A yearlong resistance exercise program for inactive adults with hypertension improved sleep quality and duration compared with aerobic exercise, combined aerobic and resistance exercises and no exercise, researchers reported.

Angelique Brellenthin

Poor sleep quality is associated with high BP and elevated cholesterol; regular short sleep, defined as less than 7 hours per night, can increase risk for CV events, Angelique Brellenthin, PhD, assistant professor of kinesiology at Iowa State University in Ames, Iowa, and colleagues wrote in an abstract. The American Heart Association recommends aerobic physical activity to improve sleep; however, there are limited data on the effects of other popular types of physical activity, such as resistance exercise, on sleep.

“While resistance exercise is not often considered a front-line lifestyle intervention to improve CV health — as opposed to aerobic or ‘cardio’ exercise — resistance exercise may have substantial indirect effects on CV health, nonetheless, by improving the duration and quality of sleep,” Brellenthin told Healio.

Brellenthin and colleagues analyzed data from 406 inactive adults aged 35 to 70 years (53% women) with overweight or obesity and stage 1 hypertension at high risk for CVD. Researchers randomly assigned participants to one of four exercise groups: aerobic exercise only (n = 101), resistance exercise only (n = 102), combined aerobic and resistance exercises (n = 101) and a no-exercise control group (n = 102) for 1 year. All exercise participants performed time-matched supervised exercise three times per week for 60 minutes per session; the combined exercise group performed 30 minutes each of aerobic and resistance exercises at 50% to 80% of their maximum intensity. Participants completed the Pittsburgh Sleep Quality Index (PSQI) at baseline and 12 months; only participants with complete baseline data on all PSQI subscales were included (n = 386).

Primary outcomes were the PSQI total sleep quality score, sleep duration in hours, sleep efficiency (defined as time asleep/time in bed), sleep latency (time to fall asleep) and sleep disturbances (a combination of the number and frequency of disturbances).

Within the cohort, 94% of participants completed the intervention with an 83% exercise adherence rate.

For all groups, including controls, PSQI total scores and sleep disturbances decreased significantly. Among participants who reported getting less than 7 hours of sleep at baseline, sleep duration increased by a mean of 40 minutes for participants in the resistance exercise group, by a mean of 23 minutes in the aerobic exercise group, a mean of 17 minutes in the combined exercise group and a mean of 16 minutes in the control group.

Within groups, sleep efficiency increased in the resistance exercise (P = .0005) and combined exercise groups (P = .03), but not in the aerobic exercise (P = .97) or control groups (P = .86; P = .04 for between-within groups interaction).

Sleep latency also decreased by a mean of 3 minutes for participants in the resistance exercise group (P = .003), although the overall between-within groups interaction effect was not significant.

Brellenthin said more research is needed regarding the ideal amount of resistance exercise for clinical improvements and the potential mechanisms linking resistance exercise with improved sleep, particularly those that might differ from traditional aerobic exercise mechanisms.