PHYSIOLOGY OF AGING

生理系统中年龄变化的研究在 运动(V02峰值)和肾功能(肌酐清除) 骨矿动态平衡参数(离子钙、磷、 维生素D代谢物和甲状旁腺素)和骨密度的测量 (BMD)(单光子和双光子吸收法)。没有独立的 运动水平对运动测试的影响 生化参数或髋部、脊柱或前臂的骨密度水平， 由于年龄的原因，超过了这一点。多元回归证明了这一点。 分析比较两组各参数和BMD均值 正常人口的一部分，三分之一的人口患有 V02高峰期和三分之一人口的最佳年龄调整表现 经年龄调整后表现最差的。对性能的类似分析 对肾功能的影响也显示出相同的结果。任何生化或骨密度 与肌酐清除量相关的变量也与年龄有关。这个 随着年龄的增加，肾功能的影响不明显。 考虑到这一点。 横截面和纵向分析都表明握力下降 在40岁以后以更快的速度增长。随着年龄的增长，握力 肌肉的退化比年龄相关的肌肉衰退预测的更严重 质量。

Studies on age changes in physiologic systems have related performance in exercise (peak V02), and kidney function (creatinine clearance) to parameters of bone mineral homeostasis (ionized calcium, phosphorous, vitamin D metabolites, and PTH) and to measures of bone mineral density (BMD) (single and dual photon absorptiometry). There were no independent effects of level of performance on exercise testing on either the biochemical parameters or on the level of BMD in the hip, spine or forearm, beyond that due to age. This was demonstrated by multiple regression analysis and by comparing mean values for the parameters and BMD in two parts of the normal population, the third of the population that had the best age-adjusted performance on peak V02 and the third of the population with the worst age-adjusted performance. Similar analyses for performance on kidney function showed the same results. Any biochemical or BMD variable related to creatinine clearance was also related to age. The effect of kidney function was not demonstrable once the age effect was taken into account. Cross-sectional and longitudinal analyses agree that grip strength declines at an accelerating rate after age 40. With advancing age, grip strength deteriorates more than is predicted by the age-related decline in muscle mass.