Monday, December 21, 2009

Proper Nutrition for Athletes: The Missing Link

Proper Nutrition for Athletes: The Missing Link
By Nancy Clark
From J Exerc Sci Fit, Vol 6, No 2, 130–134, 2008
Nutrition should be an integral part of an athlete’s training program. Yet, in the United States, American athletes and fitness exercisers alike commonly report that they do not eat as well as they should; they admit that nutrition is their missing link. Consequently, they may fail to attain the most benefits from their training programs and their competitive efforts.

The purpose of this paper is to highlight the sports nutrition errors commonly made by American athletes who live in a culture where food is considered “fattening”, eating-on-the-run is the norm, and fast foods are a common alternative to home-cooked meals. Given the rapidly changing food culture in China, this information may help Chinese athletes avoid making the same nutritional mistakes.

Missing Link #1: Respect for the Power of a Proper Sports Diet

“Too many athletes show up for training but they don’t show up for meals. They might as well not show up for training.” These words, spoken by a successful collegiate ice hockey coach, are true indeed. Instead of rushing to training sessions and competitions only to show up poorly fueled, busy athletes would be better off taking a few minutes from their training time to fuel properly and be able to perform better.

Solution: Educate and repeatedly remind athletes about the benefits associated with optimal fueling pat- terns, so they understand that eating a proper sports diet will help them reach their performance goals.

Missing Link #2: Sufficient Calories During the Active Part of the Day

The same athletes who show up underfueled for training are generally the ones who undereat nourishing meals during the daytime, only to overeat sweets and treats with little nutritional value in the evening. This pattern fails to support an optimal sports diet and long-term health. Two reasons why athletes undereat during the active part of their day include:
(1) They are “too busy” to eat. Wrong. If they can find time to train, they can also find time to fuel for training.
(2) They want to lose undesired body fat.

To do so, they restrict their calorie intake at breakfast and lunch. Given that the vast majority of female athletes wants to lose about 2.5kg (5lb), calorie restriction is com- mon. In a survey of 425 female collegiate athletes, 43% of the women reported feeling terrified of be- coming overweight, and 22% were extremely preoccupied with food and weight (Beals & Manore 2000). This fear that “food is fattening” certainly deters many weight-conscious athletes from eating optimally.

Solution: Weight-conscious athletes should pay attention to when they eat. The best time to eat is during the active part of the day, so they will have the energy needed to exercise hard. Increased daytime calories reduces the evening appetite, and this can help weight- conscious athletes consume 10–20% fewer calories at the end of the day. They end up losing weight when they are sleeping, instead of when they are trying to train hard.

Missing Link #3: Equal-sized and Regularly Scheduled Meals

Too many American athletes eat in a crescendo, with the biggest meal in the evening. The better plan is to divide their calories evenly throughout the day, eating every 4 hours, so the athletes are always in the process of fueling-up or refueling.

Solution: A sports dietitian can help athletes create a food plan for a balanced sports diet with the appro- priate amount of calories at each meal. For example, a 2400-calorie fueling plan for an active woman (or a dieting man) who trains after work might look like this:

The first three meals provide the energy needed for a strong workout. The last meal provides the nutrients needed to recover from the workout.

Missing Link #4: Beneficial Amount of Dietary Fat

Some athletes eat too much (>35%) of calories from fat, such as butter, oil, salad dressing and fried foods. The fat displaces the carbohydrates needed to optimally fuel muscles and replenish depleted glycogen stores. The athlete who eats a plate filled with fried chicken for dinner is not carbohydrate-loading on rice, potato or pasta! His performance can suffer due to glycogen-depleted muscles.

Other athletes eat too little fat (<20%of>

Missing Link #5: Pre-exercise Fuel

Athletes who believe they have “no time” to eat before their workout need to think again. Eating 100–300 calories of a pre-exercise snack even 5 minutes prior to exercise enhances performance, assuming that:
(1) the athletes will be exercising at a pace they can maintain for more than 30 minutes and
(2) they can tolerate pre-exercise food. In one study, the subjects ate dinner and then the next morning exercised to exhaustion. They were able to exercise for only 109 minutes with no breakfast, but for 136 minutes with 400 calories of breakfast. That’s a 20% improvement (Schabort et al 1999)!

In another study, athletes biked hard for 45 minutes, and then sprinted as hard as they could for 15 minutes. When they ate a 180- or 270-calorie snack just 5 minutes before they exercised, they improved 10% in the last 15 minutes. They improved 20%when they had first eaten a meal 4 hours prior to the exercise, and then enjoyed the snack 5 minutes pre-exercise (Neufer et al. 1987). That is a significant improvement!

Another study looked at the importance of pre- exercise water and carbohydrates for exercise that lasted less than an hour. The athletes ate no breakfast, biked hard for 50 minutes and then sprinted for 10 minutes to the finish. They were able to: sprint 6%harder when they consumed adequate water versus minimal water; sprint 6%harder with adequate carbohydrates versus no carbohydrates and minimal water; and sprint 12%harder with a sports drink (adequate carbohydrates plus water) (Below et al. 1995). Fueling appropriately certainly enhances performance!

Solution: Athletes need to train their intestinal tracts to be able to tolerate pre-exercise food. They also need to plan their sports diet to accommodate their training. For example: athletes who exercise in the morning can plan to eat part of their breakfast (such as a banana) before the workout, and then afterwards refuel with the rest of their breakfast (such as a bagel and a yogurt); athletes who exercise at lunch could eat part of their lunch (half a sandwich) before the workout and then enjoy the rest of the lunch afterwards; for afternoon or after work sessions, athletes could eat a granola bar or some pretzels pre-exercise, and then refuel with chocolate milk.

Missing Link #6: Optimal Protein Intake

Some athletes eat too much protein (>2g/kg); others eat too little (<>
This amount of protein equates to more than 2.5 g protein per kilogram, and is excessive to the point some of the protein could be wisely traded for more carbohy- drates to better fuel the workouts. In comparison, a vegetarian athlete on a reducing diet could easily consume too little protein as a consequence of restricting food intake. A typical reducing diet might include these protein portions:
Too little protein contributes to poor recovery, muscle wasting, and suboptimal results from hard training. Solution: Athletes who have high or low protein intakes, or who are vegetarian, should consult with a sports dietitian. That nutrition professional can both assess the athlete’s personal protein requirements and teach the athlete how to translate grams of protein into an effective sports diet.
Missing Link #7: Iron to Prevent Fatigue from Anemia
Iron-deficiency anemia is common, particularly in females. Anemia causes needless fatigue and reduced performance. A survey of collegiate athletes found that 20%of female volleyball and basketball players were anemic, as were 50%of the soccer team. Anemia is particularly common among women who have heavy menstrual blood losses, but eat neither red meat nor iron-enriched breakfast cereal (Eichner 2001).
Solution: The athlete who feels needlessly tired should get a blood test (including serum ferritin) to diagnose iron deficiency anemia. To help prevent anemia, all athletes should strive to eat an iron-rich diet that includes red meat or iron-rich alternatives (dark- meat chicken or turkey, salmon, tuna), and iron-fortified cereals (such as Wheaties, Raisin Bran, Total). Including a source of vitamin C (orange juice, strawberries, broccoli, tomatoes) with each meal enhances iron absorption.
Missing Link #8: Post-exercise Recovery Food
At the end of a hard workout, athletes haven’t finished training until they have refueled! They should not sim- ply rush off to work or school, with “no time to eat” as the excuse. Muscle glycogen synthesis is twice as rapid if carbohydrate is consumed immediately after exercise, as opposed to waiting several hours (Ivy 2001).
Solution: Athletes need to plan ahead so they have recovery foods readily available. Even if time is limited, they should be able to refuel their muscles properly. “No time” is no excuse.
Missing Link #9: Carbohydrates Combined with Protein for Recovery Food
Recovery foods should offer a foundation of carbohydrates with protein as the accompaniment, or approximately 1.2–1.5g carbohydrate/kg body weight/hour and 0.4g protein/kg body weight/hour within the first hour after exhaustive exercise, and repeated doses every hour for 4–5 hours (Berardi et al. 2006; Ivy et al. 2002). Some popular choices for American athletes include yogurt, chocolate milk, cereal with milk, and pasta with meat sauce. Athletes need not buy engineered recovery foods unless they are preferred for convenience.
In a 10-week study of recreational body builders, those who consumed a protein-carbohydrate supple- ment both immediately before and right after the mid- afternoon strength training session gained about 1 kg more muscle and about 3kg more in strength (as measured by bench press), compared to the group who did not eat right before and after strength training (Cribb & Hayes 2006).
Eating for recovery can be initiated before exercise. That is, a pre-exercise yogurt gets digested into amino acids and glucose; those macronutrients are available to be put into use when the athlete stops exercising (Zachwieja 2002).
Athletes who train twice a day definitely need to rapidly refuel with a proper recovery diet. A 6-week study with collegiate swimmers reports that those who did two workouts (morning and afternoon) sprinted slower than those who swam only in the afternoon (Costill et al. 1991). Although no mention was made of diet, the decline in performance may have been related to the inadequate dietary patterns that are common among college students.
Solution: Exhausted athletes may not feel hungry for solid foods after a hard bout of exercise, but they might welcome a fruit smoothie (blenderized fruit with yogurt) or chocolate milk. Both contain carbohydrates to refuel, and protein to build/repair muscles and reduce muscle soreness.
Missing Link #10: Rest Days for Muscles to Refuel
Rest is an important part of a training program; muscles need time to refuel and heal. In one recovery study, subjects ran hard for about 16 kilometers on 3 consecutive days while eating a typical American diet that provided inadequate (50%) carbohydrates. By the third day, the athletes’ glycogen stores were low and the muscles felt tired (Costill et al. 1971). This study points out the importance of eating a carbohydrate-rich diet on a daily basis during periods of hard training, as well as the importance of days with little or no exercise. Depleted muscles may need more than 24 hours to replace glycogen stores.
Although rest days with little or no exercise enhance a training program, athletes who want to lose weight commonly hesitate to take a rest day; they fear they will “get fat”. These athletes need to understand: (1) On a rest day, they may feel just as hungry because the muscles need food to refuel. (2) They will gain (water) weight. For each 1g of glycogen, the muscles store about 3g of water. This water gets released during exercise; it is beneficial.
Solution: Athletes should schedule into their training program 1–2 rest days a week, and observe the benefits: better performance the day after a rest day.
Missing Link #11: Adequate Fluids
Athletes who maintain optimal hydration can train harder and perform better. For each 1%of body weight lost via sweat, the heart has to beat 3–5 more times per minute (Casa et al. 2000); this creates needless fatigue.
Solution: Athletes should be taught to monitor their urine to determine if they are adequately hydrated. Athletes who are well hydrated will need to urinate every 2–4 hours, and their urine will be a light color. Athletes who sweat heavily should learn how much sweat they lose (and thereby need to replace) during strenuous exercise. To learn their sweat rate, they simply need to weigh themselves without clothing before and after exercise. For each kilogram of sweat lost, they should drink at least 1.0–1.5 liters of fluid (American College of Sports Medicine 2007).
Missing Link #12: Sodium Before Exercise in the Heat
Research with trained cyclists reports that they rode 20 minutes longer to exhaustion (99 vs. 79 minutes) in 32°C heat when they drank a pre-ride beverage with 1000mg versus ∼150mg sodium. They consumed no fluids while riding (Sims et al. 2007).
Solution: Athletes who train and compete in the heat should consume salty foods pre-exercise. Sodium holds water in the body and reduces the risk of becoming dehydrated.
Missing Link #13: The Sports Dietitian
Serious athletes generally have a support crew that includes a coach, sports psychologist, medical doctor, physical therapist and massage therapist. But to their detriment, some fail to have a sports dietitian on their team.
Solution: Serious athletes who want to get the most from their training programs should meet with a nutrition professional to get a “nutrition check-up”. In the USA, athletes can use the referral network at to find a local registered dietitian who is a Board Certified Specialist in Sports Dietetics (RD CSSD). This professional can help athletes to resolve struggles with “no time” to eat prop- erly, find solutions to intestinal distress related to pre-exercise food, attain the desired weight and per- cent body fat, and transform disordered eating into effective fueling. Conclusion All athletes can benefit from sports nutrition education that focuses on the benefits associated with consuming a proper sports diet. These benefits include better per- formance, desired body weight/percent fat, and faster recovery. With nutrition education, athletes can learn to make responsible food choices that support the rigors of their training programs and competitive events. Every athlete will always win with good nutrition.
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