All About Exercise
Every one of us must have done some sort of exercise at least once in our life. Have you ever gone beyond this story? What I meant is that, have you ever put an effort to study the enormous offstage preparations taking place underneath our skin to make it happen. I don’t think many of you will give a ‘yes’ nod to the above question. Let us use a little time to go beyond the skin and I am sure that you will give a cheerful pat to your own muscles on knowing these secrets (at least to you). Physical exercises are made possible by means of forces effectuated by the voluntary muscles of the body acting through the lever systems of the skeleton.
If you happened to be in a gym or bodywork station, you might end up with reading certain terms, which explain the maximum possible force or extension of that particular equipment. Many manufacturers of exercise equipment in the United States who continue to use the antiquated English System of measurement. Among two hundred nations of the world, the United States is the only country that continues to employ the English System (as a matter of fact, even England abandoned this system a number of years ago). Other than United States, an International System (SI) is universally accepted for measurement in the world of science and in everyday life. The basic units in use to measure the force, work, and power of exercise are Newton (N), joules (J), and watts (W), respectively.
What Happens When The Muscles Are Put To Action?
During the performance of an exercise, the recruitment of motor units for the purpose of developing force between the bony attachments of muscles may or may not yield in the shortening of the muscle and drawing together of the attachments. According to the relationship between the force brought about by activation (neural signal input) and that of an opposing force acting on the attachments of a muscle, the sarcomere movement may be either as shortening or lengthening, or there may be no change in the total muscle length. When external forces lengthen the muscle, muscle activation does not cause shortening but, instead, resists the lengthening.
The development of the muscle forces and their development and the prevailing external forces will result in muscle actions that produce static exercise or dynamic exercise. In static exercise, there is no movement about the related joints while in dynamic exercise there is an increase or decrease in joint angles. Static exercise of activated muscle is normally termed as isometric. Although, force is developed there is no movement and hence no work is performed. All the other muscle actions involve movement and are termed dynamic. The term concentric is used to categorize a shortening action and the term eccentric is used to identify a lengthening action.
The energy of physical exercise can be equated in terms of the potential energy of the biochemical substances utilized for muscular actions (essentially ATP, CP, carbohydrate, and fat), the actual release of this energy as muscle cells develop force, the heat generated, and the kinetic energy of the human body or objects used in an exercise routine or in a competitive sport.
In other words,
Metabolic Energy Release (J) = Work (J) + Heat (J)
The total energy manifested in actual performance results in work performed on the body itself, work performed on an object (such as a ball, while you are playing some game), or work performed on an opposing player (as in contact sports). Whatever energy, does not yield work turns up in the muscles and, subsequently, in other parts of the body as heat. The ratio of work performed to the energy utilized is termed as mechanical efficiency.
For example, a person who utilizes 1,500 J of energy to perform 500 J of work on a cycle ergo meter develops 1,000 J of heat in the body that must be dissipated to retain normal body temperature. Dividing 500 J of work by the 1,500 J of energy utilized (and multiplied by 100 to express as a percentage) results in the determination that the person’s mechanical efficiency for the exercise was 33.33 %.
My next post will show how to measure exercise performance.
