I get twitches in my muscles like my calf etc how come the same doesnt happen with the heart? all other muscles twitch but never heart?

Heart is smooth musc: The legsare striated muscle and the heart is smooth muscle. this may help explain some of the differences. Leg cramps are a common and usually harmless condition where the muscles in your leg suddenly become tight and painful. It usually occurs in the calf muscles, although it can affect any part of your leg, including your feet and thighs. After the cramping has passed, you may have pain and tenderness in your leg for several hours. Three out of four cases occur at night during sleep.