Sarcopenia Physical Changes

Over the course of aging, the main physical change involves sarcopenia; it is the decrease in muscle size and fiber number, which affects an individual’s aerobic capacity and strength as a result of the change in muscle composition. With decreased aerobic capacity and strength in muscles, this causes detrimental effects on performing any activities or tasks that consist of running, walking, moving or carrying objects, and activities required for daily living. Muscles consist of two different types of muscle fibers: type I and type II. Type I muscle fibers are otherwise known as slow twitch oxidative, and are involved in activities that require low force, low power, low speed, and high endurance; however, Type II muscle fibers are known as fast …show more content…
In a study by Arbab-Zadeh et al. (2004), they had twelve sedentary healthy seniors and twelve Master athletes that previously had pulmonary artery catheterization; they measured the participants pulomary capillary wedge pressures and left ventricular end-diastolic volumes through echocardiography at baseline, during decreased cardiac filling, and after a saline infusion. Based on these measurements, they found that Masters athletes had greater stroke volumes than the sedentary individuals at any given pressure, and that the sedentary healthy seniors had decreased left ventricular compliance. This essentially means that in sedentary individuals, when the left ventricle fills with blood, the pressure is higher at a particular blood volume compared to normal individuals. These characteristics are determining factors for health related issues such as hypertension and heart related diseases. As a result, this will affect the individual’s activity level, and unfortunately, they cannot participate in high intensity activities – whether resistance or aerobic activities – because it requires the heart to work harder, and when the left ventricle fills with blood, the pressure will be higher at even lower blood volumes compared to when they are at rest. For example, if an individual’s aerobic capacity declines dramatically over the course of aging, this means that their respiratory rate declines, causing blood pressure and heart rate to decrease, and poor flow of nutrients in the blood to the bones and muscles; this results in decreased bone density and decreased muscle mass, and therefore decreases strength and the ability for the individual to carry heavy loads or to participate in activities that require intense effort. However, if physical activity – especially resistance training – is incorporated into an older adult’s daily living, it