Nutrition & Exercise to Improve Protein Metabolism & Prevent Sarcopenia in Aging

项目描述/摘要 我们的一般假设是，营养因素和不活动在发展中发挥重要作用， 肌肉减少症因此，包括营养操作和/或锻炼在内的特定年龄的长期干预可能 有助于减少，稳定，甚至逆转肌肉质量和力量随年龄的损失。但此前的 试图通过营养补充来改善老年受试者肌肉质量的研究几乎没有 成功，因为老年人有一种趋势，以补充营养补充剂提供的能量， 减少食物摄入。因此，老年人有效的营养补充剂应该比 相同数量的普通食物，以限制热量含量和最大限度地提高合成代谢效率（合成代谢 效果/能量传递）。 我们的初步数据表明，必需氨基酸是最有效的营养素为急性 刺激肌肉蛋白质增加，长期使用也可以改善老年人肌肉质量 科目此外，不活动是肌肉减少症的另一个可能因素。锻炼不仅增加肌肉 质量和强度，还有能量消耗。因此，运动可以改善肌肉对 通过增加能量需求和食物消耗对老年受试者进行营养补充， 从而实现真正的补充。虽然抗阻运动是最合成代谢的形式 对于体力活动，门诊患者的依从性可能令人失望。有氧运动更多 吸引人，更容易在老年人群中实施。我们的初步数据表明有氧运动 急性增加肌肉蛋白质合成，使肌肉灌注正常化，并减少与年龄相关的胰岛素 肌肉蛋白质的抵抗力。因此，有氧运动可以改善肌肉蛋白质代谢，力量， 功能，甚至质量在老年人，特别是当结合营养干预措施。 我们将在久坐不动的老年受试者中检验以下具体假设： 1.一个高效的营养补充剂将增加，随着治疗时间的延长，肌肉质量和 通过刺激净肌肉蛋白质合成来增强肌肉力量。 2.渐进式有氧训练将通过刺激肌肉蛋白质增加肌肉力量和功能 周转和改善肌肉灌注和肌肉质量。 3.高效的营养补充与渐进式有氧训练相结合， 肌肉质量，力量和功能，比单独的干预，通过添加刺激净 肌肉蛋白质合成，改善肌肉灌注和肌肉质量。 我们的目标是确定可以急剧增加肌肉蛋白质合成的特定干预措施是否也可以 有效地转化为老年久坐者肌肉质量和表现的增加。项目叙述 我们的总体目标是找到简单安全的干预措施来预防和治疗肌肉质量的损失， 老年人的力量和功能。随着年龄的增长，肌肉无力会导致身体虚弱、残疾和丧失功能。 独立，增加了机构和死亡的风险，并大大增加了医疗保健费用。 根据我们的初步数据，我们建议长期营养补充高效， 特定年龄的补充剂和/或耐力训练将增强老年人的肌肉质量，力量和功能。 人通过增加肌肉的生长和质量。

PROJECT DESCRIPTION / ABSTRACT Our general hypothesis is that nutritional factors and inactivity play significant roles in the development of sarcopenia. Thus, age-specific prolonged interventions including nutritional manipulations and/or exercise may help to reduce, stabilize, or even reverse the loss of muscle mass and strength with age. However, previous studies attempting to improve muscle mass in older subjects using nutritional supplementation had little success, due to a trend for elders to compensate for the energy delivered by nutritional supplements with reduced food intake. Therefore, effective nutritional supplements for the elderly should be more anabolic than the same amount of ordinary food, to limit the caloric content and maximize the anabolic efficiency (anabolic effect/energy delivered). Our preliminary data indicate that essential amino acids are the most efficient nutrients for the acute stimulation of muscle protein anabolism, and that long term utilization may also improve muscle mass in older subjects. Additionally, inactivity is another likely contributor to sarcopenia. Exercise increases not only muscle mass and strength, but also energy expenditure. Hence, exercise may improve the response of muscle to nutritional supplementation in older subjects via increased energy requirements and food consumption, thereby allowing for the achievement of true supplementation. Although resistance exercise is the most anabolic form of physical activity, compliance in the outpatient setting may be disappointing. Aerobic exercise is more appealing and easier to implement in the older population. Our preliminary data indicate that aerobic exercise acutely increases muscle protein synthesis, normalizes muscle perfusion, and reduces the age-related insulin resistance of muscle proteins. Thus, aerobic exercise may improve muscle protein metabolism, strength, function and even mass in older people, particularly when combined with nutritional interventions. We will test the following specific hypotheses in older sedentary subjects: 1. A highly efficient nutritional supplement will increase, with prolonged treatment, muscle mass and strength by stimulating net muscle protein synthesis. 2. Progressive aerobic training will increase muscle strength and function by stimulating muscle protein turnover and improving muscle perfusion and muscle quality. 3. The highly efficient nutritional supplementation combined with progressive aerobic training will increase muscle mass, strength, and function more than either intervention alone by additively stimulating net muscle protein synthesis, and improving muscle perfusion and muscle quality. Our goal is to establish if specific interventions that can acutely increase muscle protein synthesis can also effectively translate into increased muscle mass and performance in older sedentary people. PROJECT NARRATIVE Our general goal is to find simple and safe interventions to prevent and treat the loss of muscle mass, strength, and function in older persons. Muscle weakness with aging leads to frailty, disability and loss of independence, increasing the risk of institutionalization and death, and greatly increasing healthcare costs. Based on our preliminary data, we propose that prolonged nutritional supplementation with highly effective, age-specific supplements and/or endurance training will enhance muscle mass, strength and function in older persons by increasing muscle growth and quality.