Spinach May Enhance Performance. Or Not.

Popeye may have been right: eating spinach and other leafy greens that are high in nitrates could improve athletic performance. Or not.  Science Daily reports on research conducted at the University of Leuven in Belgium, where  27 “moderately trained” athletes were given nitrate supplements before  Sprint Interval Training (SIT), — short but intense cycling sessions three times a week. The study, which included workouts in normal oxygen conditions and in hypoxia conditions, which are low oxygen levels such as those found in high altitudes, showed that after only five weeks, the muscle fiber composition changed with the enhanced nitrate intake when training in low oxygen conditions. The conclusion, kind of, is this: Enhancing these muscle fiber types through nutritional intake could very well boost the performance in this type of events. Sounds promising, but the researchers warn that it’s not yet clear that increasing fast-oxidative muscle fibers actually improves performance. Also, warns one researcher: “consistent nitrate intake in conjunction with training must not be recommended until the safety of chronic high-dose nitrate intake in humans has been clearly demonstrated.”