Two Types of Muscles

Your body has more than 600 muscles that help you move and stay alive. These muscles can be divided into two main groups based on how they work.

The first group is called voluntary muscles. Voluntary muscles are muscles you control on purpose. When you decide to kick a ball, wave to a friend, or write your name, you are using voluntary muscles. The muscles in your arms, legs, and face are voluntary muscles. These are also called skeletal muscles because they are attached to your bones. Think of voluntary muscles like the steering wheel in a car—you decide where they go and what they do.

The second group is called involuntary muscles. Involuntary muscles work automatically without you thinking about them. Automatically means something happens by itself without you having to control it. Your heart is made of involuntary muscle that beats all day and night, even when you sleep. Your stomach has involuntary muscles that squeeze and mix your food to help digest it. You cannot tell your heart to stop beating or your stomach to stop working—they do their jobs automatically.

Your body needs both types of muscles. Voluntary muscles let you run, play, and do activities you enjoy. Involuntary muscles keep you alive by making your heart beat, helping you breathe, and digesting your food. Both types work together to keep your body healthy and active.

Interesting Fact: Your heart is the hardest-working involuntary muscle in your body—it beats about 100,000 times every single day!