A new study of nearly 15,000 people found that the window of late-night workouts in which sleep is then impacted is actually much larger than previously thought, showing that exercising within four hours of bedtime can have a detrimental effect on shut-eye.
Monash University researchers looked at international data from 14,689 people who were monitored with a multi-sensor biometric gadget for a year, which equaled four million nights of information to analyze. The tracking device, a WHOOP Strap, recorded exercise data, sleep and cardiovascular activity.
But the scientists weren’t looking at the impact of any exercise; they were more interested in how more intense workouts might have enduring heart-rate variabilities throughout the night. What they found was a link between night exercise and delayed sleep onset and less sleep achieved throughout the night, as well as a higher resting heart rate than seen in those who worked out earlier in the day.
“Intense exercise in the evening can keep the body in a heightened state of alertness, which is why public health guidelines have previously advised against working out too close to bedtime,” said Josh Leota, from the Monash University School of Psychological Sciences. “However, findings from controlled laboratory studies are less conclusive, with many suggesting that evening exercise doesn’t necessarily disrupt sleep.
“These studies have relied on small sample sizes and laboratory settings, and rarely involved exercise bouts that elicit substantial cardiometabolic demand on the body, calling into question the external validity of such findings,” he added.
Read more at: https://newatlas.com