THE ENERGY REQUIREMENTS IN INDIVIDUALS WITH MENTAL RETARDATION

为了表征智力迟钝（MRs）个体的能量代谢特征，我们测量了23名智力迟钝男性和相同数量的男性志愿者在不同体力活动水平（基础、仰卧、坐位、站立和以30、50和70 m/min的速度行走）下的能量消耗、最大耗氧量（Vo_2max）和身体组成。两组分别匹配年龄、身高和体重。能量消耗采用道格拉斯袋法测量。采用新开发的六氟化硫（SF_6）稀释法测定体成分。此外，采用三维加速度计评估身体运动，并测量血浆中常量营养素的指标。结果：MRs在以30和50 m/min的速度坐、站和行走时的能量消耗显著高于对照组（p<0.05），而两组的基础代谢率和静息代谢率相似。MRs组Vo_2max显著低于对照组（P<0.05）。加速测量显示mr的过度运动，这可能解释了他们运动时更高的能量消耗。相比之下，在体脂百分比和瘦体重方面没有观察到显著差异。与对照组相比，MRs患者血浆总胆固醇、甘油三酯和白蛋白浓度显著降低。我们的研究结果表明，与非MRs相比，MRs的能量代谢负担更低。他们日常生活中有限的体育活动可能是原因。在制定适当的饮食计划和体育活动计划时，应考虑到这些能量代谢特征

To characterize energy metabolism in individuals with mental retardation (MRs), We meaured energy cost at several physical activity levels (basal, supine, siffting, standing, and walking at 30,50 and 70 m/min), maximal oxygen consumption (Vo_2max), and body composition in 23 male MRs and the same number of volunteer male controls. Both groups were individually matched for age, body height, and body weight. Energy costs were measured by the Douglas bag technique. The recently developed sulfur hexafluoride (SF_6) dilution technique was employed for measuring body composition.In addition, 3-dimensional accelerometry was used for evaluating body movements, and plasma indices of macronutrients were also measured. Results : The energy cost of MRs, when sitting, standing, and walking at 30 and 50 m/min, was significantly higher than that of controls (p<0.05), while the basal and resting metabolic rates were similar in both groups. Vo_2max was significantly lower (P<0.05) in MRs than controls. Accelerometry demonstrated excessive movements in MRs, which may explain their higher energy cost of exercise. By contrast, no significant difference was observed in percent body fat and lean body mass. Concentrations of plasma total cholesterol, triacylglycerols and albumin were significantly lower in MRs compared with controls.Our findings suggest that MRs are burdened with energy metabolism less economical than non-MRs. A limited physical activity in their daily life may be the cause. These characteristics of MRs' energy metabolism should be considered for planning their proper dietary schdules and physical activity programs