THE STUDY Researchers from Aberystwyth University (Wales) had men consume either 100 grams (about 3 1⁄2 ounces) of 70% cocoa dark chocolate or a control bar before pedaling on a stationary cycle for 2 1⁄2 hours at a moderate pace. They measured the subjects’ blood glucose and insulin levels, as well as markers of oxidative stress.
THE RESULTS They reported in a 2011 issue of the European Journal of Nutrition that when the subjects consumed the dark chocolate before the workout they were able to maintain their blood glucose levels, had higher insulin levels and experienced less oxidative stress. The ability to better maintain blood glucose levels means that you’ll have more energy to keep up your training intensity. The higher insulin levels can help to better drive muscle growth. However, higher insulin levels during a workout can limit fat burning. So if your major goal is fat loss, add the chocolate to your post-workout shake instead. The lower oxidative stress means enhanced muscle recovery after the workout, which can lead to greater growth.
THE DOSAGE Add 3–4 oz of dark chocolate that is at least 70% cocoa or add 1⁄4 cup cocoa powder to your preworkout or postworkout shake.
REFERENCE: G. Davison et al., “The effect of acute pre-exercise dark chocolate consumption on plasma antioxidant status, oxidative stress and immunoendocrine responses to prolonged exercise,” European Journal of Nutrition, in press, 2011.