Stanford study is the first to document how sleep extension affects the performance of actively competing athletes
A study in the July 1 issue of the journal SLEEP shows that sleep extension is beneficial to athletic performance, reaction time, vigor, fatigue and mood in collegiate basketball players. The study is the first to document sleep extension and the athletic performance of actively competing athletes.
Results of objective measurements show that the mean total sleep time per night during sleep extension was 110.9 minutes longer than at baseline. Indices of athletic performance specific to basketball were measured after every practice to assess changes in performance. Speed during 282-foot sprints improved significantly from 16.2 seconds at baseline to 15.5 seconds after sleep extension, and shooting accuracy increased significantly by nine percent on both free throws and three-point field goals. Subjects also reported improved overall ratings of physical and mental well-being during practices and games.
"Following multiple weeks of sleep extension, elite athletes demonstrated improvements in specific indicators of basketball athletic performance including higher shooting percentages and faster sprint times," said lead author Cheri D. Mah, MS, researcher at the Stanford Sleep Disorders Clinic and Research Laboratory in Stanford, Calif. "Subjects also demonstrated faster reaction time, decreased levels of daytime sleepiness, and mood improvements."
The study involved 11 healthy students on the Stanford University men's varsity basketball team and was conducted during two basketball seasons from 2005 to 2008. Participants had a mean age of 19 years and an average height of about six feet and four inches. Eight of the players were guards, two were forwards and one was a center.
Total sleep time was measured objectively by actigraphy. The players maintained their habitual sleep-wake schedule for a baseline period of two to four weeks during the NCAA basketball season, sleeping for an average of less than seven hours per night. The following period of sleep extension lasted five to seven weeks, during which the participants obtained as much nocturnal sleep as possible with a minimum goal of 10 hours in bed per night. Objective mean total sleep time during sleep extension was nearly 8.5 hours per night.
Participants shot 10 free throws from 15 feet, making an average of 7.9 shots at baseline and 8.8 shots at the end of the sleep extension period. They also attempted 15 three-point field goals, making an average of 10.2 shots at baseline and 11.6 shots after sleep extension. The timed sprint involved running from baseline to half-court and back to baseline, then the full 94-foot length of the court and back to baseline. Reaction time, levels of daytime sleepiness, and mood were monitored using the Psychomotor Vigilance Task, Epworth Sleepiness Scale and Profile of Mood States.
Mah said that she was especially intrigued to find that sleep extension was associated with improvements in diverse basketball skills.
"It was interesting to note that sleep extension significantly improved different measures of physical performance in basketball from shooting percentages to sprinting times," she said.
According to Mah, an athlete's nightly sleep requirement should be considered integral to attaining peak performance in all levels of sports. She offered these tips to help athletes improve their performance by maximizing their sleep:
- Prioritize sleep as a part of your regular training regimen.
- Extend nightly sleep for several weeks to reduce your sleep debt before competition.
- Maintain a low sleep debt by obtaining a sufficient amount of nightly sleep (seven to nine hours for adults, nine or more hours for teens and young adults).
- Keep a regular sleep-wake schedule, going to bed and waking up at the same times every day.
- Take brief 20-30 minute naps to obtain additional sleep during the day, especially if drowsy.
Mah presented preliminary results from this study at SLEEP 2007, the 21st annual meeting of the Associated Professional Sleep Societies, in Minneapolis, Minn. The results are consistent with similar research she has performed at Stanford involving men and women who compete in other sports such as football, tennis, and swimming.
Although this was not an industry supported study, Philips Respironics loaned actigraphy devices to the study investigators.
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