Muscles
⭐ MasteredMuscles pull on bones to make you move. They work in pairs: when one contracts, the other relaxes.
The strongest muscle for its size is the masseter in your jaw.
All about Muscles
Muscles are tissues that contract, or shorten, to create movement. Most muscles are attached to bones by tough cords called tendons. When a muscle contracts, it pulls on the bone and the body part moves.
Muscles usually work in pairs. The biceps bends the elbow, while the triceps straightens it. When one muscle contracts, the other relaxes. Your body has over 600 muscles, including the heart, which is a special kind of muscle.
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Real-life uses of Muscles
- Lifting your arm to wave or catch a ball
- Smiling and blinking with facial muscles
- Pumping blood with the heart muscle
Frequently asked questions about Muscles
How many muscles are in the body?
The human body has more than 600 muscles. Your largest is the gluteus maximus in your bottom.
Why do muscles get sore after exercise?
Tiny tears in the muscle fibres cause soreness, and they repair themselves, making the muscles stronger.
Are muscles made of fat?
No. Muscles are made of protein fibres. Exercise builds and strengthens them.