Muscle Loss Aging Osteoarthritis Sarcopenia

"From about age 30, the density of bones begins to diminish in men and women; this loss of density accelerates in women after menopause. As a result, the bones become more fragile and are more likely to break, especially 'as we become older.]

"As people age, their joints are affected by changes in cartilage and in connective tissue. The cartilage inside a joint becomes thinner; components of the cartilage ...become altered, which may make the joint less resilient and more susceptible to damage. Thus, in some people, the surfaces of the joint do not slide as well over each other as they used to. This process may lead to osteoarthritis...

"Sarcopenia is a process throughout life. Additionally, joints become stiffer because the connective tissue within ligaments and tendons becomes more rigid and brittle...

Sarcopenia is a fancy word for muscle loss. "...'It] starts around the age of 30 and progresses throughout life...the amount of muscle tissue and the number and size of muscle fibers gradually decrease. The result of sarcopenia is a gradual loss of muscle mass and muscle strength. Fortunately...'this] can be partially be overcome or at least significantly delayed by regular exercise..." Emphases added.

From The Merck Manual, 2003, edited by Mark H. Beers, M.D.