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Date of Award


Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Doctor of Psychology (PsyD)

Committee Chair

Paula Truax

Second Advisor

Sydney Ey

Third Advisor

Michel Hersen


The present study examined the effectiveness of aerobic exercise with a trainer and cognitive psychotherapy as a treatment program for MDD. The study was a multiple baseline, single subject design that used three undergraduate female students from a local University that met DSM-IV criteria for MDD. Participants were randomly assigned to begin with twice weekly exercise treatment sessions for three weeks followed by twice weekly cognitive therapy sessions for three weeks or vice versa. In each condition two additional hours of exercise or cognitive exercise were completed individually by the participant. Depression was the primary assessment of interest but satisfaction with life, automatic thoughts, and stage of change were also assessed. Results indicated that both treatments were effective at decreasing depressive symptoms; furthermore exercise treatment was slightly more effective. The largest decrease in symptoms happened in whatever treatment was received first regardless of if it was cognitive or exercise treatment. Mode specific changes were non-conclusive but it was noted that automatic thoughts tended to decrease while in the cognitive treatment. No significant conclusions regarding the possible role that cognitive therapy and or trainers might play in increasing attrition and compliance rates could be made. This study highlighted the methodological difficulties found in many other studies with in this area. Future research might want to utilize personal trainers in a more gradually and personally designed exercise programs.