Sex-specific Changes in Metabolic and Musculoskeletal Biomarkers After Acute Resistance Exercise in Healthy Young Adults

Exercise induces acute biochemical signaling between muscle, bone, and adipose tissues that may influence whole-body metabolism and musculoskeletal adaptation. This investigation examined sex-differences in concentrations of circulating biomarkers associated with metabolic and musculoskeletal regulation before and after an acute resistance exercise test. During baseline assessments for a longitudinal exercise training study, 37 participants (22 males and 15 females) completed an acute resistance exercise test consisting of a 6 set×10-repetition back squat at 75% of their one-repetition max. Blood samples were collected before and immediately after the acute resistance exercise test to quantify biomarker concentrations. Total body DXA determined body composition. Sex-differences in absolute changes from pre- to post-exercise in biomarker concentrations were examined. After adjusting for baseline lean mass, a significant interaction was observed for irisin (p=0.043); concentrations increased in males (∆1.1±0.3µg/mL, p<0.001) but not females (p=0.515). After adjusting for baseline bone mineral content, a significant main effect of time (∆12.7±1.5pmol/L; p<0.001) was observed for sclerostin. After adjusting for baseline fat mass, significant interactions were observed for leptin (p=0.040) and HMW adiponectin (p=0.003). Leptin concentrations decreased in females (∆-7.9±2.5ng/mL, p=0.004) but not males (p=0.689). HMW adiponectin increased in females (∆630.5±194.8ng/mL, p=0.007) but not males (p=0.213). A significant interaction was observed for insulin (p=0.004), which increased in females (∆9.7±2.1μIU/mL, p<0.001) but not males (p=0.426). A significant main effect of time was observed for glucose (∆1.8±0.3mg/dL; p<0.001). Sex-specific changes in biomarkers associated with metabolic and musculoskeletal regulation were evident following acute resistance exercise and may explain differences in health and adaptation.