Essentials of Nutrition for Sports

Adaptogens

Adaptogens are “food-grade herbal substances.” At first blush,

herbs sound like a good idea to some consumers. As we have seen in the discussions on pages

143

,^150

, and

152

, herbs can be

problematic.

PacificHealth Laboratories previously used the adaptogen

ciwujia, which sounds more exotic

, perhaps, than its more common

name: Siberian ginseng. PacificHealth Laboratories has claimed that ciwujia: •^

Speeds recovery

-^

Adds stamina and endurance

-^

Decreases lactic acid buildup

-^

Promotes energy use from fat rather than from carbohydrate

-^

Boosts immune system

What evidence do the promoters of this substance offer? The

published literature they quote is in Chinese. They offer no human research published in US or European scientific journals. The studies are not blinded nor controlled.

Some of the studies are in animals. In one human study, the subjects are not athletes; they exercised

only at moderate intensity. The longest exercise bout lasted 60 minutes.

After the Endurox R4 product was promoted, Cheuvront,

Moffatt, et al; of Florida State University performed a double-blind crossover, placebo, random study of 10 subjects who consumed the recommended dosage of Ciwujia for 7 days. The subjects performed cycle ergometry. Their conclusion: The evidence did not support the advertised claims of reduced perceived exertion, reduced lactate production, and faster heart rate recovery.

Also after the Endurox R4 product was promoted, Dustman et al

of Northern Illinois University performed a double-blind, random study of 10 subjects examining their physiological response to stair-stepping. Their conclusion: The evidence did not support advertised claims of increased fat metabolism, decreased lactate accumulation, faster heart rate recovery, or f

eelings of reduced fatigue during

exercise.

PacificHealth Laboratories no longer formulates Endurox with

ciwujia—it is banned by the NCAA. Antioxidants

The claim: The addition of antioxidants (vitamins C and E, beta-

carotene) reduces free radicals associated with exercise and therefore results in improved performance. Antioxidants may help prevent free-radical induced oxidative damage and prevent cancer.

Exercise does result in free-radical formation. Although some changes in blood tests of immune function have

been shown to follow antioxidant supplementation, it is a giant leap to conclude that this will improve

function at cellular level, reduce

cancer, or improve performance.

Studies to date are unconvincing of any role for antioxidant

supplements in recovery products.

Antioxidants are not harmless. As discussed in the basic science

section, beta-carotene antioxidants are associated with cancer and the addition of such supplements has been quietly withdrawn from many products.

For a fuller discussion about the

antioxidants, read the basic

science about vitamin A, beta-carotene, vitamin C, and vitamin E in the free

supplement to this book available at:

http://roadbikerider.com/nutritionforsportssupplement.htm

.

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