Skeletal Muscle Oxidative Capacity is Linked to Cardiovascular Health

Abstract

Background Cardiovascular disease (CVD) affects 48% of the adult population and is the leading cause of death in the United States. Vascular stiffness, endothelial dysfunction, and decreased skeletal muscle health are each independently associated with increased CVD risk. This study sought to test the hypothesis that indices of vascular health are associated with skeletal muscle function in the general population. Methods 22 (16 women and 6 men) apparently healthy adults participated in this study. Dual energy x‐ray absorptiometry was performed to obtain body composition and skeletal muscle mass. Carotid‐femoral pulse wave velocity (PWVCF), augmentation index normalized for heart rate (AI@75bpm), and flow mediated dilation normalized for shear rate (FMD/Shear) were assessed to evaluate arterial stiffness and endothelial function. Handgrip strength was assessed using a handgrip dynamometer and skeletal muscle mitochondrial oxidative capacity (Kox cap) was assessed using near‐infrared spectroscopy (NIRS) to evaluate indices of skeletal muscle health and function, respectively. Results Kox cap was inversely correlated with both carotid‐femoral pulse wave velocity PWVCF (r= −0.515; p= 0.014) and AI@75BPM (r= −0.453; p= 0.034). In addition, a trend in the relationship between FMD/Shear and Kox cap (r= 0.326; p= 0.139) was observed. Compared with women, men had significantly higher PWVCF (p= 0.008), handgrip strength (p< 0.001), and skeletal muscle mass (p= 0.006); however, muscle function was similar (p= 0.209) between sexes. Conclusions These findings demonstrate that improved muscle function can favorably impact vascular health. Additionally, skeletal muscle strength and size were significantly different between sexes; however, muscle function was similar. These data highlight the importance of assessing all three indices of muscle health. Future studies are warranted to investigate if increases in vascular endothelial function will improve skeletal muscle function and contribute to prevention of CVD. Support or Funding Information This project was supported in part by The Augusta University Medical Scholars Program (AB) and NIH R01DK117365 (RAH and XW).