DALLAS — Sleep has been especially hard to come by for countless people over the past two years, which is certainly understandable. Between an ongoing pandemic and seemingly unrelenting inflation, there’s no shortage of topics to keep us up at night lately. You’ve probably already heard that exercising can help improve sleep issues, but now research reports resistance-based exercises like push-ups and weight lifting may offer greater sleep benefits than aerobics.
“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,” says study author Angelique Brellenthin, Ph.D., assistant professor of kinesiology at Iowa State University in Ames, Iowa, in a media release. “Aerobic activity is often recommended to improve sleep, yet very little is known about the effects of resistance exercise versus aerobic exercise on sleep. Our study is one of the largest and longest exercise trials in a general adult population to directly compare the effects of different types of exercise on multiple sleep parameters.”
We all know sleep is important. Pull a few all-nighters in a row and no amount of coffee is going to keep you feeling normal. Simply put, sleep is a necessity not a luxury. More specifically, however, this project focused on sleep’s benefits in reference to heart health in particular. Plenty of prior studies show that failing to attain enough adequate sleep on a regular basis increases the risk of hypertension considerably, as well as elevated cholesterol and atherosclerosis.
On a related note, lack of sleep is also linked to obesity, bodily inflammation, and diabetes – which all just so happen to be associated with cardiovascular disease. Sleeping too little, and even too much, increases one’s risk of stroke, heart attack, and death.
Connecting resistance exercise to sleep
To study the relationship between various forms of exercise and sleep, researchers gathered 386 adults considered either obese or overweight (BMI: 25-40 kg/m²). All participants led largely inactive lifestyles, and showed elevated blood pressure, measuring between 120-139 mm Hg systolic (top number) and 80-89 mm Hg diastolic (bottom number).
All study subjects were separated randomly into various experiment groups. One group served as a control cohort (no exercise at all), while three additional groups (aerobic only, resistance only, or a mixture of aerobic and resistance exercises) were formed. All groups stuck to their prescribed routines for a full year. Across all three exercise groups participants engaged in supervised one hour sessions three times weekly. The combo group spent 30 minutes on cardio and another half hour on resistance exercises during each session.
Subjects assigned to the aerobics group could choose between using a treadmill, exercise bike, or elliptical. While subjects worked out, their heart rates were monitored to ensure they stayed within the prescribed heart rate range for a moderate-to-vigorous intensity exercise. Meanwhile, the resistance exercise group worked out on 12 resistance machines encompassing a variety of muscle groups: chest press, lat pulldown, leg curl, leg extension, biceps curl, triceps pushdown, shoulder press, abdominal crunch, lower back extension, leg press, and so on. Subjects were instructed to complete three sets of 8-16 repetitions at 50-80 percent of their one-rep maximum.
The cardio/resistance combination group, meanwhile, engaged in a half hour of moderate-to-vigorous aerobics followed by another 30 minutes of resistance workouts consisting of two sets of 8-16 repetitions on nine machines.
Both before and after the 12-month experimental exercising period, subjects completed a survey designed to measure sleep quality. Questions on sleep duration, sleep efficiency (time spent sleeping divided by total time in bed), and sleep disturbances (frequency of waking up due to any number of annoyances – temperature, snoring, coughing, pain, urge to use the bathroom) were all part of the surveys as well.
A lower score on the PSQI indicates better quality sleep (0 indicates near perfect slumber, while 21 indicates major insomnia issues). Generally, any score greater than five was deemed “poor quality sleep” by the research team.
‘Far superior exercise option’
All in all, the study reports a number of noteworthy findings:
- To start, over a third (35%) of all participants met the criteria for poor sleep at the beginning of the study.
- A full 42 percent of subjects were failing to attain seven hours of sleep nightly to start. Among this group, by the end of the study, sleep duration increased by an average of 40 minutes among the resistance group. The combination exercise group saw an increase of 17 minutes, and the aerobics group displayed an uptick of 23 minutes. Even the control group ended up sleeping 15 minutes longer.
- Regarding sleep efficiency, only the resistance and combo groups saw improvements.
- Sleep latency dropped by three percent among the resistance exercisers, but no other latency improvements were seen in the other two cohorts.
- Both sleep quality and sleep disturbances improved across all four groups, even those who weren’t exercising at all.
All in all, study authors conclude resistance exercises appear to be a far superior exercise option when it comes to getting some better shuteye and improving overall health health to boot.
“While both aerobic and resistance exercise are important for overall health, our results suggest that resistance exercises may be superior when it comes to getting better ZZZs at night,” Dr. Brellenthin concludes. “Resistance exercise significantly improved sleep duration and sleep efficiency, which are critical indicators of sleep quality that reflects 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.”
Further work on this topic should utilize objective sleep monitoring instead of self-reported sleep questionnaires to rectify one of the few limitations in reference to this project.
This research was presented at the American Heart Association’s Epidemiology, Prevention, Lifestyle & Cardiometabolic Health Conference 2022.