Note: The following information is not intended as a substitute for appropriate physician, and nutritionist guidance.
No caffinated beverages for players. (Note that caffeine is a restricted substance per the International Olympic Committee.)
The rule of thumb for eating before
exercise is to allow 4 hours for a big meal (about 1,200 calories), 2
hours for a light meal (about 600 calories), and an hour or less for a
snack (about 300 calories). Sample carbohydrate-rich menus:
|Large Meal||Light Meal||Snack|
|2 large bagels||2 c spaghetti||1 medium banana|
|2 tbsp peanut butter||1/2 c tomato sauce||1 pkg instant oatmeal|
|2 tbsp jam||8 oz low-fat milk||8 oz low-fat milk|
|8 oz fruit yogurt|
|16 oz orange juice|
During Game Nutrition:
So you won't go hungry if you're traveling to a game, stash 1,000 calories of tried-and-true food in your bag. (Never try new foods before an important event.) You might even pack extra snacks for underfed teammates. On game day you can add perishable items such as yogurt, bagels, apples or other fresh fruit, or even a sandwich or two. Some possibilities:
Candy? Research suggests that candy doesn't hurt most people's sports performance. In one study, reported in the March 1987 Journal of Applied Physiology, athletes who ate a big breakfast 4 hours before and a candy bar 5 minutes before hard exercise improved 20% during the exercise test compared with when they ate nothing. The results of the study also suggest that just candy and no breakfast before exercise improved performance 10% in comparison with eating nothing. Snickers Bars are a good choice.
Some people are sensitive to pre-exercise sugar, however, and have a rebound blood-sugar low that makes them feel weak. Hence, the safest bet is to eat the candy within 5 to 10 minutes of starting activity. This span is too short for the body to respond. (Or, eat the candy more than 45 minutes before exercise to allow insulin levels to drop.)
Candy is better than nothing, but it's not premium fuel. It's better to eat a more wholesome snack like cereal, a banana or apple, yogurt, or pretzels and juice. The urge for a quick energy fix is a sign you've eaten too little food earlier in the day. To prevent cravings, eat a hearty breakfast and lunch.
Energy Bar Comparison Chart:
(You should drink at least 8 to 16 ounces of water with an Energy Bar)
Perspiration and exertion deplete the body of fluids necessary for an optimal performance and lead to dehydration and hyperthermia (over heating). It is important to drink plenty of cool water, at least a half a cup of water every 20 minutes of exercise. Adding a teaspoon of sugar, a little fruit juice or a small amount of powdered drink mix flavors plain water and may encourage fluid intake.
For the calorie conscious: A teaspoon of sugar, has only 15 calories* per teaspoon. *Note: Like all carbohydrates, sugar really has 4 calories per gram, and there are 4 grams to a teaspoon. The FDA's 1993 food labeling regulations require rounding to 15 calories on consumer packages.
Usually there is no need to worry about replacing carbohydrates unless the exercise lasts over 90 minutes and is hard and continuous. When this happens, drinking a sports drink or other beverage with some sugar in it will fuel and water to the muscles being exercised.
Make a homemade sports drink by mixing no more than 4 teaspoon of sugar, 1/4 teaspoon of salt and some flavoring (like a teaspoon of lemon juice) in 8 ounces of water.
The main benefit sports drinks provide is hydration, which is why water is their most important component. Dehydration both decreases performance and is potentially life-threatening. Regular water intake is essential during exercise.
The second ingredient sports drinks contribute is carbohydrates, usually in the form of sugars (glucose, fructose, and sucrose) or short-chain starches (maltodextrins). Muscles use carbohydrates as their fuel of preference, and carbohydrates in sports drinks help replace carbohydrates that are burned during exercise. During prolonged exercise bouts (90 minutes and longer), sports drinks do a better job than plain water in delaying fatigue and prolonging endurance. Research has shown that mixtures of the previously mentioned carbohydrates are more quickly absorbed than a single sugar, and that the total concentration of carbohydrates should not exceed 8% (that equals about 19 grams or 75 calories of carbohydrates per 8 ounces) for optimal absorption rate.
The next most important component of sports drinks is the electrolyte mineral sodium, which actually plays several important roles in sports drinks. Sodium enhances fluid absorption in the gut (this is aided by glucose in the drink), helps to maintain plasma volume, replaces sodium lost in sweat, improves the palatability of the drink (which increases intake), and stimulates the thirst mechanism (which also increases intake). Although other minerals are also lost in sweat (such as potassium), the amounts lost are so small that their presence is not necessary in sports drinks, and their levels can be replaced after exercise with a normal diet.
Sports drinks also contain coloring and flavoring agents and often a little citric acid to add tartness to the taste. These enhance palatability, which means we'll drink more. That's really more important than it seems, because the best sports drink is no good unless it gets inside the athlete.
One more item deserves mention: drink sports beverages cold; fluids that are about 40 degrees F. are better absorbed than warm fluids.
High-carbohydrate drinks are designed for post-exercise carbohydrate replacement -- after you've already worked on rehydrating with a sports drink. Virtually any high-carbohydrate source works well: soft drinks, juices, solid foods, etc., so there's no reason to limit ourselves to the high-carbohydrate sports drinks.
As for protein drinks and powders, these are the oldest and stalest player in the sports nutrition world. Consuming more dietary protein does not equal more muscle protein. Actually, endurance athletes have more of a need for dietary protein than weight lifters, but the truth is that dietary protein is virtually never the limiting factor for muscle growth and recovery in American athletes (that is folks who eat a Western-world type diet). High protein products tend to be a waste of money, but they aren't likely to physically harm us.
- One of the main sources of energy for working muscles
- 60-70% of your calories should come from carbohydrates
Foods to be eaten before exercise:
|Low Carbohydrate foods||Moderate Carbohydrate foods||High Carbohydrate foods|
Spaghetti (no sauce)
Apple juice, unsweetened
Grape nuts cereal
|Protein 15-20% of your calories should be from lean protein sources|
|Good sources of protein:|
Avoid saturated fats such as:
the high fat foods such as:
Other low fat choices:
|Be sure to limit fried and high-fat foods like burgers, fried chicken, french fries, and nachos. These and similar fast foods take a long time to digest.|
Energy-Nutrient Intake Distribution
Ideal distribution of carbohydrate, protein, and fat for athletes is similar to recommendations in the Dietary Guidelines for Americans and the Canadian Nutrition Recommendations.
In general, it is recommended that 60% to 65% of total energy should come from carbohydrate. A threshold of 500 to 800 g (2,000 to 3,200 kcal) carbohydrate per day, regardless of the total daily energy intake, may be necessary to maintain maximal muscle glycogen stores in athletes. Maximizing muscle glycogen stores provides greater energy reserve for aerobic and anaerobic activities, resulting in greater endurance and delayed fatigue.
Athletes may require more protein than the Recommended Dietary Allowance (RDA) of 0.8 g/kg body weight. Recent data confirm the protein-sparing effect of carbohydrate. In addition, research suggests that the quantity of dietary protein needed to achieve maximal protein deposition is 1.5 g/kg body weight, and that the limiting factor for muscle protein deposition is energy intake, not protein. Therefore, athletes who wish to increase muscle mass should meet their energy requirements first, through an adequate intake of carbohydrate, and then check that they have met their protein needs.
Protein needs can be calculated both as a percentage of total energy and on a per kilogram body weight basis. For athletes with exceptionally high energy intakes, providing 12% to 15% of total energy from protein may be excessive. When energy intake is low, as typically observed for many young women or low body weight athletes, protein needs calculated as a percentage of energy may be inadequate. In both of these cases, 1.0 to 1.5 g protein per kilogram body weight may be a more appropriate guide for intake than protein as a percent of total energy.
Fat should contribute no more than 30% of total energy to the diet. Energy needs above this level should be derived from high-carbohydrate/low-fat food sources.
Vitamins and Minerals
Vitamins and minerals play an important role in the metabolism of protein, carbohydrate, and lipids and in muscle function. Although physical activity increases the need for some vitamins and minerals, this increased requirement typically can be met by consuming a balanced high-carbohydrate, moderate-protein, low-fat diet. Individuals at risk for low vitamin/mineral intake are those who consume a low-calorie diet.
Iron and calcium are two minerals of concern, especially for young athletes and women of all ages involved in physical activity. Iron, as a component of hemoglobin and myoglobin, is essential for oxidative metabolism to occur. Diets that provide little or no meat limit the most available dietary sources of iron.
Osteoporosis is a major health concern for women in North America and is related to calcium intake, estrogen level, alcohol and caffeine intake, family history, and the amount and type of physical activity. The emphasis for prevention of osteoporosis should be to maximize the body's stores of calcium early in life, maintain that level, and minimize any loss. A calcium intake of 800 to 1,200 mg/day is recommended to protect against the development of osteoporosis.
Achieving this recommended daily intake, in conjunction with performing regular weight-bearing activities, will promote the deposition of calcium in bone and thereby reduce the risk of developing osteoporosis. Nutrition guidance should be given to low-body-weight, amenorrheic women who appear to be at high risk of early osteoporosis.
Increased muscular activity leads to an increase in heat production in the body; this is dissipated, in part, through the production of sweat. To prevent dehydration, water must be replaced at a faster rate. Dehydration has an adverse effect on muscle strength, endurance, and coordination and increases the risk of cramps, heat exhaustion, and life-threatening heat stroke.
Dietary considerations for young athletes who exercise regularly differ only in the need for special attention to energy requirements. Adequate caloric intake is important to achieve optimal growth velocities and maintain health status.
Young people have a greater surface area and lower sweating capacity than adults and, as a result, are more susceptible to hyperthermia (over heating) than are adults. This problem is exacerbated by the fact that young people produce more heat per unit body weight than adults and are less capable of transferring this heat from the muscles to the skin. The differences in thermoregulation between young people and adults strongly suggest that they should not be exposed to the same exercise intensities as adults, regardless of environmental conditions. In addition, they appear to be more prone to overuse injuries. Any exercise training program that is initiated by a young person should progress slowly, allowing ample time for acclimatization, conditioning, and skill development to improve athletic performance.
Young athletes require accurate information on establishing safe weight and body composition goals. Studies suggest that some adolescent athletes, particularly women, consume diets that are low in energy and nutrients. The combination of high nutrient and energy requirements necessary to support growth and training and dietary self-restriction justifies monitoring these weight-conscious athletes for signs of dietary deficiencies and related health problems. These athletes should be provided with information regarding healthful food choices, meal planning, the role of snacks, finding time for eating, and realistic goal setting.
|Our thanks to the
following websites and individuals for contributing to the
information contained here.
Last updated 03/11/2004