Most athletes believe sleep is important for recovery, yet the importance of sleep for endurance athletes has remained unclear. A study published in the journal Sport & Exercise examined 9 endurance athletes under three experimental conditions: normal sleep, sleep restriction, and sleep extension.
Each condition required endurance cycling time-trials to be undertaken on four consecutive days, whereby nightly sleep was manipulated on intervening nights. Results showed that athletes better maintained endurance performance after three nights of sleep extension (8.5 hours per night). Compared with normal sleep (7 hours per night), an extra 90 minutes of sleep per night, over three consecutive nights, improved performance by an average of nearly two minutes (58.7 minutes vs. 56.8 minutes).
This study also found that endurance performance was impaired after just two nights of sleep restriction (5 hours per night).
This study shows the benefits of sleep extension for endurance performance and highlights the importance of cumulative sleep time for endurance athletes. Findings are particularly pertinent for endurance athletes required to compete over consecutive days, including cyclists during multi-day stage races. More broadly, other athletes competing over consecutive days (such as baseball players) or undertaking congested competition schedules may also benefit from sleep extension.