PHYSIOLOGY OF AGING

生理系统年龄变化的研究， 运动（峰值V02）和肾功能（肌酐清除率）， 骨矿物质稳态参数（离子钙，磷， 维生素D代谢物和PTH）和骨矿物质密度的测量 (BMD)（单光子和双光子吸收测定法）。 没有独立 表现水平对运动测试的影响 生化参数或髋部、脊柱或前臂的BMD水平， 因为年龄的原因。 这一点通过多元回归得到了证明 分析，并通过比较平均值的参数和骨密度在两个 部分正常人群，三分之一的人， 峰值V02和三分之一人群的最佳年龄调整性能 年龄调整后的表现最差 类似的性能分析 对肾功能的影响也是一样的 任何生化或骨密度 与肌酐清除率相关的变量也与年龄相关。 的 一旦年龄效应被证实， 考虑了 横截面和纵向分析一致认为， 在40岁之后加速增长 随着年龄的增长，握力 恶化程度超过了与年龄相关的肌肉衰退所预测的程度 马萨诸塞州

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.