Should you wind down with calming activities or go all out with an intense workout for a restful night's sleep? While it's well-known that daytime physical activity can enhance sleep quality, rigorous exercise before bed is often discouraged.
Contrary to conventional sleep advice, a new study has found that evening exercise does not disrupt sleep quality. According to the study published in BMJ Open Sports and Exercise Medicine, incorporating resistance exercise "activity breaks" at night can improve sleep duration.
"We know higher levels of physical activity during the day promotes better sleep, but current sleep recommendations discourage high-intensity exercise before bed because it can increase body temperature and heart rate resulting in poor sleep quality," lead author Jennifer Gale said in a news release.
"However, many sleep guidelines tell us we shouldn't do longer bouts or higher intensity exercise in the hours before sleep, so we wanted to know what would happen if you did very short bouts of light intensity activity repeatedly throughout the evening," she added.
To understand the effects of brief bursts of intense exercise on sleep quality, the researchers observed 30 non-smokers, aged 18 to 40, who were engaged in two different interventions. In one, they were made to sit uninterrupted for four hours, while in the other, sitting was interspersed with three-minute activity breaks every half hour.
During the activity breaks, the participants performed three rounds of three exercises, each lasting 20 seconds: chair squats, calf raises, and standing knee raises with straight leg hip extensions. Participants followed along with a video recording of a person demonstrating the exercises.
"These simple, bodyweight exercises were chosen because they don't require equipment or a lot of space and you can do them without interrupting the TV show you are watching. From what we know from other studies, you could probably get a similar effect if you walked around your house, marched on the spot, or even danced in your living room – the most important thing is that you get out of your chair regularly and move your body," primary investigator Dr. Meredith Peddie said.
The results showed that after the activity breaks, participants slept for an additional 27 minutes on average, compared with prolonged sitting.
"The average sleep duration was 7 hours 12 minutes, compared with 6 hours and 45 minutes after prolonged sitting. While the time at which participants attempted to go to sleep was more or less the same, average wake times differed. Participants woke, on average, at 7:35 am after the prolonged sitting intervention and 8:06 am after regular activity breaks," the news release stated.
However, the study has certain limitations. The researchers caution that the findings were based on a small group of people and conducted in a laboratory setting, which may not reflect real-life behavior.
