Facts on Nutrition and Exercise

Overview

Exercise burns calories, breaks down muscle and depletes stored energy. We need food and fluids to replace what is lost through exercise so that our bodies can repair themselves and come back stronger. Since the food that you eat eventually becomes a part of your tissues, nutritional quality is paramount. Athletes don't need to eat massive quantities of food if they eat a wholesome, varied diet made up of nutrient-dense foods.

Carbohydrates

Starches, fruits and vegetables all derive most of their calories from carbohydrates. The media have demonized "carbs," but your body needs carbohydrates to function properly; and athletes' carbohydrate needs are even higher. Your body breaks carbohydrates down into glucose, which is stored in your muscles. When you exercise, glucose is released back into your bloodstream for energy. Carbohydrate stores are finite and must be replaced. A percentage of the calories you burn during exercise come from fat, but you need carbohydrate to metabolize that fat.

Protein

Exercise damages muscles. This is a good thing because your body then rebuilds muscles stronger than before. Your body uses amino acids derived from protein to rebuild muscle tissue. To get the eight amino acids that their bodies can't synthesize, athletes should eat high-protein foods like meat, eggs, nuts, seeds and legumes. Massive amounts of protein won't turn into muscle, making an athlete "bulk up." Your body can only absorb one gram of protein per pound of body weight. After you meet protein requirements, the rest is eliminated as waste or stored as fat.

Fats

Not all dietary fat is stored as body fat. Our bodies need fat to build healthy cells and as a source of energy. Avoid disease-promoting saturated and hydrogenated fats. Monounsaturated and polyunsaturated fats (the key part being "unsaturated") are healthy and contain antioxidants. Also, a study by Jaya et al (2001) found that consuming more dietary fat increases the time that trained runners can run before exhaustion.

Vitamins and Minerals

There are 28 vitamins and minerals that your body needs to stay healthy. A healthy and varied diet full of nutrient-rich foods easily meets all these requirements without supplements. Modern nutritional science doesn't fully understand how vitamins and minerals work together within foods, and there may be factors that we still haven't discovered. It's safe to take a multivitamin as "insurance," but aim to get your recommended daily allowance of vitamins and minerals through food.

Hydration

Your body needs water to work properly. A 2 percent loss of body weight from dehydration can lead to a 10 percent decline in performance. To make sure that you are getting enough water, drink eight cups of water a day. In addition to those eight cups, athletes must replace water lost through perspiration. As a rule of thumb, your urine should be clear. If urine is dark yellow, you should drink more fluids. Electrolytes are a lesser-known aspect of hydration, but no less important. Electrolyte levels must be balanced for neurological pathways to work properly. Electrolytes are lost through sweat, so drink sports drink during extended periods of heavy sweating.