Diseases of the Cardiovascular System - Essay Example

? EXERCISE SCIENCE EXERCISE SCIENCE The current era of ever advancing innovations and technologies has made our lives easier and has brought everything within a person’s reach. With all the sedentary comforts, life moves smoothly, until one day the person chokes of sudden chest pain that creep him out of his wits. If the person is lucky enough, he gets warning signals long before in the form of pot belly or love handles. Sadly, not many are alarmed by this as the accumulation of fat is slow over the long period of time to herald an alarm signal. The vicious cycle of inactivity, obesity and cardiovascular disease risk has taken a toll in today’s society and the situation continues to get worse. The reason for this increase lies in the multifactorial etiology of the bases of these events. Inactivity serves as the breeding ground for a multitude of health problems. Genetic, personal as well as environmental factors are implicated in the pathogenesis of diseases budding from the lack of physical exercise. An understanding of all these factors is important in order to address the underlying problem and understand the role of exercise in the maintenance of health and wellbeing. We consider a typical case scenario from everyday life to understand how inactivity leads to the buildup of fats which later on serves as a death invitation in the form of cardiovascular diseases. Mrs. Patel, a 56 year old, obese lady of Indian origin seeks medical advice after experiencing chest pain on exertion. Her personal history reveals some significant points which include her lack of physical activity and the fact that she uses ghee (form of oil with high saturated fat content) to prepare her food. These factors lead to Mrs. Patel being diagnosed as a case of coronary heart disease. Lack of exercise is accompanied by a constellation of medical conditions. The most harmful among these in the long run include atherosclerosis, hypertension, stroke, type 2 diabetes mellitus, angina, myocardial infarction, depression and osteoporosis (Bouchard 2000). Obesity is an inevitable consequence of inactivity and is an additional comorbid factor for a number of other diseases and a bad prognostic factor. Physical inactivity upsets a number of metabolic activities in the body and its effects are evident in almost all systems of the body. One such condition, the metabolic syndrome is heralded by the presence of central obesity, cardiovascular disease risk, hypertension and diabetes and hormonal disturbances (Boon and Davidson 2006). Diseases of the cardiovascular system account for greater than five million annual deaths and thus are the single leading factor responsible for mortalities among developed countries (Kumar et al 2005). The core abnormality is accumulation of fats. Body maintains its healthy state of metabolism when consumption of calories is equal to the amount of calories spent or burnt, either in the form of daily activities or as a part of exercise training. When energy intake exceeds the expenditure, the extra calories are stored in the body in the form of fats (Slentz et al 2004). As evident in Mrs. Patel’s case, lack of physical activity coupled with overeating or consumption of unhealthy foods leads to net accumulation of calories. The pathological process affects a wide spectrum of body systems. The blood vessels suffer damage as a result of deposition of fibro- fatty material in the intimal layer, eventually obstructing the vessel lumen and hindering the flow of blood. The initial lesion ‘fatty streaks’ evolves into 'foam cells' after infiltration of local inflammatory cells. The active inflammatory cascade ensues as the progression of atherosclerosis forms lipid rich atheroma and later on fibrous plaques. These plaques both remain stable and over the time obstruct the lumen, or they may rupture resulting in acute hemodynamic events (Kumar et al 2005). As the lumen becomes narrower, the 'silent killer' hypertension sets in to play. The cardiovascular risks of obesity are also evident from the fact that more than 75% cases of Hypertension are attributed to obesity (Krauss et al 1998). The workload on heart muscle increases as it has to pump blood against greater resistance offered by the narrow vessels. As a result, the heart muscle undergoes remodeling and hypertrophy. Even though basically a compensatory mechanism, it serves as a two-way sword as the ability of heart muscle to pump effectively is compromised during the process of remodeling. Also, the increased oxygen demands of the now hypertrophied heart muscle are not met effectively by the declining function of the cardiovascular system. This leads to a vicious cycle of increased load on heart- compensatory hypertrophy- increased myocardial oxygen demand- further decline in heart function (Boon and Davidson 2006). The symptoms of the declining heart function initially appear on exertion only, because that is when the oxygen demand on myocardial muscle increases. Mrs. Patel presents as a typical case of angina pectoris, whose hallmark is chest pain on exertion (Boon and Davidson 2006). As the disease progresses, the symptoms appear with less exertion or even at rest. Acute coronary syndrome is the term given to the sudden cardiac symptoms that appear at rest and without any precipitating factors. These include variant angina and myocardial infarction. These are among the fatal end effects of the spectrum of cardiovascular diseases. Fortunately, these fatal outcomes of cardiovascular diseases are preventable. With profound understanding of the basic mechanisms leading to these catastrophic mortalities and the culprits involved, it is possible to address these individual risk factors at an early stage and turn a potentially high risk cardiovascular patient into a low risk one. The most common cardiovascular risk factors that are amenable to change include inactivity, obesity and consumption of food items with high LDL and cholesterol content (ghee in case of Mrs. Patel). Physical activity forms the corner stone of maintaining a healthy life style and offers protection from the cardiovascular diseases. The relation of exercise with the diseases of cardiovascular system is clearly evident from the fact that exercise testing serves as a major diagnostic adjunct in diagnosing the heart diseases. Not only does it serve to minimize the risk of heart disease in normal people, but also serves to effectively rehabilitate the people surviving previous heart problems. Apart from having a direct impact on enhancing a person's exercise capacity and endurance, it also affects the individual disease risk factors and serves to modulate them, significantly lowering the cardiovascular morbidity and mortality. According to a study published in the book, ‘physical activity and obesity’, the amount of exercise accounting for expenditure of 4200 KJ energy each week results in decreased number of deaths related to all types of causes (risk factors) in younger as well as older individuals (Bouchard 2000). The direct effects of exercise on heart muscle include decrease in myocardial oxygen demand and enhanced functional capacity of the heart (Fletcher 1996). Exercise training in any form is beneficial for producing cardiovascular adaptations to increase endurance, exercise capacity and muscle strength. This requires the incorporation of regular exercise regimens that includes the use of large muscle group of the body, like swimming, running and jogging (Thompson et al 2003). Apart from strengthening bones and muscular system, regular exercise also balances the fat deposition in the body and keeps the person in normal body mass index (BMI) range. Central or abdominal obesity is particularly harmful and is correlated with the metabolic syndrome (Bouchard et al 2007). Physical activity is a source of primary as well as secondary prevention of cardiovascular diseases. It lowers the blood pressure, improvement in lipid profile and glucose tolerance. It also affects the blood vessels by improving endothelial function, improving fibrinolysis and reducing inflammation (Topol et al 2007). The obesity and the resultant cardiac problems in Mrs. Patel can be effectively encountered by the combination of strategies involving exercise and behavioural programs aiming at changes in eating behaviour (Shaw et al 2006). The physical exercise of over 30 minutes daily is the general recommendation (Slentz et al 2004). However in order to correct chronic imbalance comprising of obesity and underlying cardiovascular risks, a 60 minute moderate to high intensity exercise may be helpful to provide long term benefit (Jakicic 2003). Bibliography 1. BOON, N. A., & DAVIDSON, S. (2006). Davidson's principles & practice of medicine. Edinburgh, Elsevier/Churchill Livingstone. 2. BOUCHARD, C. (2000). Physical activity and obesity. Champaign, IL, Human Kinetics 3. BOUCHARD, C., BLAIR, S. N., & HASKELL, W. L. (2007).Physical activity and health. Champaign, IL, Human Kinetics 4. FLETCHER, G. F. 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