Cardiovascular fitness is a general term that refers to the overall health of the heart and vascular system, often referred to as the circulatory system. These parts of the body are responsible for delivering oxygen to the organs. Many different organs and tissues, particularly muscles, use a great deal of oxygen during prolonged or intense physical activity. Cardiovascular fitness increases the body's ability to efficiently deliver oxygen where it is needed in order to facilitate greater physical exertion. Fitness can be increased through various endurance-related exercises, such as running or swimming, that involve maintaining an elevated heart rate for a prolonged period of time.
There are many different factors that affect an individual's overall cardiovascular fitness. An individual's heart rate determines how quickly one's heart can pump more blood through the body. Stroke volume is the amount of oxygen-rich blood that one ventricle of the heart can pump with each beat of the heart. Maximal oxygen consumption is the amount oxygen that an individual's body can effectively take in, transport, and use during a specified period of time of exercise. All of these are elements of cardiovascular fitness that can be improved through exercise and a healthy diet.
Increased endurance is only one of the many benefits of improved cardiovascular fitness. The heart, lungs, and circulatory system all benefit from increased fitness, allowing for more efficient blood and oxygen movement throughout the entire body. People with high blood pressure can use cardiovascular training to decrease their blood pressure to a healthier level. Increased cardiovascular fitness and cardiovascular activity also increase the body's resting metabolic rate, so the body can burn calories at a higher rate even when resting. Cardiovascular training even causes endorphins to be released into the brain, resulting in a general feeling of well-being and a decrease in stress, anxiety, and depression.
While most different types of exercise do improve cardiovascular fitness in some way, there are some types that are particularly beneficial. Many people feel that the only way to improve their fitness is to spend time each day on a treadmill or elliptical. There are, however, many other options that can be considerably more enjoyable. Running is a very effective cardiovascular exercise that can be fun and interesting, particularly if one runs outdoors through interesting landscapes. Sports such as tennis can also provide an excellent workout to increase cardiovascular fitness without the monotony of spending hours at the gym.