Regular exercise is well-known to promote a good night’s sleep, but exactly which type of exercise has remained a mystery until now. A new preliminary study demonstrates how resistance-style workouts, such as weightlifting, provide the most significant increases in sleep quality and duration.
The study, yet to be peer-reviewed, was conducted by Iowa State University scientists and was designed to discover the connections between a physically active lifestyle, sleep, and cardiovascular health. Previous studies have revealed strong associations between poor sleep habits and cognitive decline, high cholesterol, and increased risk of stroke and heart disease. This is why the new study’s authors set out to learn more about which types of exercise would be most effective at helping people mitigate these risks.
Angelique Brellenthin, a study author, said:
“It is increasingly recognized that getting enough sleep, particularly high-quality sleep, is important for health including cardiovascular health. Unfortunately, more than a third of Americans don’t get enough sleep on a regular basis. Aerobic activity is often recommended to improve sleep, yet very little is known about the effects of resistance exercise versus aerobic exercise on sleep.”
The scientists recruited 386 overweight or obese adults who were inactive and had high blood pressure. Then, participants were randomly assigned to either a resistance exercise group, an aerobic exercise group, a combined resistance, and aerobic exercise group, or a non-exercise group as a control. Over 12 months, participants partook in supervised one-hour-long exercise sessions three times per week.
Assessments conducted at the start and end of the study observed the following:
- Sleep latency (how long it takes to fall asleep)
- Sleep duration,
- Sleep efficiency (sleeping time versus overall time in bed),
- Sleep disturbances,
- Sleep quality.
Overall, 35% of the participants had poor sleep quality at the start of the study, and 42% were not getting the recommended seven hours of sleep. After one year, the scientists observed an average 23-minute increase in sleep duration per night in the aerobic exercise group, which participated in treadmill running and recumbent bike sessions. The resistance group, which completed weight-training exercises targeting every major muscle group, experienced an average 40-minute increase in sleep duration. And finally, the combined group, which participated in 30 minutes of both exercise types, experienced an average 17-minute sleep duration increase.
The study also found that sleep latency dropped by an average of three minutes in the resistance group only, and sleep efficiency improved in the resistance and combined exercise groups, but not in the aerobic-only group.
“While both aerobic and resistance exercise is important for overall health, our results suggest that resistance exercises may be superior when it comes to getting better ZZZs at night. Resistance exercise significantly improved sleep duration and sleep efficiency, which are critical indicators of sleep quality that reflect how well a person falls asleep and stays asleep throughout the night.
Therefore, if your sleep has gotten noticeably worse over the past two stressful years, consider incorporating two or more resistance exercise training sessions into your regular exercise routine to improve your general muscle and bone health, as well as your sleep.”
The scientists presented their findings at the American Heart Association’s Epidemiology, Prevention, Lifestyle and Cardiometabolic Health Conference in Chicago earlier this month.