PROTEIN, ENERGY AND EXERCISE EFFECTS ON SENESCENT MUSCLE

这些研究旨在研究饮食蛋白质的影响。 整体和部分蛋白质的合成与蛋白质的积累 高强度渐进性抵抗过程中的骨骼肌群 培训(PRT)计划。之前的研究已经证明，年龄较大的人 男性和女性都保持着增加肌肉力量和 体型是对胎龄的反应，甚至到了生命的第十个十年。我们的 研究还表明，对运动的代谢反应， 尤其是涉及离奇运动的运动，是相当 年老的和年轻的受试者不同。与年轻、年长的人相比 受试者的肌肉损伤量越大， 肌纤维蛋白分解，中性粒细胞减少，循环 肌酸激酶活性。我们还展示了常规的 运动增加了对膳食蛋白质和膳食补充剂的需求 将有利于老年男性肌肉质量的增加。这项研究领先于 我们同意这样一种假设，即在高潮期间增加饮食蛋白质 强度的PRT会增加肌肉蛋白质的合成，增加 肥厚率。年长的男性和女性将食用无糖饮食 提供0.8或1.6g的蛋白质RDA，为期3个月。阶梯状 氮平衡与持续的1-13C-亮氨酸输注 将使我们能够检查全身的氨基酸动力学和 将该标记结合到骨骼肌中以确定效果 日粮、年龄和PRT对肌肉蛋白质合成速率的影响。我们 已经表明，计算机断层扫描和活组织检查分析 灵敏的工具来检查肌肉肥大的速度。这些 这将是第一个研究饮食蛋白质对健康的影响 肌肉的新陈代谢，大小和力量将在一个严密的 新陈代谢控制病房。这项研究提供了一个机会 检测老年人RDA蛋白的充分性及其影响 氮素滞留的训练。这些研究将使我们能够 为老年人提供特别的营养建议 并继续进行力量训练计划。

These studies are designed to study the influences of dietary protein on the whole body and fractional protein synthesis and the accretion of skeletal muscle mass during a high intensity progressive resistance training (PRT) program. Previous studies have demonstrated that older men and women retain the capacity to increase both muscle strength and size in response to PRT, even into the tenth decade of life. Our studies have also demonstrated that the metabolic response to exercise, particularly exercise that involves eccentric exercise, is quite different between old and young subjects. Compared to young, older subjects experience greater amounts of muscle damage, greater myofibillar protein breakdown, decreased neutrophilia and circulating creatine kinase activity. We have also demonstrated that regular exercise increases the need for dietary protein and a dietary supplement will favor the accretion of muscle mass in older men. This study leads us to the hypothesis that increased dietary protein during a high intensity PRT will increase muscle protein synthesisand increase the rate of hypertrophy. Older men and women will consume a eucaloric diet providing the protein RDA of 0.8 or 1.6g for three months. Factoral nitrogen balance along with constant, primed infusion of 1-13C-leucine will allow us to examine whole body amino acid kinetics and incorporation of the label into skeletal muscle to determine the effects of the diet, age, and PRT on the rate of muscle protein synthesis. We have shown that computerized tomography and biopsy analysis are very sensitive tools to examine the rate of muscle hypertrophy. These studies will be the first in which the effects of dietary protein on muscle metabolism, size and strength will be examined in a tightly controlled metabolic ward. This study provides an opportunity to examine the adequacy of the protein RDA in the elderly and the influence of training of N retention. These studies will allow us to make specific nutritional recommendations for the elderly as they initiate and continue with a strength training program.