The group of more than 600 different muscle in human body in synchrony to make the body shape

The group of more than 600 different muscle in human body in synchrony to make the body shape, function, store energy, move in all the directions necessary for accomplish all daily activities.
The muscular system is needed for all other system in the body to work, the only way for the body to function correctly is to have all system work properly as well.
As the other parts of the body the muscular system use as source of energy to function proteins, nutrients, and oxygen making it possible to make movements. The circulatory system transport those needed particle provided by the digestive system and respiratory system.
The smooth, cardiac, and skeletal are the three different muscle tissues that form the muscular system. The skin, internal organs, reproductive system, major blood vessels, and excretory system are compose by the smooth muscle formed by spindle-shaped cells. Muscles attached to more than one bone by tendons are the long fibers surrounded by sarcolemma skeletal muscles, which are voluntary muscles, responsible for speech, facial expression, and move the body. The cardiac as the name already hint is the heart muscle.
Muscle will contract and relax to coordinate and make the body move, only by coordinating with right precision the movement of the body is possible, a muscle is always pulling and relaxing, there might an impression of a pushing but that is not really a function of the muscle.
Cardiac is an involuntary muscle and will not need to be stimulated to react.