EXERCISE AND CALCIUM EFFECT ON PUBERTAL BONE GAIN

描述(改编自申请者S描述)：骨质疏松症是一种主要的 公共卫生问题。这个应用程序在早期专注于问题 生活。由于几乎没有已知的安全、有效的恢复丢失的方法 对骨质疏松的骨骼来说，预防骨质疏松至关重要。 如果骨骼发育能够在生长过程中最大化，年轻人将 以最佳的骨骼质量进入成年期，不太可能发生 晚年骨质疏松。然而，儿童的骨骼健康并没有得到 得到了充分的解决。这项建议将建立在之前的4项研究的基础上 儿童的骨质量。本申请中的骨骼质量定义为 骨矿含量(BMC)，用密度计法和膝盖骨表观测量法测定 超声速度(Avu)。本实验研究的目的是：1) 测试负重运动计划对骨骼增加的影响 青春期女性从9岁开始的质量；和2)比较 在高钙饮食的作用下进行负重锻炼 和一个负重锻炼计划，以提高骨骼质量 青春期女性从9岁开始。需要检验的主要假设 包括：1)完成3年负重的青春期女性 运动计划将比青春期有更高的脊柱BMC和膝盖骨Avu 保持正常活动水平的女性，2)青春期 完成了为期3年的负重锻炼计划并 每天1500毫克的高钙饮食干预会有更高的脊柱BMC和 完成锻炼计划的青春期女性的髌骨Avu 但仍保持着正常的钙摄入量。方便的114个样本 九岁。年长的女孩将被随机分配到3组中的一组：1)一组 谁将参加一项负重锻炼计划，该计划符合 每周次数和谁将消耗他们通常的饮食；2)谁将是 参加一项负重锻炼计划，每周举行3次， 将给予高钙食物，每天供应1500毫克；或3)对照组 将食用他们通常的饮食并保持他们的习惯的群体 活动级别。脊柱BMC、髌骨Avu、日常饮食的测量 摄入量，身高，体重，晒黑阶段，体力活动，医疗和 社会史将在基线上每三个月对所有科目进行一次， 3年后复查。增加的积极影响的证据 负重运动和/或增加从食物来源的钙摄入量 在骨骼质量之后将提出另一项建议，以确定 治疗队列可以将他们的骨骼优势保持到很晚 青春期。S工作的总体长远目标是检验 旨在有意识地增加钙摄入量的干预措施 和体力活动改善儿童的骨骼健康和发育 终身骨骼健康行为。

DESCRIPTION (Adapted from Applicant s Description): Osteoporosis is a major public health problem. This application focuses on the problem early in life. Since there are few known safe, effective methods for restoring lost bone to the osteoporotic skeleton, prevention of osteoporosis is crucial. If skeletal development can be maximized during growth, young people will begin adulthood with optimal bone quality and be less likely to develop osteoporosis in later years. Yet bone health of children has not been adequately addressed. This proposal will build on 4 previous studies of bone quality in children. Bone quality in this application is defined as bone mineral content (BMC), determined by densitometry and patellar apparent velocity of ultrasound (AVU). The aims of this experimental study are 1) to test the effect of a weight-bearing exercise program on increases in bone quality in pubertal females beginning at age 9; and 2) to compare the effect of a weight-bearing exercise program with the effect of a high-calcium diet and a weight-bearing exercise program on increases in bone quality in pubertal females beginning at age 9. The primary hypotheses to be tested are: 1) Pubertal females who have completed a 3-year weight bearing exercise program will have higher spine BMC and patellar AVU than pubertal females who have maintained their usual activity level, and 2) pubertal females who have completed a 3-year weight-bearing exercise program and a high calcium diet intervention of 1500 mg/day will have higher spine BMC and patellar AVU than pubertal females who have completed the exercise program but have maintained their usual calcium intake. A convenience sample of 114 nine yr. old girls will be randomly assigned to 1 of 3 groups: 1) a group who will be enrolled in a weight-bearing exercise program which meets 3 times/week and who will consume their usual diets; 2) a group who will be enrolled in a weight-bearing exercise program which meets 3 times/week and will be given high calcium foods to supply 1500 mg/day; or 3) a control group who will consume their usual diet and maintain their customary activity level. Measurements of spine BMC, patellar AVU, usual dietary intake, height, weight, Tanner Stage, physical activity, and medical and social history will be made on all subjects at baseline, every three months, and at the end of 3 years. Evidence of a positive effect of increased weight-bearing exercise and/or increased calcium intake from food sources on bone quality will be followed by another proposal to determine if the treatment cohorts can maintain their skeletal advantage into late adolescence. The overall long-term aim of the P.I.'s work is to test interventions designed to bring about conscious increases in calcium intake and physical activity in children to improve their bone health and develop lifelong bone healthy behaviors.