When most people hear the word "Cardio", their mind automatically pictures jogging, or threadmills, or stationnary bikes. Yes, those are some forms of cardio. They also think it's only purpose is to loose fat. But doing cardio has many benefits.
So you see, cardio has alot of benefits that far surpass any aesthetic reason. But where does Cardio fit in ones body building routine? Well that depends on your body type. If your like me, and have a hard time gaining muscle. Then you should be carefull when doing cardio. I was worried that cardio would give me less gains, but then after seeing all the benefits that cardio can give you, I decided that it was worth doing them for the sake of my health. So I only do them 2 times a week. But for someone who wants to loose weight, doing cardio 3-5 times a week would speed things up.
So what type of exercise constitutes cardio? Well you have your basic exercises like jogging, rollerbladding, swimming. But cardio could be any type of activity that requires alot of moving. Sports like basketball, football, soccer could be considered cardio. Or you could een get creative, you could take a heavy bag of sand, put it up on a table or anything else, and just pick it up and put it back down several times. It could be hitting a punching bag. Use your imagination.
The most important thing is that you keep cardio fun. Since it's pretty easy to get bored sitting on a bike in the gym. So taking a ride on a bike in the woods would be alot more fun. Think about that when you think up some type of cardio you'd like to do. "Will I like doing this?"
That's pretty much it as far as cardio is concerned, It's a great way to keep healthy. So you'd be an idiot NOT to do some cardio.