Wednesday, December 5, 2007

Exercise Yourself to Sleep

Occasionally, after a vigorous workout you’ll hear someone say, “I’ll sleep well tonight”. Without a doubt, I have found that I don’t sleep as well on days that I am not able to exercise. But what does the literature have to say about this phenomenon of “exercising yourself to sleep”?

A study published in the Journal of the American Medical Association examined the impact of moderate exercise on sleep quality in older adults with moderate sleep-related complaints. In this study, 43 men and women between the ages of 50 and 76 were split into two groups. One group exercised moderately (30- to 40-minute aerobics classes four times a week) for 16 weeks, while the other group made no changes to their lifestyles. After 16 weeks, the exercisers showed improvement over the control group in general quality of sleep, quicker sleep-onset, longer sleep duration and feeling rested in the morning

Another study conducted at Tufts University took 32, “slightly to moderately depressed” elderly men and women and assigned them to an exercise group or a control group. The exercise group performed three strength training sessions each week. At the end of the 10 week study the exercise group reported not only significant improvement in sleep quality over the control group, but improvement in quality of life also.

Women who have gone through menopause are noted to be at higher risk for sleep problems. Researchers have found that postmenopausal women who performed moderate-intensity exercise for at least a half-hour every morning had fewer problems falling asleep compared to less active women.

Relatively few research studies have looked at the impact of exercise on insomnia. The ones that have support the premise that exercise improves sleep patterns, primarily by increasing total sleep time and decreasing sleep latency. To maximize the benefit of exercise, it appears that the duration of exercise is more important than its intensity. Also, it is preferable that exercise occur 5 to 6 hours (minimum of 3 hours) before bedtime.


Anne said...

With work, kids, dinner, etc - sometimes I don't get to exercise until 8 or 9 at night. Sometimes I find myself "hyped up" and tough to go to sleep after. I have tried to wake up early and exercise, but it's tough.

Do you think it's better to wake up early and exercise or exercise later when I am more awake - even though I may end up laying in bed awake because of it?

Thanks! I like this new blog format.

Kent W. Davidson, M.D. said...

Anne---If you have consistently found yourself "hyped up" at bedtime from exercising late in the evening, I would try to exercise early in the morning. I've heard that if you do something on a daily basis for 21 days, it becomes a habit. In this case a very healthy habit. Thanks for reading our blog.