New research is suggesting that women who take vitamin C before performing half an hour of moderate intensity cycling showed increased antioxidant capacity post exercise.
Vitamin C increases the antioxidant power of the blood
Ingesting Vitamin C (also known as ascorbic acid) before exercises increases the antioxidant power of the blood and appears to lessen exercise induced oxidative stress in the body.
The researches, from Chiang Mai University in Thailand, looked at a marker of stress in the body called superoxide dismutase - they found that it's activity was elevated after exercise when paired with a placebo pill. But when exercise was paired with ascorbic acid, activity of the stress marker was suppressed.
Vitamin C is a powerful antioxidant, as has already been well established, however the efficacy of vitamin C supplementation
on exercise-induced oxidative stress remains unclear. The objective of this latest study was two-fold, firstly it was to see if ascorbic acid supplementation would support antioxidant defenses and glucose metabolism and secondly if it would prevent muscle damage after a single bout of exercise by an untrained healthy adult. Regarding the second objective, no link was found. They wrote:
"Supplementation with ascorbic acid prior to exercise improves antioxidant power by does not prevent muscle damage."
The study, published in the Journal of the International Society of Sports Nutrition, looked at 19 healthy women between 22 and 25 years of age. They were sedentary in lifestyle and had not participated in any regular exercise program for at least a year. Blood tests were used before and 30 minutes after exercise to determine oxidative stress and muscle damage markers.
The participants performed the exercise in a fasted stated which means that it's difficult to extrapolate the results to conditions where athletes do not fast before exercise, a clear limitation of the study.