A School of Medicine study on the men’s basketball team published in this month’s issue of Sleep concluded that sleep extension — an increase in the time spent sleeping over baseline amounts — leads to improved athletic performance.

The research team measured sleep patterns during a two-week baseline evaluation, then asked 11 members of the team to sleep at least 10 hours a night over a five-to-seven-week period. Researchers then tested the athletes’ shooting accuracy and sprint times.

“[The traditional athletic-training regimen] has a lot of emphasis on the physical training: the conditioning, the workouts,” said Cheri Mah ’06 M.S. ‘06, first author and researcher at the Stanford Sleep Disorders Clinic and Research Laboratory. “When you get to Stanford, there’s a little bit more of the nutrition, obviously coaching plays a big factor, but in all of these emphases, there hasn’t been one on sleep and recovery.”

A main goal of the study was to eliminate accumulated sleep debt, which researchers assumed the athletes carried with them upon starting the study, to naturally improve athletic performance. At the study’s conclusion, free-throw shooting accuracy increased by an average of nine percent, three-point field goal accuracy increased by an average of 9.5 percent and average sprint times decreased by about five percent.

Despite the basketball team’s rigorous travel schedule, the athletes pursued the study, though it was difficult to get them to agree initially. The athletes received compensation.

“It was tricky, but generally I’ve had a very good relationship with many of the coaching staff and athletes and teams on Stanford’s campus, and it was the individual athletes’ decision to participate in the study,” Mah said.

The researchers initiated the study with several teams in order to have a sample size large enough to ensure accurate results, but ultimately decided it was not possible to compare statistics between sports. They chose to focus on the men’s basketball team, looking at physical performance measures specific to the sport over the regular winter season.

During the study, researchers also asked athletes to refrain from drinking coffee and alcohol. When sleeping at least 10 hours a night was not an option, the athletes were asked to take naps to make up for missed nocturnal sleep hours.

“Every single person on this planet, with the rare exception, is going to benefit from getting a good night’s sleep,” said sports performance coach Juan Pablo Reggiardo, who works specifically with the men’s basketball team. “It’s not just for physical performance, it’s that mental alertness and focus.”

Along with physical performance testing, researchers tested reaction time with the Psychomotor Vigilance Task, levels of daytime sleepiness using the Epworth Sleepiness Scale and mood through the Profile of Mood States. As a result of added sleep, daytime sleepiness and mood both improved.

“These improvements following sleep extension suggest that peak performance can only occur when an athlete’s overall sleep and sleep habits are optimal,” the study said.

Although the study does not prove that sleep extension can help recreational athletes or non-athletes, research has shown that sleep awareness can benefit the average person.

William Dement, professor of psychiatry, teaches Sleep and Dreams, a class that focuses on understanding sleep and sleep debt.

“Stanford students likely know more about sleep than any other university, although there

are a few other universities who address the issue,” said Dement in a statement Mah provided to The Daily. “Sleep and Dreams certainly made Stanford students more aware about sleep, whether they took the course or gained knowledge about sleep through word of mouth from Sleep and Dreams students.”

Mah hopes to continue sleep research, bringing similar studies to different sports teams

and groups of people.

“The bigger picture in all of this is that we’re hoping to continue to build on this, not just in terms of research, but in trying to continue to develop resources and education and understanding of sleep as an important part of athletic performance and training for a lot of the Stanford teams and athletes and coaches,” she said.