e. hypertrophy). In the elderly, this process is reverse. Hence, the functional reserve capacities of the skeletal muscles decline with age, largely due to diminished levels of physical activity. As a result daily tasks once taken for granted become progressively more difficult, and eventually impossible, to perform. In illustration, a great deal of muscle force is required to simply stand up or to climb stairs. Therefore, skeletal system is relying upon the reserve capacity of the heart to provide the endurance needed to perform such activities. If an elderly person does not engage in some sort of endurance-based activities, he or she will not have the cardiac reserve capacity needed for daily tasks. More importantly, diminished capacity may not counteract illnesses or diseases. Although strength-based activities help the cardiac reserve, it may not benefit the skeletal system. "While resistance exercise promotes fiber hypertrophy in skeletal muscles, the explosive power of muscles still declines with age. Hence, while physical activity is important in attenuating age-related changes in muscle function and its reserve capacity, it delays rather than prevents the deleterious effects of aging" (Lakatta, 1994).
As physiological changes occur in the musculo-skeletal system, there is generalized atrophy of all muscles accompanied by a replacement of some muscle tissue by fat deposits. As a result, some loss of muscle tone and strength is evident. For example, the ability to breathe deeply is reduced, coupled with diminished gastro-intestinal activity, thus leading to constipation or bladder incontinence, particularly in women. Additionally, calcium is lost, and bones become brittle. Accordingly, these results in osteoporosis and a reduction of weight bearing capacity, leading to the possibility of spontaneous fracture, vertebrae thinning, and weight reduction. Such changes contribute to vertebrae can calcification and postural changes. Critically, the joints undergo changes, resulting in arthritis, which is the most common chronic condition in the elderly.
Undoubtedly, the muscular cellular changes have a direct correlation to several disorders occurring in two systems experienced by the geriatric population: Muscular and Skeletal.
Changes in the cardiac muscular system result in atrophy of the heart muscle, especially in the left ventricle, calcification of the heart valves, and loss of elasticity in artery walls. Similarly, musculo-skeletal system experiences atrophy of all muscles accompanied by a replacement of some muscle tissue by fat deposits. Hence, the common denominator is atrophy, meaning the partial or complete wasting away of a part of the body, which is general physiological process of a breakdown of tissues. This results in some loss of muscle tone and strength, triggering susceptibility and vulnerability to illnesses and diseases. Sadly, inactivity has become an accepted part of life; more exploration is warranted to detail the benefits of habitual physical activity; hence, this information may be used as a community-based educational tool to help prevent or delay cardiovascular disease, obesity, arthritis, and the frailty associated with old age.
Cardiac muscle is so named because it is found in the heart. Cells are joined to one another by intercalated discs, which allow the synchronization of the heartbeat. Cardiac muscle is branched, striated muscle.
Skeletal muscle, which is attached to bones by tendons, is associated with the body's voluntary movements. Skeletal muscle is striated muscle. Unlike cardiac muscle, the cells are not branched. Skeletal muscles are voluntary muscles because we have control over their contraction.
Visceral (Smooth) Muscle
Visceral muscle is found in various parts of the body such as the arteries, the bladder, the digestive tract, as well as in many other organs. Additionally, Visceral muscle is also called smooth muscle because it does not have cross striations. Visceral muscle contracts slower than skeletal muscle, but the contraction can be sustained over a longer period. Visceral muscles are involuntary because they are not consciously controlled.
Bailey, R. (2011). Muscle tissue. About.com Guide. Retrieved from http://biology.about.com/od/anatomy/a/aa022808a.htm
Carpi, A. (1999). Basic anatomy - tissues & organs. Retrieved from http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
Lakatta, E.G. (1994). Cardiovascular reserve capacity in healthy older humans. Laboratory of Cardiovascular Science, Gerontology Research Center, National Institute on Aging, 6(4): 213-23.