An article published in the Japanese journal, Nutrition:
“Flavanol-rich cocoa consumption enhances exercise-induced executive function improvements in humans,” by Hayato Tsukamoto (et al.), DOI: http://dx.doi.org/10.1016/j.nut.2017.08.017/, conducted a test of the health benefits of high-dose cocoa, versus low-dose cocoa, with exercise, and cognitive functioning tasks.
The results were that ““The present study demonstrated that [high cocoa flavanol] consumption prior to moderate exercise could effectively enhance exercise-induced improvements in [executive function], but not in [memory function], as shown by the early improvement in [executive function] induced by [high cocoa flavanol] consumption compared with [low coca flavanol] consumption. Therefore we suggest that the combination of [high coca flavanol] consumption and aerobic exercise may be beneficial for improving cognitive function.