Independent associations between cardiorespiratory fitness, waist circumference, BMI, and clustered cardiometabolic risk in adolescents.

The purpose of this study was to examine the independent associations between measures of adiposity and cardiorespiratory fitness (CRF) with clustered cardiometabolic risk in adolescents. 209 adolescents (139 boys), aged 15-17.5 years participated. Participants completed anthropometric measurements [height, weight, waist circumference (WC)] whilst the 20 m fitness test was used to assess CRF. Additional measures included systolic blood pressure, triglycerides, ratio total cholesterol/high-density lipoprotein cholesterol, insulin resistance (HOMA), interleukin-6, C-reactive protein (CRP), and adiponectin. Partial correlations revealed weak to moderate negative associations for body mass index (BMI) and WC with CRF (r = -0.295 and -0.292, P < 0.001) and adiponectin (r = -0.227 and -0.262, P < 0.05). Weak to moderate positive associations were evident for BMI with CRP, and cardiometabolic risk (r = 0.274, and 0.283, P < 0.05, respectively). Weak to moderate positive associations were apparent for WC with CRP and triglycerides (r = 0.240 and 0.254, P < 0.05), whilst moderate to large associations were evident for WC with clustered cardiometabolic risk (r = 0.317, P < 0.05). Regression analyses revealed that BMI was positively associated with cardiometabolic risk (β = 0.243, P < 0.001). Further analysis whilst additionally controlling for WC and CRF strengthened this association (β = 0.352, P < 0.001). Finally, participants in the least-fit quartile for CRF had significantly poorer cardiometabolic risk scores than those in the other quartiles. BMI and not CRF was independently associated with cardiometabolic risk. Reducing BMI appears essential to minimize cardiometabolic risk during adolescence.