Muscles are all made of the same stuff, consisting of thousands or even tens of thousands of elastic tissue fibres, that bind together to make up the muscle. There are more than 600 muscles in the human body and together they form the engine that propels up forwards, backwards and in every other movement we make. They also help us breathe, talk, close our eyes and enable us to carry out every task we are a capable of making.
In the body, there are three types of muscles:
- Smooth muscle
- Cardiac muscle
- Skeletal muscle.
Smooth muscles are just that, and are made up of layers or sheets of muscle, one behind the other. These are involuntary muscles as they perform tasks that we do not have to think about as the brain does it automatically.
Smooth muscles allow the passage of food through your digestive system, they cause your eyes to focus on objects, and they allow us to go to the toilet. When the smooth muscles contract in the bladder, urine is forced out of the bladder and we get rid of the waste products our body produces.
As the name suggests, cardiac muscles make up the heart, which pumps the blood around the body giving our muscles the oxygen they need. When the cardiac muscle contracts, it forces blood away from the heart and out to the body, and when it relaxes, it allows blood to flow to the heart. Similar to smooth muscles, cardiac muscles perform automatically so we do not have to think about them and the job that they do.
Skeletal muscles are those most people are familiar with and allow us to move. Most people associate muscles with the biceps, which are skeletal muscles in the upper arm. Skeletal muscles are voluntary muscles, which mean we can control what they do, such as curling a dumbbell in a gym.
Together with the skeleton, muscles make up the musculoskeletal system, which gives our body’s power and strength. In most cases, a skeletal muscle stretches all the way across a joint and re-attaches to another bone, held in place by tendons. Tendons keep our muscles attached to our bones so when we move our muscles, the bone follows it, such as when we lift our arms.
Some muscles work in pairs such as the triceps and biceps. These two muscles are found in the upper arm so if we bend our arms at the elbow as if flexing our biceps, the bicep muscle contracts while the triceps muscle relaxes. If the arm is then straightened, the bicep now relaxes while the triceps contracts.
- Deltoids – In three parts, the deltoids are the shoulder muscles and allow you to move your shoulders in all directions
- Pectorals – In the upper chest which allow pressing movements such as press ups
- Abdominals – Your stomach muscles found under the rib cage give us our posture and keep us upright and stable
- Bicep and Triceps – Allow us to move our arms, found in the upper arm
- Quadriceps – At the front of the thighs allow extension and retraction of the legs
- Latissimus Dorsi – On our upper back, these muscles allow pulling movements.
Muscles and exercise
When we exercise, whether it is lifting weights, running up hills or cycling, we are using our muscles and the because of this, the muscle is damaged.
As previously said, muscle is made up of thousands of tiny fibres and some of these will break; how many depends on how hard we exercise, and is responsible for making our muscles feel sore. After exercise when we are resting, the muscle repairs itself in such a way that it learns to cope with the stress of the next exercise session, so it becomes slightly stronger than it was before. This process is repeated after each time we exercise which explains why we can become stronger through regular exercise, and why rest is such an important part of any fitness training routine.