DR. CAT FITZGERALD, PT, DPT & CSCS.
For many runners, there isn’t really a lot of wiggle room for scheduling their runs. Between work, commuting, family responsibilities, and social commitments, a lot of runs happen when they can… which usually means early in the morning or in the evening.
Evening runners often ask if running so late has a negative effect on their sleep. It’s a commonly held belief, but so is the idea that later exercise makes you tired and helps you sleep. So which is true?
A recent meta-analysis from the Journal of Sports Medicine analyzed the data from 23 different studies to determine “the extent to which evening exercise affects sleep and whether variables such as exercise intensity or duration modify the response”.
Generally, the study found that evening exercise actually improved the quality of sleep–decreasing the amount of time spent in stage one and increasing the amount of slow-wave sleep. However, the intensity mattered. Higher body temperature at bedtime and a higher level of physical stress were associated with lower sleep efficiency. Higher body temperature also led to more wake time after sleep onset.
So overall, exercise in the evening is good for your sleep! If you plan on a speed workout or more intense run, try to do it earlier than normal to mitigate the negative effects of more intense exercise.
Stutz K Eiholzer R Spengler CM. “Effects of evening exercise on sleep in healthy participants: a systematic review and meta-analysis”. Sports Med. 2019; 49(2): 269-287.