Caffeine has little to no benefit after 3 nights of sleep restriction

http://www.eurekalert.org/pub_releases/2016-06/aaos-chl061316.php

Public Release: 13-Jun-2016
Caffeine has little to no benefit after 3 nights of sleep restriction
New study shows caffeine is not sufficient to prevent performance decline long term
American Academy of Sleep Medicine

A new study found that after restricting sleep to 5 hours per night, caffeine use no longer improved alertness or performance after three nights.

Results show that relative to placebo, caffeine significantly improved Psychomotor Vigilance Task (PVT) performance during the first 2 days, but not the last 3 days of sleep restriction.

"We were particularly surprised that the performance advantage conferred by two daily 200 mg doses of caffeine was lost after three nights of sleep restriction," said lead author Tracy Jill Doty, PhD, research scientist at Walter Reed Army Institute of Research. "These results are important, because caffeine is a stimulant widely used to counteract performance decline following periods of restricted sleep. The data from this study suggests that the same effective daily dose of caffeine is not sufficient to prevent performance decline over multiple days of restricted sleep."

•••••