The Science Of Physical Exercise
In the past humans have been animals who could only survive through physical activity, but technology has changed the nature of survival. Humans are becoming more sedentary. The word “sedentary” originally referred to the process of becoming a farmer instead of a nomad. The farmer is less physically active than the nomad. Furthermore, the industrial worker is less active than the farmer and the technical adviser is less active that the industrial worker. So as civilization has progressed we have become more sedentary.
In the world of technology, physical activity is replaced by machines, which we can control with our hands, feet, and eyes. Mental activity is enhanced while mental serenity and stability are forgotten, causing stress. Also, personal emotions and spiritual advancements are neglected. In result, our lives seem to be easier, but at the expense of our health. In our search for comfort we have created a lifestyle that is comfortable yet harmful. This lifestyle is a social disease and is killing many people. Luckily it can be cured by breaking away from society and keeping the body active.
Physical exercise is necessary according to the book Ejercicio Fisico (1993) by Dr. J. Galilea Munoz. A sedentary lifestyle may contribute to many diseases and disabilities, especially as a child grows into an adult. Some conditions, the causes of which have been linked to a sedentary life style, are: obesity, hypertension, arterial sclerosis, heart disease, and arthritis. Furthermore, it affects the body’s equilibrium and development, which can result in misperceptions of sensations such as hunger, thirst, sexual desire, and sleep.
There are scientific reasons why each part of the physical body is benefited by physical exercises according to Ejercicio Fisico (1993).First of all the skeletal and muscular systems are benefited by physical activity. The bones, which permit movement and protect the organs, are always regenerating their mineral content, which is made of mostly calcium and phosphorous. This regeneration process is dependent on the weight and tension to which the bones are subjected. Therefore, moving, supporting, and otherwise exercising the body regenerates the mineral content of your bones. If you are inactive, your bones begin to deteriorate.
The joints between your bones also need exercise. Joints are made up of tendons, ligaments, and cartilage. The tendons and ligaments need activity to keep them flexible and healthy. Cartilage is the padding between bones that is lubricated with sinovial fluid. This fluid is stimulated by exercise; therefore, inactivity causes a lack of fluid and cartilage dries up like a sponge, becoming more brittle.
The skeletal muscles are directly or indirectly connected to the joints by tendons and made up of long thin fibers. There are two types of muscular action to note while exercising: isotonic contraction and isometric contraction. Also, each of these types of action are coupled with a type of metabolism: aerobic metabolism and anaerobic metabolism.
Isotonic contraction is when the strength of your muscles can overcome the force of resistance and your skeleton moves. When your muscles perform isotonic contraction they move with ease, build endurance, and use the aerobic metabolism. Aerobic metabolism takes place only when there is enough oxygen in the blood and the muscles are already warm. It only takes 20 to 40 seconds of warming up to activate the aerobic metabolism. In this process the muscles produce carbonic acid which passes through the blood and is exhaled as carbon dioxide. Therefore, breathing deep and rhythmically is very important while exercising. Regular practice of this type of exercise can establish endurance, flexibility, holistic health, and red muscle tissue. When done properly almost any exercise can be an aerobic exercise as long as you warm up properly.
Aerobic exercise enhances the circulatory and respiratory efficiency. It is a vigorous type of exercise that allows you to have more endurance especially in your heart and lungs. Though you can reach aerobic metabolism fairly quickly, to actually have an aerobic workout you must exercise vigorously for at least 12 minutes. Some aerobic exercises include running, swimming, and riding a bicycle.
Isometric contraction is when the muscle strength cannot overcome the resistance and the skeleton does not move. This type of action is necessary for instantaneous strength rather than endurance. If the muscles act in isometric contraction or exert energy without warming up, then anaerobic metabolism begins. This allows you to hold weight beyond your limit for a short amount of time or perform an intense activity for a few minutes. However, during anaerobic metabolism lactic acid is secreted from the muscles. Lactic acid can only be eliminated by resting for some time and if it is not eliminated then cramps occur. Isometric contraction is used for specific actions and exercises such as weightlifting, sprinting, and self-defense. It develops white muscle tissue, which is used for strength instead of endurance.
Regular and progressive training can increase the endurance of red muscle tissue and the strength of white muscle tissue. Aerobic exercises that use isotonic contraction build elasticity or flexibility, tone or muscle tension, and resistance or endurance. To develop this flexible kind of musculature, warming up is necessary before performing regular prolonged exercise. You should not get out of breath and should be able to endure moderately intense exercise for some time. Anaerobic exercise builds muscular strength, muscular potency or explosive force, and muscular hypertrophy size increases. To develop this you must over-exert the muscles to their maximum limit over and over again. Resting for one minute, between 20 or 30 second periods of anaerobic exercise, is necessary to release lactic acid.
Also, the entire body works together to move. All muscles are connected and participate in movement together. When one muscle moves, all the other muscles in the body are active in one way or another. Muscles are used for strength, breathing, and support as well as for motion. The joints work similarly. Even if a joint is not in motion it is working with the joints that are in motion by giving support. Therefore, if you stand and exercise your arms, then your legs, back, and abdomen are also being exercised. This does not mean that holistic exercise can be achieved by only exercising one part of your body. However, it is important to value all exercise or all parts of your body equally.
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