New research shows a lack of sleep can cause an athlete performance to fall significantly. The research, carried out by scientists at the University of California, showed energy expenditure during submaximal exercise decreased 3.9 percent; maximal aerobic power decreased 2.9 percent and time to exhaustion decreased by 10.7 percent (37 seconds). Submaximal heart rate decreased after sleep restriction, as well as peak heart rate and Psychomotor Vigilance Test response speed.
“Our study is unique since we examined the relationship between sleep, physical performance, cognitive functioning, and physiology simultaneously,” said lead investigator, Cheri Mah, MS. “Future studies are needed to better understand the physiologic responses to sleep restriction, and conversely sleep extension, to understand the dose response of sleep interventions on performance and health.”
The study involved 12 healthy elite male cyclists who either had restricted sleep to 4 hours for three days or extended sleep to 10 hours for two weeks. Cyclists completed a baseline week of habitual sleep and a 2-week washout period in between interventions. Outcome measures pre and post intervention included: a 20-minute submaximal test, a 1-minute incremental maximal exercise test, and a maximal time to exhaustion test on a bicycle ergometer and metabolic collection system as well as the Psychomotor Vigilance Test.