The main function of the muscular system is to facilitate movement of the body and maintain posture. This system is composed of skeletal, smooth, and cardiac muscles, which work together to generate force and allow a wide range of motions. Skeletal muscles, attached to bones, enable voluntary movements, while smooth muscles control involuntary functions in organs and blood vessels. Cardiac muscle, found only in the heart, is responsible for pumping blood throughout the body. The muscular system also helps regulate body temperature through heat production when muscles contract during physical activity.