have serious overall health implications.
• Dehydration
Dehydration is often used as a quick way to 'make weight'. Rapid weight loss by fluid restriction leads to dehydration—not fat loss. Fluid loss of as little as 1% of body weight (0.7 kg in a 70 kg person) has shown to decrease endurance performance. Rehydration strategies may negate this effect where sufficient time is allowed. Small to moderate water losses (2% to 4% of body weight) result in reduced maximal aerobic capacity (VO2max). A 2% decrease in body weight has been shown to impair endurance performance by 20% (Ivy et al 1988). Yet, in boxing, a 2% rapid weight loss strategy is relatively common without appropriate subsequent rehydration (Smith et al, 2000).
As the percentage of body weight lost as a result of fluid reduction increases, so too do the dangerous consequences of dehydration caused by the inability of the body to effectively regulate temperature. Dehydration increases the risk of heat injury, including muscle cramps, heat exhaustion, and heat stroke. Early signs of dehydration include nausea, dizziness, fatigue, and difficulty concentrating. Though you can largely rehydrate in 12 hours, it takes 24 - 48 hours for full rehydration.
It should be noted that if 1kg has been lost then rehydration of up to 1.5 litres of fluid is appropriate when also taking into consideration the production of urine. In these instances, isotonic drinks are the favoured option as the body absorbs them more readily than water and less of the fluid is lost in urine production
Note: Diuretics and Vomiting
As well as loss of fluid, diuretics also give rise to a loss of sodium and chloride from the blood, and potassium and magnesium from muscle cells. Losses of minerals and water increase the risk of muscle cramps and spasm.
The use of diuretics is not recommended, and is banned by many sports federations, including the IOC. Similarly, athletes who use vomiting and diarrhoea to lose weight rapidly not only induce dehydration but also cause excessive mineral loss with accompanying muscle weakness and impaired neuromuscular function.
Healthy Weight Loss
The healthiest way to lose weight is slowly, which is planned and controlled over a prolonged period of time and allows proper hydration and good nutritional practices. The only way to safely and effectively lose fat and preserve muscle is through modest calorie restriction and exercise.
Crash dieting is unhealthy for your body and detrimental to your performance.
An athlete should not reduce their energy intake below 1200–1500 kcal/day (4–6 MJ per day) unless supervised by a sports dietician (American Heart Association, 1994)
Weight Cycling
Repeated cycles of weight loss and regain is referred to as ‘weight cycling.’ In addition to impaired athletic performance, other consequences of weight cycling include a decrease in resting metabolic rate (which makes it harder to lose weight the next time), altered body composition, with increased ratio of fat to lean tissue, altered fat deposition, with greater abdominal fat relative to femoral fat, altered hormone profiles and possible nutrient deficiencies.
Summary Points For Weight (Fat) Loss Or Making Weight
Ø Weight reduction/fat loss is best achieved by combining moderate food restriction with additional physical activity. This allows the athlete to train and compete optimally.
Ø Choose a body fat/weight that keeps you healthy in the long term and allows you to train and compete optimally.
Ø Choose a balanced diet, emphasising a high carbohydrate (60-70%) and a modest-low protein (10-15%) and fat (25-30%) intake.
Ø Eat a little less energy (kilojoules/calories) than you burn in training or competition to achieve a slight calorie deficit, and therefore a healthy weight (or body fat) loss. (Reducing food intake by 500 kilocalories/day
Ø should result in the loss of 1-2 lbs/week).
Ø Do not 'crash' diet.
Ø Be wary of times when weight (fat) levels may fluctuate more e.g. 'off season' or when injured. Monitor these changes and adjust your dietary intake and training to suit.
Ø Gradually reduce weight by setting realistic targets (not more than 0.5-1.0 kg [1-2 lb] per week) each week.
Ø Monitor your weight regularly, at the same time of day using accurate scales.
Ø Seek professional advice from a sports dietician and a sports scientist on dietary requirements for your sport, or whether a weight category or body fat level is realistic for your physique.
Athletes Who May Require Specialist Weight Control Advise
Ø Athletes returning from injury or a break from their sport where inactivity has lead to body fat/weight gain.
Ø Athletes competing in a weight-controlled sport who wish to compete in a weight division that is below their current weight, e.g. Boxing, weight-lifting, light-weight rowing, wrestling.
Ø Athletes competing in an endurance sport or power sport where a low body fat level and an increased power to weight ratio, is a physical advantage to performance, e.g. Distance running, cycling, triathlons, gymnastics.
Ø Athletes competing in a sport where leanness and low body fat levels are of aesthetic advantage, e.g. Gymnastics, diving, ballet, body building.
Ø Athletes competing in a skill-based sport where training hours are lengthy but essentially low-energy expenditure (and therefore do not contribute to a high energy turnover). The athletes may desire to lose weight for health and aesthetic reasons, e.g. Golf, archery.
Ø Athletes who have been required by their sport to move away from a stable home environment. These athletes may have poor cooking/food preparation skills, lead an irregular and/or disorganised life-style, and be reliant on takeaway and restaurant meals, e.g. Rugby and other team sports, tennis and other sports requiring extensive travel. Source:Burke, 1994
Recommendations
The daily caloric intake should be obtained from a balanced diet high in carbohydrates (60-70% of calories), low in fat (25-30% of calories) and adequate protein (10-15% of calories).
Handy Hints For Weight Loss
Ø The healthiest method of weight loss is to reduce weight gradually and to be as close as possible (ideally, no more than 1-2%) to the competition weight.
Ø It is very important to have a well balanced diet, which includes all nutrients in order to avoid any lack in particular nutrients.
Ø Refer to the food pyramid for the numbers of servings needed (Fig 1) for each food group per day.
Ø Athletes should at least consume the minimum number of recommended servings from each food group on the pyramid.
Ø In addition, consultation with a sports nutritionist/dietician may be important in order to individualise weight loss strategies.
WHAT IS A SERVING?
Bread, cereal, rice and pasta group
• 1 slice of bread
• cup of cooked rice or pasta (125g)
• cup of cooked cereal
• Medium bowl of breakfast cereal
Vegetable group
• cup of cooked or raw vegetables
• 1 cup of leafy raw vegetables
• 1 cup of tomato or vegetable juice (about 1 glass)
• Medium bowl of vegetable or tomato soup
Fruit group
• 1 piece of fruit (i.e. 1 banana, 1 apple etc.)
• or 1 piece of melon wedge
• 1 glass of juice (about 200ml)
• cup of canned fruit
• cup of dried fruit
Milk, Yoghurt and Cheese group
• 250ml milk or yoghurt (average glass is 200ml)
• 35g natural cheese (medium chunk)
• 60g processed cheese (3 slices)
Meat, fish, poultry, eggs, dry beans and nuts group
• 60-85g (2-3 oz) of cooked lean meat, poultry or fish (Examples: small portion of mince beef = 100g, average portion of roast beef = 100g, average chicken breast = 100g, slice of ham = 25g)
• cup of cooked dry beans
• 1 egg
• 3 tablespoons of nuts
Weight Gain
Gaining weight can be quite difficult. In addition, to the calories needed to meet the demands of training and competition extra calories are required to increase body mass. Similar guidelines to those found in the recommendations for athletes are advised, i.e. high in carbohydrate and moderate to low in fat and protein respectively (Burke and Inge, 1994). It is important to eat 6-8 times per day in order to gain weight. This should consist of 3 main meals and 3-4 snacks during the day. It should be noted, that although carbohydrate provides only 4 calories per gram compared to fat, which provides 9 calories per gram. Athletes should still look to carbohydrate rather than fat to achieve weight gain. Fat is not the desirable or recommended energy source for athletes. Carbohydrate is the only fuel that can power intense exercise for prolonged periods. An additional 500 Kcal per day will result in weight gain of about 1-2 lbs per week. However, where increased amounts of carbohydrate is being consumed in the absence of activity, it should be noted that carbohydrate may be converted to fat which subsequently would result in increased levels of body fat. Resistance training is essential for athletes looking to gain muscle mass rather than fat. Weight training stimulates muscle growth when adequate energy is available. It is of importance to note, when engaging in weight training programmes, that adequate rest and sleep is imperative for muscle growth and regeneration.
Protein requirement is slightly increased when resistance training is increased. However, a diet containing meat, poultry, fish and dairy products more than meets this slight increase in demand. Athletes consuming a well balanced diet do not need protein supplements to increase muscle mass. In fact such supplements often result in fat deposition rather than increased muscle mass.
Endurance athletes require about 1.3-1.4g of protein per kg of body weight (for a 100 kg athlete this is about 135g of protein per day). Strength athletes require between 1.4-1.8g of protein per kg of body weight (for a 100kg athlete this is about 160g protein per day).
Handy Hints for Weight Gain
Ø Athletes should plan in advance and have snacks on hand in gear bags, cars etc. eg. bananas, sandwiches or Fig Rolls bars.
Ø Athletes should consume a certain amount of their calories from liquid, to contribute to the increase in calorie intake and consequently weight gain, e.g. Squashes or cordials (non-sugar free), sports drinks (up to a litre a day), fruit juices, banana/fruit smoothies, yoghurt based drinks.
Ø In order to gain weight this increased food intake should be carried out consistently. If weight gain practice is only carried out 3 days per week and then forgotten about, it will negate the weight gain process. Consistency is important to gain weight effectively. Keep a diary of daily food intake along with a record of rest taken. This helps to monitor the additional calorie intake.
Ø Athletes need to eat, drink, rest and carry out relevant training, i.e. NOT additional or other activities, in order to allow the process to occur.
Ø Use of legal supplements should only be considered after consultation with a sports doctor or nutritionist.
Ø A specific hypertrophy (muscle building) weight-training programme should be incorporated. For specific information you should consult a strength and conditioning specialist.
Ø Seek advice from a nutritionist or a sports dietician for individualized diet plans.
Further Reading
1. American College of Sports Medicine. (1983). Proper and Improper Weight Loss Programs, Medicine and Science in Sports and Exercise, 15(1), ix-xiii
2. Brownell KD, Steen SN, & Wilmore JH. (1987). Weight regulation practices in athletes: analysis of metabolic and health effects. Medicine and Science in Sports and Exercise, 19(6), 546-556.
3. Burke L, Inge K (1994) Protein requirements for training and ‘bulking up’ (pp 124-150) ). In: Clinical Sports Nutrition Burke L, Deakin V Eds. Sydney: McGraw Hill Book Company
4. Fogelholm GM. (1994). Effects of Bodyweight Reduction on Sports Performance. Sports Medicine, 18(4), 249-267.
5. Greenleaf JE. (1992). Problem: thirst, drinking behaviour, and involuntary dehydration, Medicine and Science in Sports and Exercise, 24(6), 645-656
6. McCargar LJ; Simmons D; Craton N; Taunton JE; Birmingham C (1993). Physiological effects of weight cycling in female lightweight rowers, Canadian Journal of Applied Physiology, 18(3), 291-303
Irish National Sports Information Service Fact Sheet 8
-
What is Making Weight
‘Making weight’ is the practice used by weight-class athletes to lose weight in order to compete. In weight-class sports, which include, among others, boxing, lightweight rowing, weightlifting, wrestling, judo and other combat sports, athletes must meet a certain weight classification to compete. Patterns of weight fluctuation vary among athletes. Some athletes chronically maintain a low body weight, whereas others lose weight for the competitive season and regain in the off-season. Conversely, some sports such as the Olympic sailing classes appear to have an optimum competitive weight, which may require athletes to gain weight to perform effectively (McCargar et al 1993).
How Do Athletes Make Weight
If an athlete needs to ‘make weight’ for a competition, the most common weight reduction strategy is rapid weight loss (within the week before the competition). Weight loss methods are varied and include severe dieting or starvation, fluid restriction, passive (sauna) or active (exercise in “sweat suits) dehydration, and the use of diuretics, laxatives, or self-induced vomiting. These rapid weight-making techniques reduce weight, principally by decreasing body fluids, food in the gastrointestinal tract and muscle energy stores (Fogelholm, 1994).
Implicatons Of Rapid Weight Loss
• Dangers and effects of rapid weight loss
There are two major health risks involved in losing weight rapidly for athletic competition: malnutrition and dehydration. Dehydration is the excessive loss of water from the body, which results in impairments in performance and proper body function. Malnutrition is caused by inadequate intake of nutrients. Dehydration is the most acute and the most dangerous. When rapid weight loss techniques are used, primarily water and lean body mass is lost, not fat. Muscle carbohydrate stores (glycogen) and muscle water are decreased. This impairs temperature regulation and cardiovascular function. A rapid reduction in weight will affect strength and endurance capacity and ultimately impact on performance. Rapid weight loss may result in psychological changes that influence performance negatively (Brownell et al, 1987).
• Short term consequences
There are a number of consequences associated with rapid excessive weight loss, which include mood swings, lack of energy and lack of motivation, which can all contribute to impairments in performance (Table 1). An athlete will have less energy, slowed metabolism, loss of muscle mass, strength, power and a reduced endurance capacity leading to underperformance. Additionally, there is an increased risk of mental and physical exhaustion. The most extreme consequence of rapid excessive weight loss (of greater than 10%) may result in collapse and possible death. In 1997, three collegiate wrestlers died, while attempting rapid weight loss for their weight-class certifications (MMWR, 1998).
• Long term consequences
Athletes who strive to maintain body weight or body fat levels that are inappropriate, or have body-fat percentages below minimal, may be at risk for an eating disorder, such as anorexia nervosa or bulimia nervosa, or other health problems related to poor energy and nutrient intakes. The levels of body fat considered to be minimal levels compatible with good health are 5% for males and 12% for females (Lohman, 1992). However, the ranges of body fat for athletes vary by sport and by gender within a sport. Athletes should typically aim to maintain body fat levels within ranges of 8–12% for males and 16–20% for females. In addition, vitamin and mineral deficiencies may develop long-term due to an inadequate nutrient intake, and an athlete may experience changes to hormonal and metabolic function. These consequences not only damage athletic performance but may also have serious overall health implications.
• Dehydration
Dehydration is often used as a quick way to 'make weight'. Rapid weight loss by fluid restriction leads to dehydration—not fat loss. Fluid loss of as little as 1% of body weight (0.7 kg in a 70 kg person) has shown to decrease endurance performance. Rehydration strategies may negate this effect where sufficient time is allowed. Small to moderate water losses (2% to 4% of body weight) result in reduced maximal aerobic capacity (VO2max). A 2% decrease in body weight has been shown to impair endurance performance by 20% (Ivy et al 1988). Yet, in boxing, a 2% rapid weight loss strategy is relatively common without appropriate subsequent rehydration (Smith et al, 2000).
As the percentage of body weight lost as a result of fluid reduction increases, so too do the dangerous consequences of dehydration caused by the inability of the body to effectively regulate temperature. Dehydration increases the risk of heat injury, including muscle cramps, heat exhaustion, and heat stroke. Early signs of dehydration include nausea, dizziness, fatigue, and difficulty concentrating. Though you can largely rehydrate in 12 hours, it takes 24 - 48 hours for full rehydration.
It should be noted that if 1kg has been lost then rehydration of up to 1.5 litres of fluid is appropriate when also taking into consideration the production of urine. In these instances, isotonic drinks are the favoured option as the body absorbs them more readily than water and less of the fluid is lost in urine production
Note: Diuretics and Vomiting
As well as loss of fluid, diuretics also give rise to a loss of sodium and chloride from the blood, and potassium and magnesium from muscle cells. Losses of minerals and water increase the risk of muscle cramps and spasm.
The use of diuretics is not recommended, and is banned by many sports federations, including the IOC. Similarly, athletes who use vomiting and diarrhoea to lose weight rapidly not only induce dehydration but also cause excessive mineral loss with accompanying muscle weakness and impaired neuromuscular function.
Healthy Weight Loss
The healthiest way to lose weight is slowly, which is planned and controlled over a prolonged period of time and allows proper hydration and good nutritional practices. The only way to safely and effectively lose fat and preserve muscle is through modest calorie restriction and exercise.
Crash dieting is unhealthy for your body and detrimental to your performance.
An athlete should not reduce their energy intake below 1200–1500 kcal/day (4–6 MJ per day) unless supervised by a sports dietician (American Heart Association, 1994)
Weight Cycling
Repeated cycles of weight loss and regain is referred to as ‘weight cycling.’ In addition to impaired athletic performance, other consequences of weight cycling include a decrease in resting metabolic rate (which makes it harder to lose weight the next time), altered body composition, with increased ratio of fat to lean tissue, altered fat deposition, with greater abdominal fat relative to femoral fat, altered hormone profiles and possible nutrient deficiencies.
Summary Points For Weight (Fat) Loss Or Making Weight
Ø Weight reduction/fat loss is best achieved by combining moderate food restriction with additional physical activity. This allows the athlete to train and compete optimally.
Ø Choose a body fat/weight that keeps you healthy in the long term and allows you to train and compete optimally.
Ø Choose a balanced diet, emphasising a high carbohydrate (60-70%) and a modest-low protein (10-15%) and fat (25-30%) intake.
Ø Eat a little less energy (kilojoules/calories) than you burn in training or competition to achieve a slight calorie deficit, and therefore a healthy weight (or body fat) loss. (Reducing food intake by 500 kilocalories/day
Ø should result in the loss of 1-2 lbs/week).
Ø Do not 'crash' diet.
Ø Be wary of times when weight (fat) levels may fluctuate more e.g. 'off season' or when injured. Monitor these changes and adjust your dietary intake and training to suit.
Ø Gradually reduce weight by setting realistic targets (not more than 0.5-1.0 kg [1-2 lb] per week) each week.
Ø Monitor your weight regularly, at the same time of day using accurate scales.
Ø Seek professional advice from a sports dietician and a sports scientist on dietary requirements for your sport, or whether a weight category or body fat level is realistic for your physique.
Athletes Who May Require Specialist Weight Control Advise
Ø Athletes returning from injury or a break from their sport where inactivity has lead to body fat/weight gain.
Ø Athletes competing in a weight-controlled sport who wish to compete in a weight division that is below their current weight, e.g. Boxing, weight-lifting, light-weight rowing, wrestling.
Ø Athletes competing in an endurance sport or power sport where a low body fat level and an increased power to weight ratio, is a physical advantage to performance, e.g. Distance running, cycling, triathlons, gymnastics.
Ø Athletes competing in a sport where leanness and low body fat levels are of aesthetic advantage, e.g. Gymnastics, diving, ballet, body building.
Ø Athletes competing in a skill-based sport where training hours are lengthy but essentially low-energy expenditure (and therefore do not contribute to a high energy turnover). The athletes may desire to lose weight for health and aesthetic reasons, e.g. Golf, archery.
Ø Athletes who have been required by their sport to move away from a stable home environment. These athletes may have poor cooking/food preparation skills, lead an irregular and/or disorganised life-style, and be reliant on takeaway and restaurant meals, e.g. Rugby and other team sports, tennis and other sports requiring extensive travel. Source:Burke, 1994
Recommendations
The daily caloric intake should be obtained from a balanced diet high in carbohydrates (60-70% of calories), low in fat (25-30% of calories) and adequate protein (10-15% of calories).
Handy Hints For Weight Loss
Ø The healthiest method of weight loss is to reduce weight gradually and to be as close as possible (ideally, no more than 1-2%) to the competition weight.
Ø It is very important to have a well balanced diet, which includes all nutrients in order to avoid any lack in particular nutrients.
Ø Refer to the food pyramid for the numbers of servings needed (Fig 1) for each food group per day.
Ø Athletes should at least consume the minimum number of recommended servings from each food group on the pyramid.
Ø In addition, consultation with a sports nutritionist/dietician may be important in order to individualise weight loss strategies.
WHAT IS A SERVING?
Bread, cereal, rice and pasta group
• 1 slice of bread
• cup of cooked rice or pasta (125g)
• cup of cooked cereal
• Medium bowl of breakfast cereal
Vegetable group
• cup of cooked or raw vegetables
• 1 cup of leafy raw vegetables
• 1 cup of tomato or vegetable juice (about 1 glass)
• Medium bowl of vegetable or tomato soup
Fruit group
• 1 piece of fruit (i.e. 1 banana, 1 apple etc.)
• or 1 piece of melon wedge
• 1 glass of juice (about 200ml)
• cup of canned fruit
• cup of dried fruit
Milk, Yoghurt and Cheese group
• 250ml milk or yoghurt (average glass is 200ml)
• 35g natural cheese (medium chunk)
• 60g processed cheese (3 slices)
Meat, fish, poultry, eggs, dry beans and nuts group
• 60-85g (2-3 oz) of cooked lean meat, poultry or fish (Examples: small portion of mince beef = 100g, average portion of roast beef = 100g, average chicken breast = 100g, slice of ham = 25g)
• cup of cooked dry beans
• 1 egg
• 3 tablespoons of nuts
Weight Gain
Gaining weight can be quite difficult. In addition, to the calories needed to meet the demands of training and competition extra calories are required to increase body mass. Similar guidelines to those found in the recommendations for athletes are advised, i.e. high in carbohydrate and moderate to low in fat and protein respectively (Burke and Inge, 1994). It is important to eat 6-8 times per day in order to gain weight. This should consist of 3 main meals and 3-4 snacks during the day. It should be noted, that although carbohydrate provides only 4 calories per gram compared to fat, which provides 9 calories per gram. Athletes should still look to carbohydrate rather than fat to achieve weight gain. Fat is not the desirable or recommended energy source for athletes. Carbohydrate is the only fuel that can power intense exercise for prolonged periods. An additional 500 Kcal per day will result in weight gain of about 1-2 lbs per week. However, where increased amounts of carbohydrate is being consumed in the absence of activity, it should be noted that carbohydrate may be converted to fat which subsequently would result in increased levels of body fat. Resistance training is essential for athletes looking to gain muscle mass rather than fat. Weight training stimulates muscle growth when adequate energy is available. It is of importance to note, when engaging in weight training programmes, that adequate rest and sleep is imperative for muscle growth and regeneration.
Protein requirement is slightly increased when resistance training is increased. However, a diet containing meat, poultry, fish and dairy products more than meets this slight increase in demand. Athletes consuming a well balanced diet do not need protein supplements to increase muscle mass. In fact such supplements often result in fat deposition rather than increased muscle mass.
Endurance athletes require about 1.3-1.4g of protein per kg of body weight (for a 100 kg athlete this is about 135g of protein per day). Strength athletes require between 1.4-1.8g of protein per kg of body weight (for a 100kg athlete this is about 160g protein per day).
Handy Hints for Weight Gain
Ø Athletes should plan in advance and have snacks on hand in gear bags, cars etc. eg. bananas, sandwiches or Fig Rolls bars.
Ø Athletes should consume a certain amount of their calories from liquid, to contribute to the increase in calorie intake and consequently weight gain, e.g. Squashes or cordials (non-sugar free), sports drinks (up to a litre a day), fruit juices, banana/fruit smoothies, yoghurt based drinks.
Ø In order to gain weight this increased food intake should be carried out consistently. If weight gain practice is only carried out 3 days per week and then forgotten about, it will negate the weight gain process. Consistency is important to gain weight effectively. Keep a diary of daily food intake along with a record of rest taken. This helps to monitor the additional calorie intake.
Ø Athletes need to eat, drink, rest and carry out relevant training, i.e. NOT additional or other activities, in order to allow the process to occur.
Ø Use of legal supplements should only be considered after consultation with a sports doctor or nutritionist.
Ø A specific hypertrophy (muscle building) weight-training programme should be incorporated. For specific information you should consult a strength and conditioning specialist.
Ø Seek advice from a nutritionist or a sports dietician for individualized diet plans.
Further Reading
1. American College of Sports Medicine. (1983). Proper and Improper Weight Loss Programs, Medicine and Science in Sports and Exercise, 15(1), ix-xiii
2. Brownell KD, Steen SN, & Wilmore JH. (1987). Weight regulation practices in athletes: analysis of metabolic and health effects. Medicine and Science in Sports and Exercise, 19(6), 546-556.
3. Burke L, Inge K (1994) Protein requirements for training and ‘bulking up’ (pp 124-150) ). In: Clinical Sports Nutrition Burke L, Deakin V Eds. Sydney: McGraw Hill Book Company
4. Fogelholm GM. (1994). Effects of Bodyweight Reduction on Sports Performance. Sports Medicine, 18(4), 249-267.
5. Greenleaf JE. (1992). Problem: thirst, drinking behaviour, and involuntary dehydration, Medicine and Science in Sports and Exercise, 24(6), 645-656
6. McCargar LJ; Simmons D; Craton N; Taunton JE; Birmingham C (1993). Physiological effects of weight cycling in female lightweight rowers, Canadian Journal of Applied Physiology, 18(3), 291-303
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