A common effect of aging on muscle mass is the loss of lean muscle known as sarcopenia. This condition often begins around age 30 and accelerates after 60. Hormonal changes, decreased physical activity, and nutritional deficiencies contribute to this decline. The loss of muscle can lead to reduced strength, increased risk of falls, and decreased metabolic rate, which may impact overall health. To counteract these effects, regular strength training and adequate protein intake are essential to maintain muscle mass as one ages.