I came across a very interesting study in the Journal of Adolescent Health this week. 434 Swiss teenagers were studied to see what the effect of exercise on sleep patterns was. 258 of the participants were athletes, who averaged 17.7 hours/exercise a week, and 179 were non athletes, who averaged 4.7 hours/exercise a week. All of the participants kept sleep and exercise diaries for 7 consecutive days and completed a number of questionnaires about the quality of their sleep and other psychological measurements.
The researchers found that the athletes had better sleep quality, and that it took them less time to fall asleep at night than the non-athletes. The athletes also had fewer awakenings during the night than the non-athletes. The athletes were less sleepy and had better concentration during the day, as well as less anxiety and fewer depressive symptoms than the non-athletes. The findings were more pronounced in males than in females.
Exercise has many health benefits, both physical and mental. It improves mood, and reduces the risk of heart disease, osteoporosis, diabetes, and some cancers. Exercise keeps weight down, and improves sexual function. It also has a number of positive effects on sleep. It increases deep sleep, and as shown in this study, helps one fall asleep faster and stay asleep, improving daytime concentration and overall function. This effect doesn't seem to be because of physical exhaustion, but due to actual changes seen in brain wave patterns, as another study by the same group, published in the World Journal of Biological Psychiatry in July 2009, demonstrated.