Deep sleep: a key factor in muscle recovery after intense exercise

Deep sleep (slow-wave sleep — SWS) is a key sleep phase in which heart rate and breathing slow down and the body actively repairs tissue after exertion.^[2]

In a study of athletes following muscle-damaging exercise in the heat, subsequent deep sleep was found to increase in duration (both REM and SWS), providing a longer total sleep time and supporting recovery.^[1]

A systematic review shows that among the various sleep-improving interventions, it is precisely increasing sleep duration (including through deep sleep) that has the greatest positive effect on recovery and athletic performance.^[3]

Although deep sleep is a powerful recovery tool, athletes often experience sleep disturbances: when deep sleep and total sleep fall short, recovery worsens and the risk of overtraining and injury rises. That's why it's important to aim for quality sleep and to see a doctor promptly if health problems arise.^[3]