Tossing back two shots of coffee each hour may provide more sustainable stimulation than gulping down a large cup in the morning, scientists from Rush University Medical Center report in the journal Sleep. In the study, sixteen men stayed in windowless rooms for nearly a month while the researchers screwed with their circadian rhythms. From a Scientific American article about the findings:
“In the new study, the scientists… tested the effects of administering an hourly, low dose of caffeine equivalent to about two ounces of coffee to one group, while the second group received a placebo. The caffeinated men performed better on cognitive tests than the control individuals did, and dozed off less often. And though they received the same cumulative dose as subjects in previous, single-dose studies, taking many small doses minimized some of the negative side effects that caffeine can have, such as tremors.” Link