NSCA CPT H1

... produces the force to move and ... directs and controls the voluntary movement (thought through action)

Lies outside the central nervous system and relays nerve impulses

Responsible for activating skeletal muscles

Controls involuntary functions (contraction of the heart)

Contains specialized muscle fibers (intrafusal fibers) they have contractile proteins at each end (actin and myosin) and central region that is wrapped by sensory nerve endings

Plays a role in protecting the muscle from injury, located at the junction muscle and tendon

2 mechanisms that the nervous system use to vary, grade, force production to accomplish these tasks

... protects organs and attachment to muscle (skull, vertebral, column, sternum and ribs),
... is responsible for movements (bones of lower and upper limbs)

Condition in which the bones become weak

... attaches muscle to bone (collagen) and ... connects bones to other bones (collagen and elastin, ability to stretch, stabilization and mobility)