Exercising the Smart Way: Understanding How Muscles Work and What Works Best

Just about every body function that you can think of requires some sort of muscle activity. It is required to move the bones in your skeleton, the muscle of your heart contracting directs the blood around your circulatory system, muscles move food through your esophagus to your stomach, and then moves the waste through your digestive system. Muscles help you to breathe, they help to maintain your posture, and they allow you to pick up and hold things, or even walk out your front door. Think of all the activities you do in a single day. Without muscles, chances are you couldn't do any of them.

In order to perform these myriad of activities, three types of muscles are present in the body. These include skeletal, cardiac and smooth muscles. Skeletal muscles constitute almost half of your body weight and are attached to the skeleton. They are responsible for the overall movement of the body, as well as the ability to stay in a position for a period of time. The common physical feeling of being "weak in the knees" can sometimes be attributed to weakened leg muscles; those leg muscles help to support the knees, leg bones, and the body. Without them, the support system is highly compromised. The cardiac muscle, one of the most specialized muscles in the body is located within the heart. Finally, smooth muscle is located in the gut of the body, around the bronchi in the lungs, urinary tract, reproductive organs and blood vessels.

There are differences in the physical appearance of these muscle types, contraction strength, duration, control by the nervous system. They are all adapted to the job that they perform. However, how they operate is basically the same in every case. By knowing how they work correctly, a person can use exercise and activity to strengthen their muscles in an intelligent fashion.

Skeletal muscle, the type that most people think of when exercising is a collection of muscle cells, nerves, connective tissue and blood vessels. Each of the cells is known as muscle fibers. They are cylindrical, arranged parallel to each other and run throughout the entire length of the muscle. These fibers are held in place by connective tissue, which also attaches these bundles of muscle fibers to the bones, and conveys the force generated by the muscles to the bone across one or more joints. These connective tissues also connect muscles serving the same basic function together, and act as a pathway for blood, and nervous system commands. On a microscopic level, each muscle fiber consists of many smaller units called myofibrils. These myofibrils cause the muscle fiber to appear striated under magnification. One way to think of the muscle fiber is as a container of toothpicks, with the myofibrils represented by the toothpicks themselves.

When directed by the central nervous system, the myofibrils and the muscle fibers will contract. By specific muscle fibers contracting in a specified manner, the muscles attached to the bone and joint by the tendons cause the bone to move using a lever system.

The muscle and skeletal system, just like other simple machines work on as a system of levers. The force, speed, even the distance of the muscle moved is changed by the location of the muscle connection to the bone, or the lever. A lever is a rigid structure that moves on a fixed point, often called the fulcrum, and the movement is undertaken by the exertion of force or effort onto a portion of the lever. A good example of a lever system is a see-saw. The see-saw moves on a central, fixed point in the center of the toy. This is the fulcrum of the system. In order to move one end of the see-saw, or the resistance, a person has to sit on the other end and apply a force. In the body, the bone is the lever, and the joint is the fulcrum point. The force that is applied to the bone is provided by the muscle. There are three classes of levers, and like the simple machines seen in the everyday world, the lever systems of the muscle skeletal system can be subdivided in much the same way.

The first class lever system has the fulcrum in the center, and the force or effort is applied to either side of the fulcrum point. There are not many examples of this system in the body. One example though is that of the neck. In this case, the head balances on the cervical vertebrae and the muscles of the back of the neck allow the head to extend forward or backward depending on the desired direction. The second class lever has the resistance in the middle, while the fulcrum point is to one side. An everyday example of this lever system is the wheelbarrow. In this case, the wheel of the wheelbarrow is the fulcrum point and the force is applied by lifting the handles. One advantage of this type of lever is that a smaller amount of energy is able to lift a larger force. Muscles attached to bones in this manner are able to lift greater weights, but do so at the expense of distance and speed. An example of such an attachment is the calf muscle in the lower leg. When standing on your toes, the calf muscle lifts the body and the bodyweight passes through the ankle and around the fulcrum point of the toes. While the distance moved is not very much, and the relative speed of the movement is low, the amount of weight moved is relatively large.

The final class of levers is known as the third class. It is perhaps one of the most common types of levers found within the body. In this lever system, the effort is applied to the center, and the fulcrum point is at one end. The most noticeable example of this system in your body is the arm and the bicep muscle. In order to move your forearm, force is applied to the middle of the bicep muscle. This muscle is attached to the bone in the forearm (the lever), and the forearm is moved up, around the fulcrum point of the elbow. While the force is compromised, the speed and distance moved are increased.

So how does knowing the structure of the muscle someone with their exercising? By knowing the structure of the muscle, a person can try to understand how they operate. By realizing how muscles work, the exercise program developed can be designed to maximize the effectiveness of the work out.

For example, in order to strengthen the bicep muscle, the resistance offered (weight) should be steadily increased over time. By doing this, the force needed to be applied by the muscle is increased over time, causing the muscle to become stronger over time. In the case of the calf muscles, a possible way to strengthen the muscle is to lengthen the duration of the repetitions. By allowing the muscle to work over a steadily longer period of time, the muscle can be strengthened.

It should be realized, though, that even with the ability to target the muscles in a way that builds on their strengths, time for adjustment, and muscle repair is needed. The muscle fibers and connective tissues can be damaged if pushed to far, so be sure to listen to your body. Be sure to give the muscles time to rest in between activities. Also, be sure to get advice from a trained professional, either an exercise trainer or a medical one.

By understanding how the muscles work and how they interact with the body's skeletal system a person can try and design an exercise program that can highlight the strengths and improve on the weaknesses of the muscles in question.