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The Muscular System: What does it do for us?
Muscles are the only tissue in our body that have the ability to contract; we would not be able to move if muscles didn't do that. Skeletal muscles are attached to the bones while other muscles — such as the muscles in our face — are attached to the skin.
Because muscles move our bones, an obvious secondary function of muscles is to help us maintain posture and body position.
How many muscles we have is still up for discussion. There are anywhere between 650 and 840 skeletal muscles, depending on your source.
How many kinds of muscle are there?
There are three types of muscle tissue:
- We can see and feel Skeletal muscle. When you lift weights to increase muscle mass, skeletal muscle is what is being exercised.Their name tells you that they attach to the skeleton; they come in pairs — one muscle to move the bone in one direction and another to move it back. They contract because you think about moving them — and then the nervous system helps you by sending signals to the muscles. Contractions can be short and quick, long and held — or anywhere in between.
- Smooth (or visceral) muscle is found in your digestive system, blood vessels, bladder, and airways. These muscles can stretch and maintain tension for long periods of time. They do their work automatically with only the assistance of the nervous system. For example, the muscles in your stomach and intestines are working all the time.
- Cardiac muscle is found (of course) only in your heart. They have several attributres: strength, endurance, consistency. They also work involuntarily — and that's a good thing.
Muscles are complex in their structure and, as you can see, quite different from one type to another.
What are some disorders of the muscle system?
Because of its complexity, it's not surprising that the muscular system can have many things go wrong with it. Some conditions are genetic; others are acquired. Some are complex, while others are relatively simple. There are treatments for some; others are progressive.
Here's a list of some of the diseases or disorders of the muscular system (listed in alphabetical order):
Cerebral Palsy: This is a very common congenital disorder that affects the posture, balance and motor functions. Physical tasks become more difficult as the disease progresses.
Compartment Syndrome: As its name implies, in this syndrome, blood vessels, muscles and nerves get compressed into a closed area. Oxygen supply is cut off and then tissue death can occur. This can lead to paralysis.
Dermatomyositis: This autoimmune disease harms connective tissue, resulting in weakened muscles.
Fibrodysplasia Ossificans Progressiva: Over time, soft tissue hardens and becomes bone-like. Bone can even grow between joints; as a result, movements become permanently restricted.
Fibromyalgia: This is a chronic and debilitating genetic muscle disorder. It causes pain, fatigue, tenderness and stiffness of muscles.
Lou Gehrig’s Disease: Named after the baseball player who got this disease, it is a slow, progressive condition which eventually leads to paralysis. Early symptoms include difficulty in breathing, speaking and swallowing. (Also known as Amyotrophic Lateral Sclerosis).
Mitochondrial Myopathies: This results in weakness of muscles, deafness, blindness, arrhythmia and heart failure. Sometimes it can cause seizures, dementia, vomiting and droopy eyelids.
Muscular Dystrophy: This is a genetic disease in which damage occurs to muscle fibre. Symptoms include weakness, immobility and imbalance.
Myasthenia Gravis: In this autoimmune disease, the brain loses control over the muscles, resulting in weak muscles and fatigue. Symptoms may include drooping eyelids, as well as general loss of facial muscle control. There may also be difficulty in breathing or swallowing.
Myofascial Pain Syndrome: As the name implies, this condition causes aching and burning sensations in the muscles. Unsurpisingly, joints get stiff and muscles feel as though they have "knots" in them. Sleep can be difficult due to the pain.
Myotonia: The muscles relax very slowly after they have contracted; as a result, problems arise when one releases their grip on an object or after sitting or sleeping for a long time.
Polymyositis: Degenerative and inflammatory. It causes extreme muscle weakness and the muscles atrophy.
Rhabdomyolysis: Skeletal muscle is quickly destroyed in this condition. As the fibers break down, muscle weakness, pain and stiffness occur.
Some injuries of the muscular system include:
Rotator Cuff Tear: A very strong joint, the muscles of the shoulder joint rotate the shoulder and help to move the hand front and back. A rotator cuff tear happens during rigorous, fast movements, like that in baseball or tennis. Once the tear occurs, there is pain and reduced mobility. (See also: Common Injuries of the Shoulder and Knee)
Muscle Cramps: Muscle cramps can occur any time, several at a time or just one alone. They can last for seconds or up to several minutes. It can be caused by a variety of reasons, such as overusing a muscle or pinching a nerve. As well, some medications may cause cramping. (See also: Muscle Cramps and Other Injuries)
Sprains and Strains: When we twist or pull muscles or tendons, we may develop a sprain or strain. This can happen suddenly, or over a period of time. There may be pain, swelling, and some difficulty of movement. It is wise to rest a sprain or strain; ice compresses may help.
Tendonitis: Although tendonitis can occur in any tendon, it is most common in wrists, elbows, shoulders, and heels. The tendon gets inflamed or irritated. It can be very painful, there may be mild swelling and tenderness. Pain relievers, rest and ice compresses may help, but rest is certainly advised.
How can we take care of our muscular system?
Muscles turn energy into motion — similar to a car engine. It would be impossible for you to do anything without your muscles. Unfortunately, we have a tendency to take them for granted and only really notice them when they don't work.
Research abounds with the evidence that working our muscles will keep them healthier and give us greater quality of life. At the same time, they can be injured easily, so we must be cautious about how we work our muscles. If you have never done weight training, it is advisable to seek professional advice (a personal trainer or a fitness class with a qualified fitness instructor). For a bit more detail on the benefits of weight training, see Why Lift Weights?.
See also (articles about individual muscles, what they do, how they work, and exercises for them):
- The Abdominals
- The Adductors
- Common Injuries of the Shoulder and Knee
- The Deltoids
- The Erector Spinae: Spine Muscles
- The Forearm, Elbow, and Wrist
- The Glutes
- The Hamstrings: Back of the Thigh
- The Hip Flexors
- Latissimus Dorsi: The Lats
- The Lower Leg: The Calf and the Shin
- Muscle Cramps and Other Injuries
- Muscles of the Head
- Opposing Muscles
- Pectoralis Major and Minor: The Pecs
- The Quadriceps: The Front of the Thigh
- Taking Care of your Feet
- The Trapezius and the Rhomboids
- The Upper Arm: The Biceps and the Triceps
I am a BCRPA-certified fitness instructor in Vancouver, BC. I teach four classes at the West End Community Centre in Vancouver, BC, mostly designed for the older adult. The Inevitable Disclaimer: Everything published here expresses only my opinion, based on my training and research. What you do with the information is entirely your own responsibility. I am not liable for any injury you suffer that seems to be related to anything you read here. Always consult your doctor before beginning an exercise program. For other articles, return to the table of contents.
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