Circulating Adiponectin and Resistin Levels Are Associated with Adiposity Indices and Physical Fitness in Healthy Adult Males.

BACKGROUND The aim of this study was to assess the correlation of physical fitness scores (PFS) with serum adiponectin, resistin, and adiponectin/resistin ratio (AR ratio) in relation to body adiposity indices in healthy adult males. MATERIAL AND METHODS This cross-sectional study was conducted at the Clinical Physiology Unit, Physiology Department, King Saud University Medical City, King Saud University, Riyadh, from March 2017 to April 2018. We included 125 healthy adult males. Serum samples were obtained after overnight fasting. Analysis was performed for fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), basal insulin, lipid profile, resistin, and adiponectin. Bioimpedance analysis (BIA) was used to assess body composition. Based on ideal body composition, PFS were computed as previously published for all subjects and compared with serum markers. RESULTS There was a positive correlation of adiponectin with PFS (r=.218, p=0.015) and an inverse correlation with obesity degree (OD), OD (r=-.239, p=0.001), body mass index (BMI) (r=-.244, p=0.001), and waist/hip ratio (WHR) WHR (r=-.296, p=0.001). Moreover, it was correlated negatively with basal insulin (r=-.211, p=0.009) and homeostatic insulin resistance model (HOMA-IR) HOMA-IR (r=-.221, p=0.013). Resistin was correlated negatively with PFS (r=-.203, p=0.023), while its correlation with OD, BMI, WHR, and HOMA-IR was not significant. AR ratio was positively correlated with PFS (r=.286, p=0.001) and negatively with OD (r=-.210, p=0.019), BMI (r=-.222, p=0.013), WHR (r=-.308, p=0.001) and basal insulin (r=-.237, p=0.008). In linear regression analysis, the relationship of PFS was significant with adiponectin (r=.218, p=0.015), resistin (r=-.203, p=0.023) and AR ratio (r=.286, p=0.001). ROC curve analysis showed that individually the values of adiponectin and resistin were not significantly correlated with PFS, but they were significant with the combined AR ratio with AUC 64.6% (p=0.029). CONCLUSIONS Serum adiponectin was positively correlated and resistin was negatively correlated with physical fitness scores based on healthy body composition with low proportion of body adiposity and a higher proportion of fat-free mass. However, the combined effect of adiponectin/resistin ratio is an even better predictor of physical fitness. Moreover, the adiponectin/resistin ratio is even more highly associated with physical fitness than adiponectin or resistin alone.