Original articleFitness is a Stronger Predictor of Fasting Insulin Levels than Fatness in Overweight Male Middle-School Children
Section snippets
Methods
Children (n = 106) at a single middle school with a body mass index above the 95th percentile for age participated in this study. Over a 24-month period, each participant underwent testing at the University of Wisconsin Exercise Science Laboratory before and at the conclusion of the 9-month school year during a single visit after an overnight fast, supervised by the same investigators. The procedures were approved by the Human Subjects Committee, and informed written consent was obtained before
Results
Patient characteristics are presented in the Table as mean ± SD. At study enrollment, mean age of the study participants was 12.8 ± 1.4 years, and 55% of the subjects were female. The mean body mass index (BMI) was 30.8 ± 5.9 (males 31.7 ± 6.9, females 30.1 ± 5.0; P = .237), and mean percent body fat (%BF) was 35.8 ± 5.5 (males 36.0 ± 6.3, females 35.6 ± 4.9; P = .462). Mean measurement of Vo2max/kgLBM at study initiation was 62.0 ± 16.4 mL/kg/min for females, 68.3 ± 16.4 mL/kg/min for males (P
Discussion
This study shows that, like adults, cardiovascular fitness is an equal, perhaps even more important predictor of insulin sensitivity than is fatness in children. Differences in the interactions between CVF and %BF with sex have been noted previously.16 Our data suggest that the adverse effects on FI levels were most profound in males with high %BF and low CVF. In one prior study of older adolescents, when CVF (assessed by sub-maximal Vo2 consumption) and %BF were analyzed together, for boys,
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Cited by (0)
Supported by grants from Genentech Center for Clinical Research and the UW Sports Medicine Classic Fund.