Essentials of Nutrition for Sports

Target this cause of muscle cramps by eating a diet rich in
carbohydrate, magnesium, potassium, and calcium—a diet good for overall general health as well.

If riding long, hard, or day-after-day in the heat, add sodium to

your diet.

Summary

During exercise, it is all about sodium. Most mineral losses in sweat are unimportant or compensated for

by the increased caloric consumption of athletes.

Calcium and iron may be exceptions. Some athletes may need

calcium or iron supplements for general health.

A daily multivitamin/multimineral

supplement will help provide

the RDA of most minerals. Calcium requires a separate supplement.

Free Radicals

Antioxidants

Exercise may increase free radical formation. Antioxidants,

which interact with free radicals, are promoted to enhance performance and recovery from exercise.

Free radicals are atoms or groups of atoms with an odd

(unpaired) number of electrons.

Free radicals can be formed when oxygen interacts with some

molecules. Once formed, free radicals can react with cellular components, such as DNA, or the cell membrane.

Free radicals arise normally duri

ng metabolism. Environmental

factors such as pollution, radiation, cigarette smoke, and herbicides can also spawn free radicals.

Antioxidants act as scavengers, interacting with free radicals to

prevent cell and tissue damage that could lead to cellular damage—thought to be a common pathway for cancer, aging, and a variety of diseases.

Several enzyme systems within the body scavenge free radicals. The principle antioxidants are vitamin E, beta-carotene, vitamin

C, and selenium. Thiamine, riboflavin, pantothenic acid, vitamin D, vitamin K, copper, magnesium, manganese, molybdenum, and zinc also have antioxidant roles. Read more about these individual antioxidants in their respective chapters.

Preventing Cancer and Heart Disease

Studies show lower cancer rates in people whose diets are rich in

fruits and vegetables. This has lead

to the theory that these diets

contain substances, possibly antioxi

dants, which protect against the

development of cancer.

Nutrition for Sports, Essentials of 25