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LET'S EXPLORE The human body

What are muscles for?

A gymnast using her muscles to balanceA gymnast using her muscles to balanceYou use your muscles to move your bones—and thus your body—into different positions. This allows you to walk, stand, jump, pick things up, smile and perform many other actions. These types of muscle are called the skeletal muscles. Other types of muscle keep your heart beating and other organs working. You can make your muscles stronger by exercising, or practising movements.

The muscles of the human bodyThe muscles of the human body

Types of muscle

Your body has more than 640 muscles. They form about one third of your whole body weight. Strong, rope-like parts called tendons connect the muscles to bones. A special type of muscle, called smooth muscle, forces food along your oesophagus, stomach and intestines. Your heart is made of another special muscle that beats constantly and never gets tired.


Muscles make up more than 40% of a young person's body weight.
