Understanding how cardio and calories burned works?!?!

faithchange

OK. I wasn't sure how to name this post, but I need help understanding and all.

I just finished my first 90 days of P 90X yesterday. Great results: 10 lbs lost and 11 inches. I gained much strength and probably great cardio health too.

Today, I did a workout I used to do months ago and then I was lucky to burn 400 calories in the 60 mins. Its Bob Harpers Extreme Cardio (or something like that) or maybe Ultimate Cardio...

It focuses on weights and cardio at the same time, ie; squats with weights, shoulder presses while doing heel kicks, lunge jumps with weights in hand, ect.

Anyway, in the 60 min time, I burned 512 calories which to me is impressive. Is this because my cardio fitness being stronger allowing me to burn more efficient and also able to push harder to feel the burn.? There were a few times in which I wanted to give up, but I pushed forward and felt great at the end in a big flop sweat!

I loved P90X, but right now can't repeat it....so, I'm trying to figure a program to help me with obtaining what I've gained thus far and I want to use what I've already got.

Thanks
Michelle