Investigating the Anxiolytic Effects of Aerobic Exercise for the Treatment of Posttraumatic Stress Disorder
Preliminary evidence has demonstrated the anxiolytic capabilities of aerobic exercise; however, the treatment potential for posttraumatic stress disorder (PTSD) has received comparably less attention. Aerobic exercise may work similar to interoceptive exposure therapy–an empirically supported treatment for PTSD–but this hypothesis has received scarce empirical attention. The current study investigated the therapeutic potential (i.e., whether or not PTSD symptoms, anxiety sensitivity [AS], and depressive symptoms would decline) and mechanisms (i.e., whether or not therapeutic benefit is changed by increasing or decreasing interoceptive awareness) of a brief aerobic exercise program for individuals with PTSD. Thirty-three participants (Mage=36.9 years; 76% female; 18% drop-out rate) with PTSD were recruited from the surrounding community and completed two weeks of aerobic exercise (six sessions) on a stationary bike. Participants were randomized into three groups to direct their cognitive focus during exercise, thereby testing hypothesized therapeutic agents; group one (cognitive distraction) watched a nature documentary, group two (exercise only) exercised in silence with no distractions, and group three (interoceptive exposure) received interoceptive prompts. Data was collected at pre-treatment, after each exercise session, and one week and one month after treatment ended. Hierarchal linear modeling indicated that each variable decreased significantly in a quadratic fashion; specifically, scores tended to reduce steadily from baseline to their lowest point after the last exercise session and steadily rose during the follow-up period. The effect of group membership was largely not statistically significant, whereas the interaction between time and group membership was significant among hyperarousal symptoms, fear of physical sensations, and fear of socially observable symptoms. In cases where interactions were present, between group comparisons suggested that the interoceptive prompts group consistently reported less change on primary outcome variables than the remaining groups. Given that the decline in outcome variables was present in each of the three study groups, results suggest that aerobic exercise is effective regardless of cognitive focus during exercise. Notwithstanding, given the subjacent impact of the intervention among interoceptive exposure group participants, anxiolytic properties of aerobic exercise may be accented in the short term by employing strategies to detract from the discomfort of the exercise protocol.