Skeletal muscles are responsible for body movement and maintaining joint stability.
The body's total muscle mass peaks in the late 20's and begins to decline steadily afterwards. Weakened muscles can contribute to chronic back and joint pain and increased risk of injury from falls. Quality of life is affected by a decreased ability to carry objects, perform household activities, climbing stairs, etc. Like many of the physical aspects of aging, the decline in muscle mass can be slowed down or reversed with regular exercise. Muscles grow stronger when they are regularly worked against increased resistance.