Muscle tone, muscles, musculoskeletal system..

Muscle tone  The natural tautness or laxity of a muscle when it is resting. The ideal tone of a muscle lies between total contraction and total relaxation. Tone allows the body to function properly and enables good coordination, joint function and stability. Muscle performance is dependent on the level of muscle tone.

Muscles (deep stabilizers, shunt muscles)   The muscles which lie closest to a joint. Their main function is to hold the joint together and to ensure that the bones move properly in relation to one another. They function mainly reflexively and do not require conscious thought to work properly.

Muscles (prime movers, spurt muscles)   The muscles which lie closest to the surface and have the greatest mechanical advantage for creating joint motion. Prime movers are under conscious control yet work in concert with deep stabilizers.

Musculoskeletal System   The structural system of the body which allows it to move and maintain its form. It consists of muscles, tendons, ligaments, bones and joints and associated tissues.

Musculoskeletal Disorder (MSD)   Literally a disorder or problem which arises in an area of the musculoskeletal system. Work related MSD's occur when the physical demands of a job exceed the natural capabilities of the body. Symptoms may include, pain, discomfort, inflammation, swelling and limited mobility.

Myelin sheath   The fat and protein-containing material that surrounds and protects some nerves allowing electrical impulses to travel quickly between the brain and other parts of the body.

Myopathy   A category of muscle diseases. There are more than a dozen types of myopathies most of which have symptoms of weakness, cramps, stiffness and spasm. While these symptoms are common to many musculoskeletal disorders which are not myopathies, the presence of these symptoms does not in itself indicate presence of a myopathy.