Cardiovascular fitness, sometimes referred to as aerobic fitness, is the ability of the lungs to provide oxygen to the blood and of the heart to pump oxygen-enriched blood to body tissues. A more everyday definition is the ability to sustain a continuous activity level for an extended time. Running, walking and swimming are examples of exercises that build cardiovascular fitness. In fact, any activity that raises your heart rate and keeps it up it up for some time functions as cardiovascular exercise, also called simply cardio. This fitness is the result of your your heart, lungs, muscles and blood working together in concert while you exercise.
According to the National Strength and Conditioning Association, this kind of fitness is linked to a reduction in blood pressure, reduced risk of developing coronary heart disease, lowered incidence of diabetes, decreased risk of stroke and heart attack, lower fat mass, increased bone mass, improved energy levels and greater resistance to illness and fatigue. These benefits are attributed to cardiovascular exercise as much as they are fitness. Benefits decline if exercise is not regular and consistent.
If you follow a regular program of cardio exercise, your risk of high blood pressure and stroke are also lowered. The level of HDL, or “good” cholesterol tends to rise. The level of triglycerides, linked to coronary heart disease, falls. Persons who have heart attacks have better survival rates if they start and maintain a program of cardiovascular fitness training.
The American Heart association points out that cardiovascular fitness is strongly recommended to help you lose weight and keep it off. Cardio is useful for countering severe weight gain or obesity as well as related conditions like Type two diabetes. Effective weight loss does require more than the minimum level of cardiovascular exercise. The Walking Site suggests you build up to 45 to 60 minutes a day at least five days per week.
This has been shown to have other benefits, like a reduced risk of colon cancer, according to the American Heart Association. If you smoke, you’ll find it easier to cut down on the tobacco even if you don’t manage to quit entirely. It is also associated with reduced feelings of depression, more energy and an improved sense of well-being.
This type of fitness is expressed as your VO2 max — the maximum volume of oxygen you can take in through your lungs, pump around your body using your heart and blood vessels and then make use of in your muscles. Fitness can be assessed using a number of tests, including treadmill tests, step-up tests, cycling and rowing tests. Rudimentary fitness tests are often hard-wired into common cardio exercise machines so you can assess your CV fitness without having to go to a sports science laboratory.
As you get fitter — for example after an extended period of performing regular aerobic exercise — your body makes numerous adaptations that result in improved cardiovascular fitness. The muscles involved in respiration — your intercostals and diaphragm — get stronger and more efficient. The capillaries in your alveoli — the tiny blood vessels that supply the air sacs deep in your lungs — increase in number. In short, you become better able to take in oxygen and exhale carbon dioxide. Your heart gets stronger and more efficient as you get fitter. A fit, strong heart can pump more blood per beat than a smaller, less fit heart. Your muscles also get fitter and stronger as a result of exercise. The number and size of the capillaries that deliver oxygen to and take carbon dioxide from your muscles increases. The number and size of mitochondria — the energy-producing cells — also increases.
Cardiovascular exercise is beneficial and healthful but does not come without risks. If you have been sedentary for a long time, are significantly overweight, are suffering from any form of cardiovascular or metabolic disease or have any joint problems, seek medical advice before beginning any sort of new workout routine.