Ageing is associated with reduced margins and impairments in several physiological systems including increase in body fat and a decline in lean mass called sarcopenia and limiting physical abilities. Disease Related Malnutrition (DRM) becomes prevalent due to increased risk to develop chronic disease by age. To prevent and reduce the loss of muscle mass and function physical activity and nutrition are of importance. The evidence for a combination effect is convincing. Except adequate energy intake protein and vitamin D are of specific importance to maintain muscle mass. Some amino acids seem of key importance. A major cause of sarcopenia is inactivity and anabolic resistance. Physical exercise, mainly resistance training has been shown to be of significant importance for muscle protein synthesis. Adequate muscular function is a prerequisite for independence and quality of life. It is urgent to learn more about how to prevent and treat loss of muscle mass and function in ageing.