UC San Diego

Background: Associations between physical and emotional stress and negative mood states have been documented in a variety of populations. In military personnel, more physical symptoms and decrements in ability, to perform critical tasks have been shown to accompany such stress-induced negative mood. Most research in this area has focused on immediate effects of stress on mood. Purpose: We wondered what immediate mood effects strenuous training would have on Marines, what mood effects would endure 30 and 90 days after completion of training, and how mood scores would compare with normative data. Methods: Sixty male Marines (M age = 19 years, range = 18-28) completed the Profile of Mood States (POMS) at multiple time points before and after participating in a 30-day, cold weather, high-altitude field training exercise. Anthropometric measurements were taken at the same time points. Results: The Marines reported significant increases in POMS scores from baseline to completion of training, most of which endured up to 90 days. The anger and fatigue scores reported by the Marines were comparable to adult male psychiatric outpatient norms. Conclusions: Rigorous training in challenging environments may result in enduring negative moods that approach levels of clinical significance and may have implications for readiness for duty and performance of critical tasks. Behavioral medicine interventions may be helpful in military populations to reduce the impact of negative mood.