Benefits of Regular Exercise to Cardiovascular System - Essay Example

Benefits of Regular Exercise to the cardiovascular System BENEFITS OF REGULAR EXERCISE TO THE CARDIOVASCULAR SYSTEM The main physiological features of the cardiovascular system The cardiovascular system is made up of the capillaries, veins, arteries and heart. This system is responsible for the transmission of nutrients and oxygen to the body, as well as removal of waste and CO2. The cardiovascular system is complex and requires high pressure of blood flow in order to deliver blood to the entire body (Aaronson et al, 2004: p45). The blood pressure is the force that maintains blood flowing through the system. Exercise is important for the maintenance of this pressure by conditioning the working of the cardiovascular system to deliver enough blood to muscles. This paper is a discussion of the main physiological features of the cardiovascular system. The heart, one of the system’s major components, has two ventricles at the bottom chambers of the heart and two atria at the top chambers (Aaronson et al, 2004: p47). The ventricles force the blood into the blood vessels from the heart while the atria drains and forces blood into the ventricles. The heart is divided into two chambers in order to achieve a two-circuit system of circulation. The right side pumps to the lungs while, on the other hand, the left pumps to the other organs of the body. During the cycle of a heartbeat, the right and left atria contract, then the right and left ventricles follow suit, followed by relaxation of the ventricles and atria. During the resting phase for the ventricles and atria, blood flows from the relaxed atria to the relaxed ventricles, constituting the diastole. The atria then contract to force out any remaining blood almost followed immediately by the ventricle, constituting the systole. To ensure that blood flows in the right direction, the heart has valves that allow blood to move in only one direction. The heart valves open and close when the heart relaxes and then contracts, which is caused by the pressure difference in the heart, and these valves are; aortic, mitral, pulmonary, and tricuspid valves (Aaronson et al, 2004: p50). The one way nature of the valves ensures that blood does not flow back, which avoids mixing of different blood. The heart is comprised of the cardiac muscle, which is a striated and involuntary muscle found on its walls and histological foundations (Aaronson et al, 2004: p52). While smooth muscle is also involuntary, cardiac muscle is more anatomically related to skeletal muscle since smooth muscle is not striated. The cardiovascular system is made of an amalgamation of smooth and cardiac cells, with the blood vessels lined by smooth muscle. The circulatory system is composed of two types of circulations; the systemic and pulmonary circulation. Systemic circulation receives blood from the heart via the aorta and returns blood, via the veins, back to the heart. In the pulmonary circulation, the blood leaves the heart for the lungs to fetch oxygen and release CO2 then comes back. This circulation is regulated by the cardiac cycle that has two phases. In the first, systolic contraction sends blood to the pulmonary and systemic circulation while, in the second, the diastolic relaxation causes the ventricles to relax and receive blood back into the heart (Aaronson et al, 2004: p550). The SA and NV nodes maintain this rhythm. This blood in the circulatory system has three major purposes: regulation, protection and transport. Blood transports oxygen and CO2 between the body and the lungs via RBCs. RBCs have cytoplasm with 33% hemoglobin that transports oxygen and some carbon dioxide (Aaronson et al, 2004: p550). As the blood begins to circulate, it exits the heart via the left ventricle and enters the aorta full of oxygen. On the way back to the heart, the blood collects CO2 via the veins, which is removed at the lungs and replaced with oxygen. During exercise, the muscles require as much oxygen as possible. The amount of available oxygen is determined by the blood volume that is pumped by the heart around the body, in addition to the amount of, oxygen extracted by the cells from the blood (Birch, 2004: p22). Therefore, fitter individuals increase their blood volume, increase the efficiency of the heart as a pump and have their working muscles forming more capillaries coupled to artery enlargement. The first thing that happens during exercise is an increased amount of blood flow allowing for the increased delivery of nutrients and oxygen to the muscles. This involves an increase in blood plasma levels since this reduces blood viscosity, which allows for easier movement via the small capillaries. As blood volume increases, more enters the heart during diastole causing ventricle walls to stretch and this result in a stronger systole (Goes, 2012: p1). As one becomes fitter, the heart rate decreases allowing even more blood to enter during diastole, which thickens and strengthens the cardiac muscle. During exercise, vessels in working muscle dilate, which reduces resistance to blood flow, in turn easing the pumping of blood to the muscle. Resting heart rate decreases with exercise while also remaining relatively low at given exercise intensity. Additionally, the body also recruits all its capillaries and forms new capillaries. This acts to increase the interface between muscle fibers and the blood, allowing the cells to extract more oxygen. Finally, exercise improves the dilation quality of the arteries. Inability to dilate is an early symptom of atherosclerosis and cardiovascular disease. Regular exercise has various benefits relating to cardiovascular risk factors. Physiological benefits include improvement of the body’s ability to utilize oxygen. As the ability to transport and utilize oxygen improves, one can perform regular everyday activities with less fatigue. Exercise and training also increases the capability of blood vessels to dilate, improving the ability to deliver oxygen to muscles and enhanced vascular wall function. People with cardiovascular disease who undergo some exercise regime have reported an earlier work return, as well as improvements in quality of life like self confidence, less anxiety, and lower stress (Kenney et al, 2012: p36). Sedentary lifestyles carry with them numerous health risks. One of them is heart disease, which, in the Western world is a leading cause of disability and death. Individuals who do not exercise have a twice as likely chance of having high cholesterol and blood pressure, two major risks factors for heart attack, abnormal heart rhythm, sudden cardiac death and congestive heart failure. Sedentary lifestyle also leads to stroke, which, like heart disease, involves prevention of oxygen and blood from reaching the individual’s brain, causing death or paralysis (Myers, 2010: p1). Major risk factors contributing to stroke include high cholesterol and high blood pressure. In the Western world, stroke is the third cause of death. Inability to control blood sugar is also another result of sedentary lifestyles, causing blindness, early death and heart disease. Finally, sedentary lifestyle is a leading cause of high blood pressure. If it goes undetected, high blood pressure could cause kidney and heart failures, strokes, and heart attacks. References Aaronson, Philip. Jeremy, Ward. & Charles, Wiener. The cardiovascular system at a glance. Oxford : Blackwell, 2004. Birch, Karen. Instant Notes in Sport and Exercise Physiology. New York: Garland Science, 2004. Goes, Eva. How do your Heart and Blood Vessels Adapt to Aerobic Exercise? 16 February, 2012. (November 6, 2012) Accesed from, www.suite101.com/article/how-do-your-heart-and-blood-vessels-adapt-to-aerobic-exercise-a403279 Kenney, Larry. Jack, Wilmore. & David, Costill. Physiology of sport and exercise. Champaign : Human Kinetics, 2012. Myers, Jonathan. Exercise and Cardiovascular Health. October 3, 2010. (November 6, 2012). Accessed from, www.circ.ahajournals.org/content/107/1/e2.full Read More