Physical Fitness, Hemodynamic and Affective Responses to Psychosocial Stress in Women

Abstract

PURPOSE: Studies suggest that adaptations resulting from regular physical exercise training might positively impact physiological adaptations to psychological stressors. A reduced physiologic sensitivity to psychosocial stressors may be one mechanism by which physical fitness may serve to buffer the deleterious effects of chronic stress. However, to date, there has been limited study of the relationship between physical fitness and physiological and affective stress responding in women which considers the profound influence of the ovarian cycle on physiological and affective responses to stress. This study aims to investigate the relationship between physical fitness and physiological and affective responses to stress in women, while considering ovarian cycle phase effects on the stress response. METHODS: Following a two-tiered screening process, 10 healthy women (18-45y) who were medication-free and had regular menstrual cycles were enrolled. Participants completed an enrollment visit, (including perceived stress assessment and assessment of cardiorespiratory fitness via maximal oxygen consumption during exercise); and a psychosocial stressor protocol for the collection of hemodynamic [blood pressure (SBP, DBP) and heart rate (HR)], affective, and hormonal stress responses. Psychosocial stress testing sessions occurred during the follicular phase of the menstrual cycle to control for hormone fluctuations which can influence the physiological response to stress. RESULTS: Preliminary results from this ongoing study show a trend for higher levels of physical fitness to be associated with lower SBP (r= -.58, p = 0.08) and DBP (r= -.56, p = 0.09) reactivity to stress. Interestingly, higher physical fitness was significantly associated with a more negative affective response to the psychosocial stressor tasks (speech: r = .70, p = .02, math: r = .71, p = .02). CONCLUSIONS: If confirmed in our larger sample, results suggest a possible dissociation of the physiological and psychological stress responses associated with physical fitness in women during the follicular phase of the menstrual cycle.