Vitamin C and the Strength-Power Athlete-Vitamin
Several studies have established that exercise training is associated with a decrease in the accumulation of the products used to assess oxidative stress or an enhancement of antioxidant enzymes.
Although little research has been conducted on the ascorbic acid (vitamin C) needs of strength-power athletes (SPAs),
what we know about the functions of ascorbic acid indicate that SPAs should probably be consuming ascorbic acid at levels above the Recommended Dietary Allowance (RDA). Research clearly shows that deficiency, or even marginal ascorbic acid status, can adversely affect physical performance. For example, muscle weakness is a common symptom of vitamin C deficiency. Vitamin C has several functions that would be important to the performance of SPAs. For example, vitamin C is needed for the integrity and strength of tendons and ligaments. Ascorbic acid also is needed for the synthesis of adrenaline, which is needed to produce the excitatory state before and during performance. Adequate intake of the vitamin causes a lower release of the hormone, cortisol, in response to physical stress. Cortisol is a catabolic hormone that causes the body to break down skeletal muscle. Thus, lower secretion of this hormone may result in better performance. In general, any physical stress could cause an increased need for vitamin C. Finally, ascorbic acid is a powerful water-soluble antioxidant. Research has established that physical training, including weightlifting, causes an increased production of oxidative damage markers. Vitamin C, in its antioxidant capacity, would function to reduce the level of these damage products. Studies do seem to indicate that strenuous physical activity increases the need for vitamin C. Animal and human studies show reduced tissue levels of ascorbic acid with exercise. Reduced urinary excretion of the vitamin following exercise has also been reported. Several studies show better heat adaptation with improved vitamin C status. One study, using junior elite weightlifters, did report a reduced serum cortisol concentration in the lifters following a training session when the lifters had been consuming a vitamin C supplement versus when they consumed a placebo. The Recommended Dietary Allowance for vitamin C is 60 mg/day. However, recent studies in nonathletes suggest that an optimal vitamin C intake is more likely to be around 200 mg/day. Because physical training, such as weightlifting, places stress on the body, optimal vitamin C needs in SPAs may be 200 mg or higher. Vitamin C and exercise studies generally indicate that intakes of various athletes should be in the 200-500 mg/day range. Minimal evidence shows that intake of ascorbic acid above 1000 mg daily is beneficial to a person in general or to athletes specifically. Although vitamin C supplements are inexpensive to purchase and easy to take, many athletes can easily consume 200 mg/day or more in their normal diets. Studies with bodybuilders and football players show normal vitamin C intake to be 180-300 mg/day. A single 8-ounce glass of orange juice will provide approximately 100-120 mg of vitamin C. If the athlete consumes a proper selection of high vitamin C fruits and vegetables, then meeting the 200-500 mg/day intake level should not be a problem. Although ascorbic acid is a nontoxic vitamin, doses above 1 g/day may cause irritation and discomfort to the gastrointestinal system. Again, obtaining the vitamin from proper dietary selection is the best way to proceed.
