For the one in three Americans that are sleep-deprived, working out with resistance exercises to strengthen muscles may produce longer and deeper shuteye than aerobics, new research from the American Heart Association shows. In a 12-month study, researchers randomly assigned 386 inactive, overweight adults with high blood pressure to one of several groups that worked out for an hour three times a week. A resistance exercise group did three sets of eight to 16 repetitions on 12 machines; the aerobics group used treadmills, bicycles or elliptical machines; a combo group used both; and a control group did no supervised exercise. Among the 42 percent of participants that were not getting at least seven hours of sleep at the study’s start, sleep duration increased by an average of 40 minutes for the resistance exercise group compared to an increase of about 23 minutes in the aerobic exercise group and about 17 minutes in the combined exercise group.

“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,” says study author Angelique Brellenthin, assistant professor of kinesiology at Iowa State University, in Ames.