EXERCISE, NUTRITION, AND SARCOPENIA IN OLDER ADULTS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 营养和阻力运动训练可以在维持和增加老年人的肌肉质量有用。 然而，一些研究表明，当碳水化合物与蛋白质一起摄入时，老年人的肌肉蛋白质合成可能会减弱，而当氨基酸单独摄入时，合成是正常的。 具体目标是： 1)为了确定哪些信号通路负责与混合膳食（蛋白质和糖）摄入在衰老过程中的肌肉蛋白质合成的钝化反应。 2)确定12周的水基运动训练计划（利用有氧运动和阻力运动）是否会恢复老年受试者摄入混合餐（蛋白质和糖）的反应。 在18-40岁的年轻健康男性和女性以及60-85岁的老年健康男性和女性中，我们将测量摄入蛋白质和糖的反应。然后，老年受试者将进行为期12周的水基运动，每周3次，每次1小时。然后，我们将测量老年受试者在12周的水中运动后对摄入蛋白质和糖的反应。 我们将测量所有受试者在休息时和摄入蛋白质和糖溶液后的信号通路（mTOR）和肌肉蛋白质合成的分数合成率。在老年受试者中，我们还将测量他们在整个研究期间吃的食物类型和数量。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Nutrition and resistance exercise training can be useful in maintaining and increasing muscle mass in the elderly. However, some studies suggest that when carbohydrates are ingested with protein, muscle protein synthesis may be blunted in older individuals whereas when the amino acids are ingested alone, synthesis is normal. The specific aims are: 1) To determine which signaling pathways are responsible for the blunted response of muscle protein synthesis associated with mixed meal (protein and sugar) ingestion in aging. 2) To determine if a 12-week water-based exercise training program (utilizing both aerobic and resistance exercises) will restore the response of mixed meal (protein and sugar) ingestion in older subjects. In young healthy males and females between the ages of 18-40 years and older healthy males and females 60-85 years of age we will measure the response of ingestion protein and sugar. The older subjects will then perform 12 weeks of water based exercise 3 x/week for one hour. We will then measure the older subjects' response to ingesting protein and sugar after the 12 weeks of water exercise. We will measure the signaling pathways (mTOR) and fractional synthetic rate of muscle protein synthesis in all subjects at rest and after ingesting the protein and sugar solution. In the older subjects we will also measure the type and amount of food they eat throughout the study period.