Relationship between thigh muscle mass and augmented pressure from wave reflections in healthy adults.

Skeletal muscle may be viewed as an endocrine organ that releases numerous factors with the potential to influence vascular tone. Previous cross-sectional studies have shown an inverse relationship between muscle mass and arterial stiffness. We examined the relationship between muscle mass, arterial pressure in the aorta and brachial artery, and pressure from wave reflections [characterized as heart rate corrected augmentation pressure (AP)] and augmentation index (AIx). Twenty-seven (13 male, 14 female) subjects who were non-smokers and had no known cardiovascular or metabolic diseases visited the laboratory for two sessions of testing. Upon arriving for the first session, mid-thigh muscle (mCSA) and fat (fCSA) cross-sectional area were assessed using peripheral Quantitative Computed Tomography. Following this, concentric one-repetition maximum (1-RM) testing was completed to assess knee extensor strength. The second visit consisted of taking brachial and aortic blood pressure measurements. A significant positive relationship was found between mCSA and brachial systolic blood pressure (r = 0.47, p = 0.02), but not between mCSA and aortic systolic blood pressure (r = 0.35, p = 0.09). There was an inverse association between mCSA and AP75 (-0.49, p = 0.01) and AIx75 (-0.49, p = 0.01). In conclusion, muscle mass is associated with brachial systolic blood pressure and inversely associated with pressure from wave reflections. Our findings suggest a link between global musculo-skeletal integrity and cardiovascular hemodynamics in young healthy adults.