How your muscles work?
Muscles are how we move and live. All movement in the body is controlled by muscles. Some muscles work without us thinking, like our heart beating, while other muscles are controlled by our thoughts and allow us to do stuff and move around. All of our muscles together make up the body’s muscular system.
There are over 650 muscles in the human body. They are under our skin and cover our bones. Muscles often work together to help us move. We don’t really have to think about moving each individual muscle. For example, we just think of running and our body does the rest.
How Muscles Work
Muscles work by expanding and contracting. Muscles have long, thin cells that are grouped into bundles. When a muscle fiber gets a signal from its nerve, proteins and chemicals release energy to either contract the muscle or relax it. When the muscle contracts, this pulls the bones it’s connected to closer together.
Many of our muscles come in pairs. An example of this is the biceps and triceps in our arms. When the biceps contract the triceps will relax, this allows our arm to bend. When we want to straighten our arm back out, the biceps will relax and the triceps will contract. Muscle pairs allow us to move back and forth.
Types of Muscles
– These are the muscles we use to move around. They cover our skeleton and move our bones. Sometimes they are called striped muscles because they come in long dark and light bands of fibers and look striped. These muscles are voluntary because we control them directly with signals from our brains.
– Smooth muscles are special muscles that don’t connect to bones, but control organs within our body. These muscles work without us having to think about them.
– This is a special muscle that pumps our heart and blood through our body.
Tendons connect muscles to bones. Tendons help form a connection between soft contracting muscle cells to hard bone cells.