The cardiovascular system is composed of the heart and blood vessels, and the blood vessels are divided into five groups: arteries, arterioles, capillaries, venules and veins, according to Vanderbilt University. The effects of the cardiovascular system are wide ranging, and include participation in gas and nutrient exchange and thermoregulatory processes, along with the governing of a person's aerobic capacity. The cardiovascular system works in concert with the body's other systems to keep a person healthy and vital.
Participates in Gas and Nutrient Exchange
The cardiovascular system participates in the important processes of gas exchange, nutrient and oxygen delivery, and the removal of carbon dioxide and other deleterious metabolic byproducts from the body's cells. According to the Merck Manual, the cardiovascular system bathes the lungs in blood by a process called perfusion, and the body's circulation provides a crucial link between the oxygen-containing atmosphere and the oxygen-consuming cells. The delivery of oxygen and nutrients to the muscle's cells depends both on the lungs and the circulatory system. It's in the capillaries where oxygen is dumped from red blood cells into the tissues and carbon dioxide extracted for removal. The capillaries also are the site of nutrient and waste exchange. Cellular waste products are then sent via the blood vessels to the excretory organs or organs of elimination, such as the liver, kidneys and lungs.
Assists Thermoregulation
According to the University of Illinois at Chicago, the cardiovascular system assists thermoregulatory processes and can either warm or cool the body. Because of the body's desire to maintain homeostasis or keep internal conditions within a precise range, it transfers heat from areas of relative warmth to areas of relative coolness to help maintain a consistent body temperature. In normal, healthy humans, the body temperature is approximately 98.6 degrees F. When the body is exposed to warmer temperatures or feels hot, the capillaries (the location of water, gas, nutrient and waste exchange) lying close to the skin dilate or open up to allow increased blood flow toward the body's outer surface, which helps vent heat and cool the body. When the body is exposed to cooler temperatures, the capillaries lying close to the skin constrict or close down to shunt blood flow away from the body's surface and conserve heat. The vasoconstriction of blood vessels upon the body's exposure to cold temperatures helps keep the core, which contains the body's essential organs, warm and functioning properly.
Governs Aerobic Capacity
The cardiovascular system plays an important role in governing a person's aerobic capacity of VO2 max. VO2 max is a measure of the rate of oxygen a person can consume during maximal exercise. According to the Running Planet website, aerobic capacity and VO2 max depend, at least in part, on the cardiovascular system's ability to transport oxygenated blood to the working muscles. The three main cardiovascular system factors that affect VO2 max include stroke volume (the amount of blood ejected from the heart each beat) maximum heart rate and the density of a person's capillary network. An efficient cardiovascular system in a trained individual will possess a higher stroke volume, because the heart will be larger and stronger and capable of pumping more blood per beat. Maximal heart rate largely is set and does not respond to training the way other aspects of the cardiovascular system do. Aerobic training will help expand the capillary network, which provides more avenues for oxygenated blood to reach the tissues during exercise.
