Vitamins 'may undo exercise boost'

"Taking vitamins C and E after a workout appears to prevent physical exercise improving the body's energy regulation, a study found. Some vitamins can block this beneficial effect of exercise, the new findings published in the journal Proceedings of the National Academy of Sciences suggest. Exercise is known to increase sensitivity to the hormone insulin, which governs the way cells use sugar as an energy source. Type 2 diabetes occurs when the body becomes resistant and less sensitive to insulin. Ironically, it is the supplements' health-boosting properties that appear to be to blame" - Yahoo