- {Notice: I assume that when you asked for why "it" was important to overall health, 'it' was intended to refer to cardio exercise itself, and not the example.}
Cardio exercise is exercise that affects your heart. This includes your heart rate, BPM, and your heart's ability to pump blood throughout your body. An example of cardio activity is jump-roping. Cardio exercise is important to overall health because it improves my heart. My heart is a vital organ to health; this means that when my heart is improved, my blood circulation's efficiency is improved, and my overall health is also improved. Not only does cardio exercise increase your ability to perform exercise of all sorts, but it will also assist your health in the long run.