The word “cardio” is short for “cardiovascular,” a term used for the circulatory system consisting of the heart and blood vessels in your body.
What people refer to when saying they “do cardio” are endurance exercises that strengthen this network. Those are done for longer stretches of time, make the heart beat faster and pump more blood through your system, which carries nutrients and oxygen to every cell.
Any activity that gets your heart rate to about 50 – 75% of your maximum heart rate can be classified as cardio. You can roughly calculate your maximum with the formula 220 minus your age. If you are forty years old, for example, it’s 220 – 40 = 180.
Does it only work with specific fitness activities? No. As long as you get into the above range, it doesn’t matter what you do. Go for running, biking, dancing, tennis, skateboarding or whatever else you prefer.
But why would we deliberately choose to do this, make our hearts beat faster and get all sweaty and exhausted? There are ten good reasons: