Muscular performance isn’t as good early in the morning as it is later in the day. That’s what the results of a study from Toledo, Spain’s University of Castilla-La Mancha indicated after highly resistance-trained men were divided into groups and asked to do the same workout but at different times of day. The problem stems from the body’s circadian rhythm. Thankfully, the researchers went a step further to figure out how people who train in the morning can overcome this unfair disadvantage. The answer, it turns out, is caffeine, which has the power to reverse the circadian rhythm’s effects on neuromuscular performance. When subjects supplemented with caffeine prior to training alongside those who went without, their strength soared well beyond that of their caffeine-less brethren and actually matched the performance of the group that trained in the evening. The researchers also looked at the strength of subjects’ muscle contractions, as well as testosterone and cortisol levels. By having a direct effect on the muscle, caffeine increased neuromuscular performance to totally level the playing field for subjects who trained in the morning.

Reference: R. Mora-Rodriguez et al., PLoS One, 2012;7 (4):e33807. Epub 2012, Apr 4.