From little movements like blinking to larger ones like running, the muscular system is responsible for every single movement in your body. While you control some muscles voluntarily, others do their jobs without having to think about it, allowing you to move, speak, chew, breathe, digest and more. Here are eight other facts about the system that keeps you going.
1. How many? Your body contains more than 600 muscles, from the ones you can actually feel, like your biceps, to the ones that keep your heart beating.
2. Type breakdown. There are three types of muscles in the body: skeletal, which are attached to bones and care consciously controlled; smooth, which are inside of blood vessels and organs, and cannot be voluntarily controlled; and cardiac, which are located in the heart and responsible for pumping blood.
3. Scaling it. Muscle makes up approximately 40% of total body weight. A cubic inch of muscle weighs three times more than a cubic inch of fat.
4. Biggest to smallest. The largest muscle in the body is the gluteus maximus and the tiniest are located in the inner ear, called tensor tympani and stapedius.
5. Strength matters. Based on its size, the strongest muscle in the body is called the masseter, which is located in your jaw and allows you to chew. But, the hardest working muscle is the heart, which pumps about 2,500 gallons of blood daily.
6. Opposites control. The motor cortex on the right side of the brain controls the muscles on the left side of the body, and the motor cortex on the left side controls the muscles on the right side of the body.
7. Natural thermometer. One important function of the muscular system is maintaining normal body temperature. Almost 85% of the heat a person generates in their body comes from contracting muscles. The skeletal muscles increase their activity (think shivering) to make heat if the body heat falls below an optimal level.
8. Get connected. Tendons are a connect tissue that connect muscles to bones in the body.