The Depression Outcomes Study of Exercise (DOSE) was a study conducted at The Cooper Institute between July 1998 and October 2001. This was a two-phase study which evaluated the effects of aerobic exercise as the only treatment for mild to moderate major depressive disorder (MDD) AND whether the amount or dose of exercise is directly related to the alleviation of depressive symptoms. This concept is known as the dose-response relationship.
The participants included 80 men and women ages 20 to 45 years whom were diagnosed with mild to moderate MDD and not taking any medications. Participants were randomly placed in one of five exercise programs each with a different dose based on difficulty of exercise and frequency of exercise. Within these five programs, the difficulty of the exercise was measured by a “low dose” (LD) or “public health dose” (PHD), which was consistent with public health recommendations. All participants exercised in our laboratory for 12 weeks under supervision followed by 12 weeks of unsupervised exercise. Members of our staff, who were unaware of the participant’s treatment, measured symptoms of depression among these participants weekly during the supervised part of the treatment study. During the unsupervised 12 weeks, participants were permitted to exercise at home and were instructed to maintain an exercise log which included all information about their physical activity. These participants submitted their logs to the laboratory staff weekly at which time they were assessed for depressive symptoms.
In our study, we found that aerobic exercise is certainly effective as the only treatment in alleviating depressive symptoms especially for the public health dose groups. Depressive symptoms, as measured by the Hamilton Rating Scale for Depression, were reduced 47% in the public health dose groups whereas symptoms of depression for the low dose groups did not improve much from our control group. Further, we found that the frequency of exercise, either 3days/week or 5days/week, produced similar results in the alleviation of depressive symptoms. This suggests that the difficulty or intensity of the exercise is most effective in improving mild to moderate MDD, and a lower amount of exercise, relative to the public health recommendations, is not effective. As such, there now exists scientific evidence to suggest exercise alleviates symptoms of depression and such may be prescribed as treatment for a happier, healthier lifestyle.
|Dunn AL, Trivedi MH, Kampert JB, Clark CG, Chambliss HO.||The DOSE study: a clinical trial to examine efficacy and dose response of exercise as treatment for depression. Control Clin Trials. 2002 Oct;23(5):584-603.||Read Abstract|
|Dunn AL, Trivedi MH, Kampert JB, Clark CG, Chambliss HO.||Exercise treatment for depression: efficacy and dose response. Am J Prev Med. 2005 Jan;28(1):1-8.||Read Abstract|