Department of Exercise, Nutrition & Health Sciences, University of Bristol, Bristol, England, United Kingdom.
Med Sci Sports Exerc. 2010 Aug;42(8):1502-10. doi: 10.1249/MSS.0b013e3181d322c4.
Examine whether cardiometabolic risk factors are predicted by fitness or fatness among adolescents.
Participants are 4955 (2614 female) sixth-grade students with complete data from 42 US middle schools. Fasting blood samples were analyzed for total cholesterol, HDL- and LDL-cholesterol, triglyceride, glucose, and insulin concentrations. Waist circumference and blood pressure were assessed. Body mass index (BMI) was categorized as normal weight, overweight, or obese as a measure of fatness. Fitness was assessed using the multistage shuttle test and was converted into gender-specific quintiles. Gender-specific regression models, adjusted for race, pubertal status, and household education, were run to identify whether BMI group predicted risk factors. Models were repeated with fitness group and both fitness and fatness groups as predictors.
Means for each risk factor (except HDL, which was the reverse) were significantly higher (P < 0.0001) with increased fatness and differed across all BMI groups (P < 0.001). Waist circumference, LDL-cholesterol, triglycerides, diastolic blood pressure, and insulin were inversely associated with fitness (P < 0.001). When both fatness and fitness were included in the model, BMI was associated (P < 0.001) with almost all cardiometabolic risk factors; fitness was only associated with waist circumference (both genders), LDL-cholesterol (males), and insulin (both genders). Other associations between fitness and cardiometabolic risk factors were attenuated after adjustment for BMI group.
Both fatness and fitness are associated with cardiometabolic risk factors among sixth-grade youth, but stronger associations were observed for fatness. Although maintaining high levels of fitness and preventing obesity may positively affect cardiometabolic risk factors, greater benefit may be obtained from obesity prevention.
研究青少年的心血管代谢风险因素是由体能还是体脂决定的。
参与者为来自美国 42 所中学的 4955 名（女性 2614 名）六年级学生，他们具有完整的数据。对空腹血样进行总胆固醇、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇、甘油三酯、葡萄糖和胰岛素浓度分析。测量腰围和血压。体重指数（BMI）作为体脂的衡量标准，分为正常体重、超重或肥胖。使用多阶段穿梭测试评估体能，并转换为性别特异性五分位数。进行性别特异性回归模型，调整种族、青春期状态和家庭教育，以确定 BMI 组是否预测风险因素。使用体能组和体能与体脂两组作为预测因素重复模型。
随着体脂的增加，除了高密度脂蛋白（呈相反趋势）外，每种风险因素的平均值（P<0.0001）都显著升高，且在所有 BMI 组之间存在差异（P<0.001）。腰围、低密度脂蛋白胆固醇、甘油三酯、舒张压和胰岛素与体能呈负相关（P<0.001）。当模型中同时包含体脂和体能时，BMI 与几乎所有心血管代谢风险因素均相关（P<0.001）；而体能仅与腰围（两性）、低密度脂蛋白胆固醇（男性）和胰岛素（两性）相关。在调整 BMI 组后，体能与心血管代谢风险因素之间的其他关联减弱。
肥胖和体能均与六年级青少年的心血管代谢风险因素相关，但肥胖的相关性更强。尽管保持高水平的体能和预防肥胖可能对心血管代谢风险因素产生积极影响，但预防肥胖可能会带来更大的益处。
