Muscle mass peaks at about 30 years of age; it then decreases 3–8% per decade, this loss accelerates after 60 years of age. Loss of muscle mass and loss of strength is termed sarcopenia and is associated with increased risk of functional impairment (walking 3-4 blocks) and physical disability (difficulty performing activities of daily living). Approximately 35% of older adults have moderate sarcopenia and 10% have severe sarcopenia. Fortunately, resistance training exercises can improve muscle mass, strength and physical function.