The purpose of this study is to assess the effectiveness of an exercise program in improving antidepressant medication treatment for individuals with major depressive disorder (MDD).

Partial response to antidepressant treatment is common in people with MDD and is associated with significant morbidity and reduced quality of life. Pharmacological therapies have been used to augment the effect of antidepressants; however, such therapies are associated with a range of adverse effects. Studies indicate that exercise may be safe and effective in augmenting depression treatment. This study will determine whether exercise can complement selective serotonin reuptake inhibitor (SSRI) therapy in people with MDD who have residual symptoms of depression despite drug treatment.

Participants will be randomly assigned to either high frequency exercise or low frequency exercise for 12 weeks. Depression symptoms will be measured weekly. Quality of life and satisfaction with the study will also be measured. Depression scales and self-reports will be used to assess participants.

Ages Eligible for Study:  18 Years   -   70 Years,  Genders Eligible for Study:  Both

Criteria

Inclusion Criteria:

• Diagnosis of Major Depressive Disorder
• Score of 14 or higher on the Hamilton Depression Scale (HAM-D)
• 8 to 12 weeks of SSRI treatment, with at least 6 weeks at adequate doses
• Sedentary lifestyle
• Physically capable of exercise
• Body mass index (BMI) less than 40 kg/m2
• Willing and able to comply with study requirements

Exclusion Criteria:

• Significant cardiovascular disease or other medical conditions
• Uncontrolled hypertension
• Abnormal exercise stress test
• Hematologic disorders
• Comorbid disorders, including depression due to another comorbid condition, psychotic disorder, bipolar disorder, schizophrenia, schizoaffective disorder, eating disorder, or obsessive compulsive disorder (OCD)
• Alcohol and/or substance abuse in the past 6 months
• Hospitalization for mental illness within the past year
• High suicide risk
• Use of psychopharmacological or psychotherapeutic treatment other than SSRIs
• Failure to respond to two or more adequate pharmacological treatments during the current depressive episode
• Significantly elevated blood lipids
• Pregnancy