Physical exercise improves sleep quality, but its timing is crucial: while it is not the enemy of sleep, it is preferable to avoid intense sessions in the hour before bedtime to allow the body's temperature and arousal levels to subside.

noli's read

The advice is generally supported by current research, which has evolved toward a more nuanced view. While the myth that all nighttime exercise destroys sleep has been refuted, recent evidence, notably a large observational study published in Nature Communications, highlights that intense exercise in the four hours before sleep can delay sleep onset and reduce the quality of rest. Meta-analyses confirm that moderate to intense exercise can promote deeper sleep, provided enough time is allowed for core body temperature and heart rate to adjust. Matthew Walker presents a balanced approach here, acknowledging that the impact is highly individual and dependent on the intensity of the effort. There is no evidence that physical exercise is inherently harmful in the evening; the issue lies more in the physiological activation (temperature, sympathetic nervous system) linked to vigorous workouts too close to bedtime.

the sources

1. 1Lan L, Tsuzuki K, Liu YF, Lian ZW. 2017
2. 2Brown TM et al. 2022