If no muscles in your body moved, you would not remain alive. Your heart is made of cardiac muscle. It beats continuously from about 6 weeks after an egg cell is fertilized until the person dies. Heart rates vary, but on average a human heart beats 60-72 times per minute throughout the person's life. In addition to the heart itself, a group of skeletal muscles form the skeletal-muscle pump. These small muscles help the blood return to the heart through the veins by gently squeezing the veins.
You might be able to keep from moving all of your voluntary skeletal muscles, though it is difficult to remain completely still. Your visceral muscles--the smooth muscles of your digestive tract--while generally moving material through your gut, do have times when they are not active. But you could not stay alive if no muscles at all move due to the necessity of having your heart pump blood.
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