It’s often easy to overlook the effect that exercise has on the skeletal system because our bones and other associated skeletal organs are very much out of sight and out of mind. The skeletal system consists of our bones, ligaments which connect bones to other bones and cartilage which protects our bones from wear and tear. Exercise has a number of effects on our skeletal system both in the short and long term.
Increased Synovial Fluid Production
Our bones and joints are avascular, that is to say they have little or no blood supply. To keep our joints healthy, stop our cartilage from drying out and keep our cartilage lubricated and nourished, our joints produce an oil-like substance called synovial fluid. Synovial fluid is produced by the synovial membrane within our joints and is a short term or acute response to exercise. This means that our joints require regular exercise to stay lubricated, nourished and healthy.
Increased Joint Range of Movement
Exercise increases the production of synovial fluid which keeps our joints lubricated and makes them supple. Synovial fluid production increases the range of movement available at your joints in the short term. Often, after long periods of immobility, our joints “dry out”, stiffen up and lose some of their movement range. Exercise increases the range of movement available at our joints as more lubricating synovial fluid is released into them. Mobility exercises such as arm circles and knee bends keep our joints supple by ensuring a steady supply of synovial fluid.
Increased Bone Density
Weight-bearing exercise such as strength training and running put stress through your bones. In response to this stress our bodies produce cells called osteoblasts which build new bone and make our bones stronger and denser. Increased bone density can prevent a condition called osteoporosis which is the weakening of bone and an increased likelihood of suffering fractures. Osteoporosis is more common in older females but can affect either sex at any age.
Our bones are held together with non-elastic avascular strap or cord-like structures called ligaments. Without ligaments, our joints would be very unstable and would probably bend the wrong way! When exposed to regular exercise, ligaments will become stronger and more resistant to injury. Because ligaments have no or a very poor blood supply, any adaptations are very slow to develop.