Motivational and Behavioural Physical Activity as Differential Correlates of Well-Being Following Mass Trauma: A Three-Group Study of Direct, Vicarious, and Non-Exposed Individuals

Regular physical activity is associated with improved mental health, yet its role following mass trauma—and the differential contributions of motivational versus behavioural components—remains insufficiently understood. Drawing on stress-buffering and self-determination frameworks, this study examined whether value-based motivation for fitness and weekly vigorous physical activity are differentially associated with well-being as a function of trauma-exposure severity. A cross-sectional design was used with three groups (N = 306): survivors of the October 7, 2023 Nova music-festival attack (direct exposure; n = 74), university students assessed in 2024 (vicarious exposure; n = 82), and students assessed in 2022 (pre-event, non-exposed; n = 150). Measures included value fitness commitment (VFC), weekly vigorous physical activity (WPA), subjective happiness, somatic complaints, and PTSD symptoms (directly exposed group only). Group differences were examined using ANOVA/MANOVA. Associations and moderation effects were tested with correlation analyses and Hayes' PROCESS models controlling for age and family status. Directly exposed participants reported lower subjective happiness and higher somatic complaints than comparison groups. WPA was associated with fewer somatic complaints in the full sample and with lower PTSD symptom severity among directly exposed participants. VFC was associated with greater subjective happiness and fewer somatic complaints among directly exposed participants. Moderation analyses showed that the inverse association between VFC and somatic complaints was significant only in the directly exposed group, whereas WPA–well-being associations were not moderated by exposure level. Both motivational and behavioural physical-activity indices were linked to better well-being following trauma, but through partially distinct and context-dependent pathways. Value-based fitness commitment functioned as a protective resource specifically under conditions of severe trauma, consistent with stress-buffering and psychological-flexibility models, whereas actual vigorous activity showed a more general association with reduced somatic distress and PTSD symptoms. Low-cost, scalable physical-activity–related interventions that target both engagement and motivational processes may support post-trauma recovery.