TESTOSTERONE THRESHOLD LEVELS AND LEAN TISSUE MASS TARGETS NEEDED

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 背景技术背景：在HORMA（衰老中肌肉和代谢的激素调节剂）试验中，补充睾酮和重组人生长激素（rhGH）增强了瘦体重、骨骼肌质量、肌肉性能和身体功能，但结果存在很大的个体间差异。方法：112名65-90岁的男性在双盲2 - 3析因设计中接受睾酮凝胶（5 g/d vs 10 g/d，通过Leydig细胞钳夹）和rhGH（0 vs 3 vs 5 μ g/kg/d）治疗16周。结果包括双能X线吸收法测量的瘦组织质量、一次重复最大力量、Margaria楼梯功率和活动问卷。我们使用通路分析来确定激素水平、肌肉质量、力量和功能变化之间的关系。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. BACKGROUND: In the HORMA (Hormonal Regulators of Muscle and Metabolism in Aging) Trial, supplemental testosterone and recombinant human growth hormone (rhGH) enhanced lean body mass, appendicular skeletal muscle mass, muscle performance, and physical function, but there was substantial interindividual variability in outcomes. METHODS: One hundred and twelve men aged 65-90 years received testosterone gel (5 g/d vs 10 g/d via Leydig cell clamp) and rhGH (0 vs 3 vs 5 ¿g/kg/d) in a double-masked 2 ¿ 3 factorial design for 16 weeks. Outcomes included lean tissue mass by dual energy x-ray absorptiometry, one-repetition maximum strength, Margaria stair power, and activity questionnaires. We used pathway analysis to determine the relationship between changes in hormone levels, muscle mass, strength, and function.