[Influence of nutrition and physical activity on muscle in the very elderly]

AGE-RELATED LOSS IN MUSCLE MASS: Aging is associated with a progressive decline in muscle mass (sarcopenia). Age-related sarcopenia results in a 50% decrease in muscle fiber area, especially type II fiber area. There are many consequences related to this reduction in muscle mass including decline in muscle strength and function and impaired functional capacity. PROTEIN INTAKE: Sarcopenia also results in a reduction in the body's major protein pool. Adequate dietary protein to replace obligatory nitrogen loss and to support protein turnover is essential for maintaining muscle mass. It is usually suggested that protein requirements in older subjects are above 1 g/kg/d. PHYSICAL EXERCISE: Sedentary lifestyle may contribute to loss of skeletal mass in elderly people. Exercise can help reverse this deficit and may improve the regeneration potential of muscle fibers.