CHILD MOBILITY: ROLE OF STRENGTH, BODY FAT & ENERGY COST

力量是决定机动状态的最重要因素 在运动障碍儿童中。 肥胖，一个常见的问题 在残疾儿童中，是第二个重要的负面因素， 影响残疾儿童的行动能力。 本研究 重点是力量和身体脂肪作为能源成本的决定因素 在不同年龄的儿童中， 脊髓脊膜膨出（MM）导致的活动障碍程度， 脊髓损伤（SCI）、脑瘫（CP）和Duchenne 肌营养不良症（DMD）。 具体而言， 建议将解决两个假设：1）过量的身体脂肪 增加了安培和轮椅运动的能量消耗 除了与瘦肉组织相关的增加的成本之外 缺陷和虚弱，以及2）运动的能量消耗较高 与每日总能量消耗的减少有关 (TEE)和体力活动;减少体力活动将 与肥胖增加有关。 研究人群 由375名6至20岁的男女儿童组成：90 MM、45 SCI、120例CP、30例DMD和90例对照。 测量包括：1） 人体测量学，2）全身和局部身体组成， 双能X线吸收测定法（DXA），3）定量等轴测 手肘和膝盖的等速力量，4）休息 代谢率（RMR）间接量热法，5）能源成本 步行和/或轮椅运动（ml O2/Kg米和 大卡/公斤计）通过便携式遥测代谢测量 TEE和身体活动指数（TEE/RMR比值） 连续三天的心率（HR）监测。 能量 运动成本将在基线时进行评估， 体重通过骨盆带相当于增加10%的身体 脂肪和20%的身体脂肪增加。 康贝特人将以 相对重要性的弱点和下降的比例瘦肉 组织与总体重的比例增加， 运动，减少身体活动（如由 TEE：RMR比率）和残疾人肥胖增加的风险 孩子 能源经济的客观措施， 运动和身体活动在功能上是相关的 结果。建立双方的关系 力量和肥胖增加，增加能源成本，和 因此，减少体力活动，将提供一个基础， 改善功能性活动的干预措施。 结局研究 评估旨在改善能源状况的干预措施， 运动的效率也需要考虑身体 随着时间的推移，如果确实存在显著的 在运动过程中增加的能量成本与 肥胖增加。

Strength is the most important determinant of mobility status among children with motor impairments. Obesity, a common problem among disabled children, is a second important factor negatively influencing mobility status in disabled children. this study focuses on strength and body fat as determinants of energy cost of ambulation and wheelchair locomotion in children with variable degrees of mobility impairment due to myelomeningocele (MM), spinal cord injury (SCI), cerebral palsy (CP), and Duchenne Muscular dystrophy (DMD). Specifically, the primary aims of the proposal will address two hypotheses: 1) excess body fat increases the energy cost of ambulation and wheelchair locomotion over and beyond the increased costs associated with lean tissue deficits and weakness, and 2) higher energy cost of locomotion is associated with reductions in daily total energy expenditure (TEE) and physical activity; reduced physical activity will be associated with increased adiposity. The study population consists of 375 male and female children ages 6 to 20: 90 MM, 45 SCI, 120 CP, 30 DMD, and 90 controls. Measurements include: 1) anthropometrics, 2) whole body and regional body composition by dual-energy x-ray absorptiometry (DXA), 3) quantitative isometric and isokinetic strength at the elbow and knee, 4) resting metabolic rate (RMR) by indirect calorimetry, 5) energy cost of ambulation and/or wheelchair locomotion (ml O2/Kg meter and Kcal/Kg meter) via a portable telemetric metabolic, measurement system, and 6) TEE and physical activity index (TEE/RMR ratio) by continuous three day heart rate (HR) monitoring. The energy cost of locomotion will be accessed at baseline and with added weight via a pelvic belt equivalent to a 10% increase in % body fat and a 20% increase in % body fat. We will determine the relative importance of weakness and decreased ratio of lean tissue to total body mass in producing increased energy cost of locomotion, reduced physical activity (as evidenced by the TEE:RMR ratio) and a risk of increased adiposity for disabled children. Objective measures of both energy economy of locomotion and physical activity are functionally relevant outcomes. Establishment of a relationship of both impaired strength and increased adiposity to increased energy cost, and hence, reduced physical activity, will provide a basis for varied interventions to improve functional mobility. Outcome studies assessing interventions directed at improving the energy efficiency of locomotion will need to also consider body composition changes over time if there are indeed significant incremental energy costs during locomotion associated with increased adiposity.