There just aren’t enough hours in the day, especially in today’s always on, always on-the-go, and always plugged-in society. Between work and home, trying to carve out any time for yourself to exercise can seem an impossible task, especially with the commonly held belief that working out in the evening is bad for sleep.
But now, a new study may be able to put the idea that high-intensity evening exercise disrupts sleep to rest.
Researchers from Charles Sturt University in Australia found that evening exercise does not negatively impact sleep quality and could even help suppress appetite.
The research was published in the journal Experimental Physiology.
Eleven middle-aged men were recruited for the study which involved experimental trials of high-intensity exercise in the morning, afternoon, and evening to see if working out had any impact on sleep or feelings of hunger.
Participants completed cycling exercises with six one-minute bursts of high intensity broken up by four minutes of rest. Blood samples were drawn both before and after the exercise sessions, and the participants had their sleep monitored.
Evening exercise did not negatively impact sleep quality for the participants, and after analyzing the blood samples, the researchers found that evening exercise correlated with a bigger decrease in hunger-stimulating hormone levels.
The researchers found that time of day did impact how intensely the participants exercised.
“Interestingly, power output during the sprint efforts was higher for the afternoon and evening trials compared to the morning trial, indicating that participants were able to perform better during latter parts of the day,” said Penelope Larsen, the lead author of the study. “Therefore, time-of-day may also need to be considered when planning training schedules.”
The study only involved a small group of middle-aged men, so there are limitations to the study’s findings, and the results may not apply across different age-groups or sexes.
“In the future, we hope to conduct similar studies recruiting women, to determine whether sleep and appetite responses may be different depending on sex,” said Larsen. “Also, this study only considered a single bout of exercise; therefore, it would be beneficial to investigate long-term sleep, and appetite adaptations to high-intensity exercise training performed either in the morning, afternoon or evening.”