Practicing an endurance and resistance sport before sleeping prevents you from falling into the arms of Morpheus.
- After doing endurance and resistance exercises an hour before bed, young athletes’ sleep quantity and quality deteriorate.
- Brain activity makes adaptive changes in response to exercise, increasing alpha and theta3 power during certain stages of sleep.
- Endurance sports led to elevated cortisol levels, suggesting hyperarousal.
While some people practice physical activity in the morning, others do it in the evening after work. But does this have an impact on sleep? This is the question that researchers in sleep physiology from the University of Caen and the Caen University Hospital wanted to answer. In a recent study, they looked at the effects of resistance and endurance exercises performed before bed. Specifically, they tested the hypothesis that evening exercise can lead to a level of neurophysiological arousal that could disrupt sleep.
Degraded quantity and quality of sleep due to endurance and resistance exercises
To carry out their work, the scientists recruited 16 young athletes, aged 21 to 27, in good health. Participants entered a laboratory to undergo three counterbalanced pre-sleep conditions, including a resistance exercise session, an endurance exercise session (30 minutes each, beginning 1 hour before bedtime), and a control condition. during which the adults remained seated. Then, the volunteers’ sleep, brain activity, movements and breathing were measured.
The results, published in the journal Frontiers in Physiology, showed that sleep quality was lower after doing resistance and endurance exercises. After this intense effort, total sleep time was also lower. According to the authors, analyzes of spectral power, carried out using an electroencephalogram, revealed an increase in alpha and theta3 power (brain wave frequencies) during certain phases of sleep after both types of exercise. “These increases could reflect adaptive changes in nighttime brain activity in response to exercise,” they clarified.
Hyperarousal: endurance sports increase cortisol levels
According to the study, endurance activity caused an increase in brain activity associated with an increase in beta spectral power during sleep and an elevation in cortisol levels, suggesting hyperarousal. Resistance exercise led to lower beta power and lower cortisol levels.
“This study highlights significant changes in sleep quality and quantity after moderate endurance and resistance exercises in the evening. However, these effects cannot be considered deleterious. (…) Although these results confirm the physiological effects of evening exercise on sleep, it is necessary to reproduce them with larger samples and taking into account other physiological parameters, such as circulating melatonin secretion and variations in body temperature”, concluded the team.
