EXERCISE DOSE FOR CARDIOVASCULAR HEALTH OF OBESE YOUTHS

描述：拟议研究的长期目标是 确定心血管(CV)健康的最佳运动量。这个 具体目标是检验两个假设：(1)8个月的体育锻炼 (2)高强度PT将促进肥胖青少年的心血管健康 比低强度PT更有效。13-16岁肥胖儿童(n=180) 随机，在性别和种族(黑人/白人)内，进入对照，低 强度组和高强度组。所有小组都将接受标准护理 (即饮食和运动信息)，PT组接收 此外，还控制了PT。主要结果变量将是脂肪百分比 (用双X射线吸光度测量法测量)。静息代谢、饮食和 将测量自由生活的体力活动(使用双重标记的水)。 一套全面的冠心病(CHD)危险因素将是 评估，包括内脏脂肪组织(磁共振检查 成像)和左心室大小(超声心动图)。 将测量自我概念和自我效能感，以获得对 干预措施的心理影响。心率将保持在低水平 (110-130 bpm)或高强度区(160-180 bpm)，能源消耗 保持不变。这些假设将用来自所有受试者的数据进行检验， 不管是否遵守规定的养生法。后测将是 在最后一次PT会议后的第二天上午，以确定PT的影响 在经常锻炼的肥胖青年中。以确定长期影响 在干预措施中，将在8个月内进行完整的评估 在干预措施终止后。这项研究将提供明确的 关于运动对肥胖青年的影响的数据。此信息 将为青少年治疗方案的发展做出贡献 肥胖，对冠心病一级预防的影响。

DESCRIPTION: The long-term objective of the proposed research is to establish the optimal dose of exercise for cardiovascular (CV) health. The specific aims are to test two hypotheses: (1) 8 months of physical training (PT) will enhance CV health of obese youths, (2) high intensity PT will be more effective than low intensity PT. Obese 13-16 year olds (n=180) will be randomized, within gender and ethnicity (black/white), into control, low intensity and high intensity groups. All groups will receive standard care (i.e. diet and exercise information), with the PT groups receiving controlled PT in addition. The primary outcome variable will be percent fat (measured with dual x-ray absorptiometry). Resting metabolism, diet and free-living physical activity (with doubly labeled water) will be measured. A comprehensive set of risk factors for coronary heart disease (CHD) will be assessed, including visceral adipose tissue (with magnetic resonance imaging) and left ventricular dimensions (with echocardiography). Self-concept and self-efficacy will be measured to gain insight into psychologic effects of the interventions. Heart rates will be kept in low (110-130 bpm) or high (160-180 bpm) intensity zones, with energy expended held constant. The hypotheses will be tested with data from all subjects, regardless of adherence to the prescribed regimens. The post-test will be on the morning following the last PT session to determine the impact of PT in obese youths who exercise regularly. To determine the longer-term effect of the interventions, a complete set of assessments will be made 8 months after termination of the interventions. This study will provide definitive data concerning the effect of exercise in obese youths. This information will contribute to the development of programs for treatment of adolescent obesity, with implications for primary prevention of CHD.