The influence of physical activity on the prevalence and remission of war-related mental disturbances has never been systematically evaluated. This study examined the influence of participation in the agricultural cycle on the posttraumatic stress disorder (PTSD) prevalence and correlated symptoms longitudinally in post civil war Mozambique. Prevalence rates were examined in the end and the outset of the agricultural cycle in a community population (N = 240). The agricultural cycle, which is characterized by fluctuations in physical activities, social connectedness, and the sense of purpose in life influences the PTSD prevalence and correlated symptoms. By studying the influence of the agricultural cycle on PTSD prevalence, severe PTSD cases that fail to respond to the agricultural cycle can be identified, and subsequently evaluated regarding the need for specialized care.