Vitamins, specifically the anti-oxidants vitamins C and E, may do harm than good, at least to those who workout regularly. Gretchen Reynolds reports in the New York Times on research conducted at the Norwegian School of Sport Sciences that divided 54 healthy adult men and women into two groups, one of which took four pills a day with 1,000 milligrams of vitamin C and 235 milligrams of vitamin E, and one of which got placebo pills. All participants undertook a tough 11-week training program, which included interval training and hour-long runs. When it was done, everyone’s fitness had improved, with maximum endurance capacity increasing about 8 percent, but some indications of fitness differed between the two groups. Reynolds reports that those in the placebo group saw big gains in biochemical markers that bolster the creation of mitochondria, which generate energy in muscles. “The creation of new mitochondria” she writes, “is generally held to be one of the most important effects of exercise.” And now the bad and somewhat surprising news: those in the group given antioxidants had significantly lower levels of the markers related to mitochondrial creation. Read more in the New York Times.