The cardiovascular system includes the heart, arteries, veins and capillaries. The structure and function of this system decreases with inactivity and disease, but can be improved when a person participates in a regular program of aerobic and resistance exercise. Diseases resulting from unhealthy changes to the cardiovascular system include coronary artery disease and peripheral artery disease.
Types
Structural and functional changes occur within the cardiovascular system as a person ages. If a person is sedentary, his heart muscle walls become thicker. More plaque builds up on his blood vessel walls, making them thick as well. Thick walls within a person's cardiovascular system decrease the system's ability to circulate a sufficient amount of blood throughout his body.
Features
Healthy arteries expand and contract easily to propel blood throughout the body. The heart does not have to contract as forcefully to pump blood through healthy arteries compared to plaque-hardened arteries. Plaque buildup on the walls of the arteries reduces the elasticity of these vessels and forces the heart to work harder. The heart muscle will thicken over time because it is working against greater resistance, just as a bicep muscle grows when lifting heavier and heavier weights. This reduces the volume of blood that can flow into a person's heart and therefore reduces the amount of blood that can be pumped out to the body. A thick heart must pump more often compared to a thin heart to circulate the same amount of blood. A person with a healthy cardiovascular system has a lower heart rate compared to a person with an unhealthy cardiovascular system.
Significance
A heart pumping blood into hardened arteries in the body exerts more pressure against the arteries, increasing a person's blood pressure beyond healthy levels, leading to high blood pressure. Plaque buildup within the arteries feeding the heart muscle cells reduces blood flow and the amount of oxygen going to the heart. If there is little blood flow to a small area of a person's heart it causes chest pain or angina. If blood flow is interrupted to a large portion of his heart, it can cause a heart attack. Hardened arteries in the periphery or extremities cause painful cramping in the muscles, loss of hair and sores on the legs that will not heal. This condition is called peripheral artery disease.
Considerations
A sedentary person does not have to do hours of hard running or a difficult aerobics class. She will benefit from improvements in her cardiovascular system even with light to moderately intense walking. She can do three 10-minute sessions, two 15-minute sessions or a single 30-minute bout of aerobics per day to realize the health benefits, according to the American College of Sports Medicine. Aerobic exercise maintains a healthy thickness of a person's heart and reduces her risk of high blood pressure, coronary artery disease and peripheral artery disease.
Warnings
A sedentary or obese individual already has some disease in his cardiovascular system. He must consult with his doctor prior to beginning an exercise regimen. Exercise increases the stress placed on his heart and blood vessels, which may lead to a dangerous rise in blood pressure and a heart attack.
References
- "Anatomy & Physiology"; Gary Thibodeau, Ph.D., and Kevin Patton, Ph.D.; 2007
- Mayo Clinic: Aging: What to expect as you get older
- MedlinePlus: Peripheral Artery Disease-Legs
- American College of Sports Medicine: Physical Activity and Public Health Guidelines
