The effects of cocoa flavanol supplementation on endothelial function and exercise performance.

Cocoa flavanols have gained attention from beneficial effects on endothelial function and exercise performance, especially in clinical populations. Few studies have utilized healthy college-aged adults. Twenty college-aged males and females completed this randomized, double-blind study. Participants completed 14 days of supplementation with either cocoa flavanols (375 mg) or placebo (0 mg cocoa flavanols). Measurements on flow-mediated dilation (FMD%), resting heart rate, resting blood pressure, and exercise performance (anaerobic and aerobic) were performed pre- and postsupplementation. There were no significant interactions between groups and time or any main effects for dependent variables. Treatment group FMD% tended to increase insignificantly from 16.48 ± 2.69% to 18.24 ± 3.18%, while placebo group decreased insignificantly from 22.70 ± 2.84 to 15.76 ± 3.35, p = .25. Cocoa flavanol supplementation does not appear to significantly improve endothelial function or exercise performance in the population used. Future studies could use larger doses on larger samples.