The relationship between cardiorespiratory fitness and blood pressure among airline pilots: a mediation analysis of body composition

Abstract

Objective: Blood pressure (BP), cardiorespiratory fitness (CRF), and body composition are independently associated with health outcomes, yet the relationship between these variables has not been explored among airline pilots. The aim of this study was to evaluate the relationship between CRF and BP, and further examine whether the relationship is mediated by body composition. Methods: A cross-sectional study was conducted among 356 airline pilots in New Zealand. We measured height, body mass, BP, waist circumference, skinfolds, and CRF (via a WattBike cycle ergometer submaximal VO2max test). Partial correlation coefficients were estimated to examine the relationships between all variables while controlling for age and sex. Haye's PROCESS macro and the Sobel test were utilized for the mediation analysis. Results: All body composition variables (body mass index, waist circumference and body fat percentage) were positively correlated with all BP variables (systolic pressure, diastolic pressure and mean arterial pressure) (P < 0.001). CRF was negatively correlated with all body composition and BP variables (P < 0.001). The Sobel test and indirect effect were significant (P < 0.001), confirming that all body composition variables partially mediate the relationship between CRF and all blood pressure variables. Conclusion: Lower CRF is associated with higher blood pressure, and body composition partially mediates the relationship between these health risk factors. These findings highlight the importance of physical fitness and healthy body composition in the management of blood pressure among this occupational group.