For the study, researchers enrolled 386 adults who met the criteria for overweight or obesity, which was a body mass index from 25-40 kg/m².
Participants were inactive and had elevated blood pressure, measuring from 120-139 mm Hg systolic (top number) and 80-89 mm Hg diastolic (bottom number). Participants were randomly assigned to a no-exercise group (for comparison) or one of three exercise groups (aerobic only, resistance only, or combined aerobic and resistance) for 12 months.
Everyone in the exercise groups participated in supervised 60-minute sessions, three times a week, with the combination exercise group doing 30 minutes of aerobic and 30 minutes of resistance exercise.
Study participants completed a variety of assessments at the start and at 12 months including the self-reported Pittsburgh Sleep Quality Index (PSQI), which measures sleep quality.
Researchers also measured sleep duration; sleep efficiency (how much time one is actually asleep divided by the total amount of time the individual is in bed); sleep latency (how much time it takes to fall asleep after getting into bed); and sleep disturbances (how frequently sleep is disturbed by things like being too hot or too cold, snoring or coughing, having to use the bathroom or having pain). Scores on the PSQI indicate better quality sleep, ranging from 0 for the best sleep to 21 as the worst possible sleep. Scores greater than five are considered “poor quality sleep”.