The funding agency, DoD, determined that the study could not meet its enrollment numbers by the end of the grant.

The primary objective of this pilot intervention study is to examine the efficacy of exercise for reducing the symptoms of posttraumatic stress disorder (PTSD) and other psychiatric and somatic symptoms. The sample will be composed of veterans aged 18-65 with combat-related PTSD (N = 40). Participants will be randomly assigned to one of two groups. Participants in the exercise training group (n = 20) will receive three 60-75 minute sessions per week of combination aerobic and resistance training for eight weeks. In the control stretching group, participants (n = 20) will receive training in whole-body flexibility three times per week for eight weeks. Secondary objectives include 1) determining feasibility of the intervention (as measured by the percentage of prescribed days of exercise completed by each participant, and percentage of time exercising completed at the prescribed intensity and duration); 2) determining the influence of exercise training on aerobic fitness and strength in the sample; and 3) determining whether psychiatric/somatic symptom improvements are associated with improvements in fitness and strength. Finally, exploratory objectives will include examining whether exercise training can improve early signs of heart disease, and whether certain biomarkers (using MRI and fMRI data and inflammatory markers) are associated with treatment response.

Inclusion Criteria:

1. Ages 18-65yr
2. Diagnosis of PTSD
3. CAPS >30
4. Reported combat exposure per the Deployment Risk and Resilience Inventory (DRRI)
5. Sedentary lifestyle (planned activity for purpose of health < 2 days/wk)
6. Capability of giving informed consent

Exclusion Criteria:

1. Abuse of alcohol or drugs
2. Homelessness
3. Significant cognitive impairment (e.g., MMSE score of ≤ 26) that would hinder ability to understand the protocol
4. Signs or symptoms of cardiovascular, metabolic or pulmonary disease that would preclude participating in the exercise, including uncontrolled hypertension (> 159/99 mm Hg)
5. Usage of beta blockers, which could influence the heart rate response to exercise
6. Any physical or mental health condition that would contraindicate participation in the study (e.g., musculoskeletal, orthopedic, and/or neuromuscular disorders)
7. High suicidality
8. Below cutoff on either STAI (<30) or PCL-M (<40)
9. Pregnancy or plans to become pregnant in the next 4 months
10. Excessive levels of physical activity assessed via interview and pedometer recording
11. Current treatment for PTSD (drug or counseling) for a duration of less than eight weeks
12. Clinically judged to be unsuitable for participation by the research physician