Posttraumatic stress disorder symptoms and associated physical activity levels among US service members

Posttraumatic stress disorder (PTSD) is associated with many physical and psychological comorbidites and adverse behaviors. The relationship between PTSD symptoms and positive health behaviors, however, is not well understood. The objective of this study was to examine the association of physical activity with prospectively assessed PTSD symptoms in a large military cohort. Baseline and follow-up questionnaire data from the Millennium Cohort Study, a large prospective study of US military service members, were used. Three types of physical activity – light/moderate, vigorous, and strength training - were assessed in relation to PTSD symptoms. Multivariable logistic regression was used to estimate adjusted odds of new-onset and persistent PTSD symptoms by physical activity levels at follow-up. Of the 38,883 study participants, 89.4% reported at least 30 minutes per week of any type of physical activity. New-onset PTSD symptoms were associated with lower levels of all activity types. Vigorous physical activity had the strongest, most consistent inverse association with PTSD symptoms. Individuals reporting at least 20 minutes of vigorous physical activity twice per week had approximately 40% reduced odds for new-onset and persistent symptoms. Previous studies examining the relationship between mental health and physical activity have focused on depression and anxiety. These findings contribute to emerging research in PTSD and associated physical activity and may lead to enhanced care for service members in the future.