Exercise and Quality of Sleep

Sleep difficulties are common among middle-aged and older adults, often resulting in sedative-hypnotic prescriptions that can result in deleterious effects such as confusion, falls, and drowsiness. Although health professionals typically believe that exercise may be of some benefit for sleep quality, there is little scientific substantiation of this premise.

This 16-week randomized, controlled trial studied 43 otherwise healthy individuals aged 50-76, who had moderate sleep complaints as assessed by the Pittsburgh Sleep Quality Index, were not involved in any regular exercise program, and had no other condition that could likely directly affect sleep patterns (e.g., excess alcohol intake, chronic pain, depression).

Treatment group subjects were assigned a gradually increasing intensity aerobic exercise sufficient to produce 60-75% of heart rate reserve as based upon treadmill peak heart rate. These subjects engaged in four exercise sessions per week, containing at least 30 minutes of aerobic activity (i.e., brisk walking, stationary cycling, low impact aerobic classes).

In exercise subjects, sleep duration was increased by almost one hour, sleep-onset latency was reduced by almost one-half, overall sleep quality was improved, and feeling of being well-rested upon awakening was improved. The authors conclude that moderate-intensity exercise improves sleep in older adults with moderate sleep complaints.

Kin A, et al. JAMA 1997;277:32-37.