• Posted July 17, 2024

Does Exercise Near Bedtime Really Disrupt Sleep? Maybe Not

Exercise near bedtime won't necessarily wreck a person's sleep, a new study says.

Intense exercise is typically discouraged as bedtime approaches, since such activity can disturb sleep by increasing body temperature and heart rate, researchers said.

But short resistance exercise "activity breaks" at regular intervals can actually improve a person's sleep, compared to winding down on a couch, researchers reported in the journal BMJ Open Sport & Exercise Medicine.

Simple, three-minute "activity breaks"involving chair squats, calf raises and standing knee raises with straight leg hip extensions added nearly an extra half-hour to a person's sleep, when performed at 30-minute intervals in the four hours before sleep, results show.

"These results add to a growing body of evidence that indicates evening exercise does not disrupt sleep quality, despite current sleep recommendations to the contrary,"concluded the research team led by Jennifer Gale, a doctoral candidate and sedentary behavior researcher with the University of Otago in New Zealand.

For the study, researchers recruited 30 people ages 18 to 40. All participants said they typically have more than five hours of sedentary time at work and two more hours in the evening.

Each of the participants completed two different sessions in a controlled laboratory experiment, separated by a minimum of six days.

In one session, they remained seated in the four hours prior to sleep. In the other, they performed 3 minutes of simple resistance exercises every half-hour.

Results show that the activity breaks led to an additional 27 minutes of sleep, on average, for the participants.

The resistance exercises also didn't cause any more sleep disturbances or awakenings than when people simply sat around before bedtime, researchers noted.

"Regularly interrupting prolonged sitting with short bouts of activity breaks is a promising intervention that may improve cardiometabolic health through multiple mechanisms,"researchers said in a journal news release.

Researchers speculated that these short bursts of resistance exercise could improve sleep by gently boosting metabolism and lowering blood sugar levels.

"Adults accrue the longest periods of sedentary time and consume almost half their daily energy intake during the evening, added to which insulin sensitivity is lower at this time,"the researchers noted.

The resistance exercises used in the study are simple to do, don't require any equipment and can be done while watching TV, researchers noted. This means they could easily become part of an average person's bedtime routine.

More information

The Sleep Foundation has tips for improving sleep.

SOURCE: BMJ, news release, July 16, 2024