Higher Physical Fatigue Predicts Adherence to a 12-week Exercise Intervention in Women with Elevated Blood Pressure

Objective: To investigate predictors of exercise adherence to a 12-week exercise intervention for sedentary women and men with elevated blood pressure (BP).

Methods: Fifty-one otherwise healthy and unmedicated adults (27 women and 24 men) with elevated BP (≥120/80 mmHg but <179/109 mmHg) participated in a 12-week exercise intervention involving cardiovascular and strength training. Participants kept weekly exercise logs detailing minutes spent exercising each week. The following were assessed before and after the intervention: cardiorespiratory fitness (in mL/kg/min), body mass index (BMI), level of habitual physical activity, physical fatigue, self-efficacy for exercise habits, and social support.

Results: Regression analysis revealed that mean exercise minutes/week were predicted by higher age (p < .05), higher cardiorespiratory fitness (p < .05), and a gender by physical fatigue interaction (p < .01; R2 = 0.34, F = 3.248, p < .01). Women who reported higher physical fatigue prior to the intervention spent more time exercising during the 12-week intervention than those with lower levels of physical fatigue. This relationship persisted after controlling for age, BMI, cardiorespiratory fitness, level of habitual physical activity prior to the intervention, self-efficacy for exercise habits, and social support (p < .01). The gender by physical fatigue interaction explained 13.9% of the variance in mean minutes exercised/week above and beyond the effects of covariates.

Conclusion: Both gender and fatigue should be considered when developing exercise interventions, such that more initial physical fatigue in women is associated with a tendency to devote greater amounts of time to exercising.