Work Out Early or Late? Here’s The Answer
As any busy person can attest, getting control of your sleep schedule and finding the time to exercise often go hand in hand, but finding the right balance between the two can be tricky. Is it better to take an hour after work for your daily burn, or is getting up early for a sunrise jog the way to go?
New research being presented next week at the American College of Sports Medicine’s annual meeting may have an answer. The relationship between sleep and exercise, according to study abstracts, goes both ways: Exercising in the morning leads to better sleep at night, and getting up early means you’re more active during the day.
The morning wins.
Addressing the first half of that equation, researchers at Appalachian State University in North Carolina decided to see how exercising at different times of day affects the quality of sleep the same night. Twenty middle-aged subjects were made to exercise at moderate intensity for 30 minutes at 7 a.m., 1 p.m. and 7 p.m. on separate days, and then had their sleep monitored each night by electrode sensors.
When exercising in the morning, the subjects slept more soundly at night. They woke up fewer times and spent significantly less time in REM sleep—a state of light sleep from which sleepers wake up easily.
Exercising in the afternoon and evening corresponded to roughly an hour more of REM sleep, on average, than working out in the morning.
On the other side of that equation, not only is morning exercise good for sleep, but rising early is good for exercise and diet.
Two teams at Brigham Young University in Utah examined exercise and diet separately.
Regarding exercise, researchers fitted 375 college-age women with accelerometers and measured their physical activity and sleep schedules for seven days. Although the amount of sleep subjects got in a given night positively correlated with their next-day exercise, the biggest predictor was how early they awoke. For every hour after 7:30 a.m. the subjects rose, their level of daily exercise dropped.
“Arising earlier in the morning may significantly increase physical activity, which may be due to simply having more time to be active during the day,” the author concludes.
Other BYU researchers found a similar relationship between diet and sleep patterns. A similar cohort—375 college-age women—had their sleep patterns monitored for a week, during which the subjects reported back on what they ate.
The team found that going to bed earlier, waking up earlier and keeping a consistent sleep schedule corresponded with eating less junk food, more fruits and veggies and meeting dietary recommendations.