A

Locomotion

The nervous system controls the muscles

Spinal chord with neural ramifications

What does the brain have to do with the muscle?
When you think about moving your leg, your brain is the one that sends a signal through the nervous cells to the muscle, commanding it to have contractions. The brain controls every movement.

24h monitoring.
The brain supervises what happens in the body and sends messages through the spinal chord and the nerves. While different parts of the body send signals back to the brain informing their status. Always!

This feedback to the brain includes important feelings, such as pressure, warmth, cold movement and pain.

B

Actin and myosin are molecules responsible for the contraction of muscles.

What are the muscles?
They are part of the “engine” that your body uses to move. The basic action of muscles is their contraction, and for that, they need energy.

How many types of fibers are there in the muscles?
There are two types of fibers in the muscle: the ones of fast contraction and the ones of slow contraction. For instance: we mostly use fibers of fast contraction when serving a spike in volleyball (potency); whereas we use the fibers of slow contraction in a marathon (resistance).

C

Biceps muscle of arm (skeletal muscle) with its insertion points

What are and how do the 3 types of muscle work?
Skeletal muscle – It’s connected to the skeleton and contract voluntarily. You think and your nervous system commands. Dancing and running are good examples. The muscles can perform effective skeletal movement from its insertion points.

Insertion point- it’s the place where the muscle is connected to the bone.

Smooth muscle – It’s in the digestive system, in the blood vessels, in the bladder, in the air way and in the uterus, among others. It acts involuntarily and automatically. For example, your stomach and intestine work the whole day without you noticing it.

Cardiac muscle – It exists only in the heart and its characteristic is its resistance. It contracts involuntarily. It can stretch in a limited way, such as the smooth muscle, and contract with the force of a skeletal muscle.

D

Muscles of the lower limbs

How do we move?
Our locomotive system is formed by bones, joints and muscles, which work together. The bones are rigid structures that give support to the body. The muscle is a flexible and resistant tissue that works together with the bones and joints to move our body.

Why do we, in life or death circumstances, have so much strength?
Because our brain sends a command so that our skeletal muscles may develop the maximum force of contraction. At the same time, any other feeling, such as pain, is suppressed.