you have just learned that skeletal muscles generate force and produce movement only by contracting, or pulling on body parts. Individual muscles can only pull; they cannot push. yet you know from experience that your arms and legs can push when you want them to. how is this possible?
Skeletal muscles are joined to bones by tough connective tissues called tendons. tendons are attached in such a way that they pull on the bones and make them like levers. the movements of the muscles and joints enable the bones to act as levers. the joint functions as a fulcrum (fixed point around which the lever moves), and the muscles provide the force to move the lever. See figure 38-15. Usually there are several muscles surrounding each joint that pull in different directions.