Final answer:
During middle adulthood, individuals may experience a decline in bone density and deterioration of articular cartilage, leading to increased risks of arthritis and joint pain. Muscle strength and aerobic performance often decline, and common diseases like type 2 diabetes and cardiovascular disease can impact bone and joint health. Changes in weight distribution can also place stress on joints, exacerbating wear and tear.
Step-by-step explanation:
Changes in Joints and Bones During Middle Adulthood
During middle adulthood, which lasts from about the mid-30s to the mid-60s, individuals experience a variety of changes in their joints and bones. Firstly, bone density may start to decline after age 40, particularly in women post-menopause due to osteoporosis. This can lead to a gradual loss of height, up to 1 cm per decade. The articular cartilage, which helps to provide an extremely smooth surface for movement between bones, may begin to deteriorate, contributing to a higher risk for arthritis and joint pain. Additionally, the immune system may attack healthy cells in the lining of joints in certain diseases like rheumatoid arthritis, causing inflammation and further joint pain.
While bones stop growing in length in the late teens to early twenties, they can still increase in thickness if subjected to increased muscle activity or strain. Muscle strength and aerobic performance often start to decline during middle adulthood as well. Diseases such as type 2 diabetes, cardiovascular disease, and cancer may become more common during this stage, which also affect overall health and the body's support systems, including bones and joints.
Moreover, due to decreased physical activity, metabolic changes, or other health conditions, middle-aged adults may experience changes in weight distribution which can place additional stress on the joints, particularly in the hips, knees, and ankles, potentially accelerating wear and tear.