When PHA3 was released I thought too that it had more of a cardio effect than the the other PHA workouts. Now, I don't know. Ive been incorporating PHA Training from the Strong and Sweaty Series in my February rotation and I am so winded and sweaty after the workout, I have to cool down before I can take a shower. And I've also noticed that my calorie burn is really high at the end of the day. At first I thought PHA 3 had more of a cardio factor, now I think they may be even. Any way, I love the pure metabolic resistance training offered in PHA training. It allows me to lift heavier and I also like that the only equipment needed is a step and dumbbells. So maybe its just me, but I fell in love with PHA training all over again. I also like that in your older dvds, that there are clips of the workout with music when the dvd is inserted. I miss that feature, because it motivates me while I'm setting up my equipment. Cathe I absolutely love all of your PHA workouts and I hope you make more in the future. Three isn't enough.