I am a yoga fan. I call my self a fan because I do not do it but know little bit about it. There are many forms of yoga. If you are interested in cardiovascular exercise you should do heavy breathing exercises, kapalbhanti and few postures. Yoga targets every muscle in the body including internals of stomach. I read some where "what a yogi does in a cave is what an athlete does outside". I know this statement sounds little farfetched but you need to study yoga more. I did take yoga lessons and let me tell you it DOES have cardiovascular effect. I read the article which denies the cardiovascular effect of yoga but that is only looking at one side of yoga not all of it. -Shiv