Food Power for Athletes

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B
oth competitive and recreational athletes are often in maintaining the tissues of the body. Overall, a high-carbohy-
search of a nutrition program to provide that winning drate diet is most important in ensuring optimal storage of
edge. Many individuals are prone to experiment with vita- carbohydrate in the body, fueling the body for exercise, and sup-
mins and other supplements, protein powders, and pills, at the porting performance in both the endurance6 and strength ath-
cost of a simple, yet important, performance factor—diet. While lete.7,8 A vegetarian diet, which emphasizes whole grains, fruits,
genetic, physical, and psychological factors all play important vegetables, and legumes, provides the high carbohydrate content
roles in determining athletic abilities, poor eating habits and nutri- to fuel your body through training sessions and competition.
tional deficiencies can impair performance. An appropriate sports
diet will help support both athletic training and competition. Power for Protein

The Nutrition Game Plan

S trength and endurance athletes both have increased protein
needs.1 Protein, composed of chains of molecules called

D ue to the heavy demands of exercise and physical activity,

athletes need extra nutrition. There are three basic fuels
the body relies on while exercising—carbohydrate, fat, and pro-
amino acids, plays an important role in the building, mainte-
nance, and repair of the tissues of the body, including muscle.
There are 20 different amino acids in the foods we eat, but our
tein—and more calories from these fuels are required to sus- body can make only 11 of them. The 9 essential amino acids
tain energy levels and maintain lean body mass.1 In particular, which cannot be produced by the body must be obtained from
a balanced diet that is high in carbohydrate, low in fat, and the diet. A diet based on a variety of grains, legumes, and
adequate in protein, is the recommended diet for athletes.1,2 vegetables easily provides all of the essential amino acids. It was
Due to its high carbohydrate and low fat content, a vegetarian once thought that various plant foods had to be eaten together
diet is an optimal sports diet.3 It is also rich in vitamins, miner- to get their full protein value, a method known as “protein
als, and antioxidants—important nutrients that help the body combining” or “complementing.” We now know that inten-
utilize energy and protect it from the stress of exercise. tional combining is not necessary to obtain all of the essential
amino acids.9 Concentrated protein sources include tofu,
Fueling Your Body: Carbohydrate Gets the Gold soymilk, tempeh, seitan, and various meat analogues which
can be purchased in any health food store or the vegetarian

Y our body is always burning a mixture of carbohydrate, fat,

and protein. The duration of exercise, intensity of exercise,
level of physical conditioning, and initial muscle glycogen levels will
section of your grocery store.
Protein requirements are very individualized and are pri-
marily dependent upon body size. The Recommended Dietary
determine which primary fuel your body will use.4 In general, Allowance (RDA) for the average, sedentary or lightly active
carbohydrate is the primary fuel utilized during high intensity ex- adult is 0.8 grams per kilogram of body weight per day.10 For
ercise. In fact, about 55 to 75 percent of calories in the diet should most people, this is more than enough. However, some au-
come from carbohydrate, and even more in individuals who thorities believe that protein needs for athletes may range from
compete in endurance or ultra-endurance events.1 Whole grains, 1.2 to 1.7 grams per kilogram of body weight per day for the
fruits, and vegetables are excellent sources of carbohydrate. highly active adult athlete.5,11 Tips for meeting your protein
With prolonged exercise, at lower intensities, fat (in the needs are included in the table below.
form of fatty acids) becomes the primary fuel source. The It is important to keep in mind that while some protein will
shift to fatty acids during exercise helps spare the carbohy- be broken down into amino acids for fuel during exercise, the
drate (glycogen) stores in your body and allows for pro- primary role of protein is for structure and support. While pro-
longed exercise. However, while high carbohydrate intake is tein needs are increased in the diet of athletes, adequate (10 to 15
recommended for performance, there is no need to increase percent of calories or enough to meet your calculated require-
fat in the diet beyond the commonly recommended 10 to 30 ments), but not excess, protein should be consumed. Protein
percent of calories, as it is taken from storage sites in the should come from plant sources, rather than meat, dairy prod-
muscles when needed. Increasing fat in the diet is not recom- ucts, and eggs, which are devoid of fiber and complex carbohy-
mended for improving performance.5 drates. Emphasis should be placed on a diet that is high carbohy-
Compared to carbohydrate and fat, protein is used only mini- drate to ensure that protein is spared for those activities it does
mally for fuel,4 as its primary function is for building and best: the building and repairing of body tissues, including muscle.

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 Tips for Meeting Protein Needs diet for both performance and health. By choosing generous
servings of these foods with a focus on variety and wholesome-
• Top salads with a variety of beans, including chick ness, your body will reap the benefits.
peas, kidney beans, great northern beans, and black
beans. These legumes have as much as 7 to 10 grams • Whole grains: Choose whole wheat or enriched breads, cere-
of protein per serving. als, rice, and pastas. They are rich in complex carbohydrate,
• Shake it up! Blend non-dairy frozen desserts or soft fiber, zinc, and B vitamins. A single serving also provides
tofu with your favorite fresh or frozen fruits with about 2 to 3 grams of protein.
soy or rice milk for a thick, delicious, creamy, high- • Vegetables: Choose a variety of colorful red, orange, and yel-
protein shake. low vegetables in addition to leafy greens for vitamin C, beta-
• Marinated tempeh or veggie burgers, grilled on a carotene, and other antioxidants that will protect your body
bun or added to pasta sauce, offer a quick protein from the stress of exercise. These foods also provide iron,
boost to any meal. calcium, fiber, and a modest 2 grams of protein per serving.
• On the go? Sports bars and soy powder shakes are • Legumes: Choose a variety of beans (chickpeas, black beans,
quick and convenient supplements that can help kidney beans, great northern beans) as well as soymilk, tofu,
increase the protein content of any well-balanced tempeh, and textured vegetable protein. They are not only
vegetarian diet. high in protein (about 7 to 10 grams per serving), but also rich
in complex carbohydrate, fiber, iron, calcium, and B vitamins.
Staying Hydrated • Fruits: Choose a variety of fruits and fruit juices for extra
vitamins, especially vitamin C.

M aintaining optimal hydration status is important in pro-

moting peak performance and preventing injury. Dehy-
dration, defined as body weight loss of 1 percent or more due
• Vitamin B12 supplement: A multivitamin/mineral supple-
ment or vitamin B12 supplement can be taken daily or every
other day to cover nutritional needs. Fortified foods, such as
to fluid loss, results in a number of symptoms including head- Kellogg’s Cornflakes, Product 19, and Total Cereal, or forti-
ache, fatigue, heat intolerance, and dark urine with a strong fied soy and rice milks, may also contain the active form of
odor. More serious effects include heat cramps, heat exhaus- vitamin B12, cyanocobalamin.
tion, and heat stroke.12 By maintaining a regular fluid schedule
of at least eight 8-ounce glasses of water per day, these symp- References
toms are easily prevented.12 1. Position of the American Dietetic Association and the Canadian
Fluid needs increase with exercise. Additionally, participat- Dietetic Association: nutrition for physical fitness and athletic per-
ing in activity at high altitudes, low humidity, and high tem- formance for adults. J Am Diet Assoc 1993;93:691.
peratures can also increase fluid needs.12 The following guide- 2. Houtkooper L. Food selection for endurance sports. Med Sci Sports
Exerc 1992;24(9suppl):S349-59.
lines, endorsed by the American College of Sports Medicine,
3. Nieman DC. Vegetarian dietary practices and endurance perfor-
can help you stay hydrated:13 mance. Am J Clin Nutr 1988;48(3suppl):754-61.
4. Liebman M, Wilkinson JG. Carbohydrate Metabolism and Exercise.
• Two hours before exercise: Drink 17 ounces (or about 2 In: Nutrition in Exercise and Sport, 2nd ed. Wolinsky I and JF Hickson,
cups) of fluid. eds. CRC Press: London,1994.
• During exercise: Drink 4 to 8 ounces (or about 1/2 to 1 cup) 5. Williams C. Macronutrients and performance. J Sports Sci 1995;13:S1-10.
of fluid every 15 to 20 minutes. 6. Jacobs KA, Sherman WM. The efficacy of carbohydrate supplemen-
tation and chronic high-carbohydrate diets for improving endur-
• After exercise: Drink 16 to 20 ounces (or about 2 to 2½
ance performance. Int J Sport Nutr 1999;9(1):92-115.
cups) of fluid for every pound lost during exercise; weighing 7. Haff GG, Stone MH, Warren BJ, et al. The effect of carbohydrate
yourself before and after exercise can help you determine supplementation on multiple sessions and bouts of resistance exer-
your fluid loss. cise. J Strength Cond Res 1999;13(2):111-7.
8. Leveritt M, Abernethy PJ. Effects of carbohydrate restriction on
Water is ideal as a fluid replacer, particularly for activities last- strength performance. J Strength Cond Res 1999;13(1):52-7.
ing less than one hour. For those activities lasting more than 60 9. Position of the American Dietetic Association: vegetarian diets. J
Amer Diet Assoc 1997;97(11):1317-21.
to 90 minutes, sports drinks containing carbohydrate or elec-
10. Food and Nutrition Board. Recommended Dietary Allowances, 10th
trolytes may be useful both during and following exercise.13,14 ed. National Academy Press: Washington, DC,1989.
Electrolytes and carbohydrate can also be easily ingested through 11. Lemon PW. Do athletes need more dietary protein? Int J Sport Nutr
food, in addition to water, following a training session or event. 1995;5(suppl):S39-61.
12. Kleiner SM. Water: an essential but overlooked nutrient. J Amer Diet
Ready, Set, Go! Assoc 1999;99:200-6.
13. Convertino VA, Armstrong LE, Coyle EF, et al. American College of
Sports Medicine position stand. Exercise and fluid replacement.

T he sports diet must be as carefully planned as the training

regimen. A well-balanced vegetarian diet, emphasizing con-
sumption of a variety of foods from the new four food groups—
Med Sci Sports Exerc 1996;28:i-vii.
14. Puhl SM, Buskirk ER. Nutrient Beverages for Exercise and Sport. In:
Nutrition in Exercise and Sport, 2nd ed. Wolinsky I and JF Hickson,
grains, legumes, fruits, and vegetables—is an optimal sports eds. CRC Press: London, 1994.

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