With human aging, there is a gradual but progressive decline in skeletal muscle tissue, also known as sarcopenia . Sarcopenia is accompanied by a reduced physical performance, the loss of functional capacity, increased risk of falling and increased likelihood of developing chronic metabolic diseases, such as type 2 diabetes and obesity. Eventually this also results in increased hospitalisation and institutionalization of elderly in nursing homes, and high health care costs. Therefore, it is important to investigate approaches to diminish the loss of skeletal muscle mass during aging. To preserve muscle mass, protein intake is important, because it provides the building blocks for muscle tissue: amino acids. Since basal muscle protein synthesis rates do not seem to differ between young and elderly, currently many research groups focus on postprandial muscle protein synthesis. Skeletal muscle protein synthesis has been shown to be highly dependent on protein intake. However, recent data indicate that the muscle protein synthetic response to protein intake is attenuated in the elderly. A blunted postprandial muscle protein synthetic response over a prolonged period might result in diminished muscle protein accretion and could eventually contribute to sarcopenia.