You have more than 600 muscles all over your body, and they are the parts that let you move. Muscles are made of bundles of thin threads called fibres, packed together like a bundle of straws. When your brain sends a signal, the fibres pull on your bones and your body moves. Every smile, jump, and high five is your muscles doing their job.
⚡ DID YOU KNOW?
The strongest muscle for its size is your jaw muscle, and the busiest muscles of all are the tiny ones that move your eyes.