Initiating and Maintaining Physical Activity in Depressed Individuals

The investigators propose a randomized clinical trial in which 240 depressed individuals are assigned to one of three arms, with each successive arm having an added component that may serve to increase and maintain physical activity:

1. brief advice (BA) to exercise (control condition);
2. BA + supervised \& home-based exercise (SHE) + health education (HE) contact control; and
3. BA + SHE+ cognitive-behavioral sessions focused on increasing and maintaining exercise (CBEX).

The primary aim is to assess and optimize the safety, feasibility, acceptability of each intervention component, as well as barriers limiting their effectiveness in order to prepare for a larger scale randomized clinical trial.

The investigators propose a randomized clinical trial in which 240 depressed individuals are assigned to one of three arms, with each successive arm having an added component that may serve to increase and maintain physical activity:

1. brief advice (BA) to exercise (control condition);
2. BA + supervised \& home-based exercise (SHE)+health education (HE) contact control; and
3. BA+SHE+ cognitive-behavioral sessions focused on increasing and maintaining exercise (CBEX).

There are two phases for participants: intervention phase (3 months), which consists of intensive contact, and the follow-up phase (6 months). BA will consist of one, 45-minute session about public health recommendations, and strategies for getting started. SHE will be a 12-week intervention consisting of 1x/week supervised exercise plus exercise prescriptions for home-based exercise with the goal of gradually achieving the public health recommendation of 150 minutes/week of moderate-to-vigorous physical activity (MVPA), CBEX and HE sessions will be individual, 30-minute, weekly sessions during the intervention phase. CBEX will address barriers to physical activity that are particularly pronounced in depression -i.e., anhedonia, decreased motivation, and decreased energy, as well as poor problem-solving skills. During the follow-up phase, groups who received SHE during the intervention phase will receive brief, monthly phone check-ins from an exercise specialist.

Primary Aims:

1. To compare the efficacy of the 3 arms for increasing physical activity during the 12-week intervention phase. We hypothesize that BA + SHE + CBEX will be superior to BA + SHE + HE, and that BA + SHE + HE will be superior to BA alone in terms of objectively measured MVPA levels.
2. To compare the longer-term impact of the three arms on objectively-measured minutes of MVPA at 6- and 9-month follow-ups (i.e., follow-up phase). Hypotheses are the same as for the intervention phase (aim #1).

   Secondary Aims:
3. To assess the impact of proposed intervention combinations on depression, physical health outcomes including cardiorespiratory fitness and body composition, and self-reported MVPA in all phases. Hypotheses mirror those described in our primary aims above.
4. To determine whether amount of MVPA mediates the association between group assignment and change in depressive symptoms. We hypothesize that amount of MVPA will serve as a mediator.
5. To examine behavior change theory-based mediators of the association between group assignment and MVPA. Hypothesized mediators include: perceived benefits of exercise, perceived barriers to exercise, exercise self-efficacy, intrinsic motivation to exercise, and identified motivation to exercise.
6. To examine whether social and environmental barriers to exercise predict exercise maintenance.

Eligibility Criteria:
Inclusion Criteria:

1. Sedentary, i.e., have not participated regularly in moderate-to-vigorous physical activity (MVPA) for 90 minutes per week or more for more than 6 weeks of the past 12 weeks.
2. Medically cleared for MVPA, documented by a note from their primary care provider.
3. No significant medical condition or physical disability that would interfere with physical activity or study participation. The investigators will exclude individuals with significant cardiovascular disease, hematologic disorders, and autoimmune disorders. The investigators will also exclude individuals who are planning a surgery in the next 9 months and those with dementia.
4. Elevated depression symptoms. To meet criteria for elevated symptoms, participants must have a QIDS score of 8 or greater (i.e., at least moderate depression levels), and must have a score of "1" or greater on at least one of the two core DSM-V depressive symptoms, i.e., sad mood or anhedonia. -
5. No current bulimia or anorexia (past 3 months); no MDD with psychotic symptoms (past 6 months); no history of bipolar disorder, schizophrenia, or a chronic psychotic condition; (assessed using the SCID).
6. No hazardous drug or alcohol use in the past 6 months, as assessed by: a. no substance abuse treatment in the past 6 months; and b. does not meet criteria for a moderate or severe substance use disorder in the past 6 months.
7. Depression is not very severe, i.e., QIDS score is \<= 20.
8. No suicidality requiring immediate treatment.
9. Not pregnant or planning on becoming pregnant in the next year.
10. Understands English sufficiently well to consent and complete study assessments.
11. Aged 18-65.
12. Able to make one of the 2 available exercise class times.
13. Able to walk 1 mile
14. Weight does not exceed 375 lbs.
15. If participants are aged 60 or older, or if there is any concern about their cognitive capacity, participants will undergo a brief cognitive functioning screener, the Montreal Cognitive Assessment (MOCA). Participants are required to achieve a score within 1 SD of the mean for their age and education level to participate in the study.