During ageing joint movement becomes stiffer and less flexible due to inflammation and a reduction in synovial fluid and cartilage. Reduced flexibility of the ligaments can also make the joint feel stiffer.
Arthritis or osteoarthritis is the chronic degeneration of the cartilage at the ends of bones and a reduction in fluid in the joint capsule leading to pain, swelling and stiffness. It most commonly affects hip and knee joints and is thought of as a wear and tear condition.
Joint lubrication with synovial fluid
The best analogy for synovial fluid in the joint capsule is like oil in a car engine. A well-oiled engine runs smoother. Movement creates more synovial fluid allowing your bones to move around one another more freely, thus more movement breeds easier movement.
Stretching exercises help to improve flexibility of the ligaments in the joints and surrounding muscles. This eases the stiffness in the joint and can keep each joint moving properly.
Muscle fibers tear when a muscle is exercises, but during the repair process the muscle is strengthened. Regular tear and repair is how muscles grow and improve in strength, therefore good for muscles. Strong muscles act to protect and brace the joint during movement.
Increased blood flow and nourishment of the joint
Muscle contractions during exercise mean the heart needs to get working to pump oxygenated blood throughout the body to the working muscles including the joints. The joint capsule benefits from the oxygen and other nutrients.
Activation of joint-repair genes
We are not quite sure how yet, but it appears that joint movement switches on genes that are associated with rebuilding cartilage! Be sure to listen to your body as you don’t want to over-do it.