INSANITY 3rd week and still GAINING

I would say building muscle because per volume, it weighs more than fat. However, I have done insanity too, and I don't really know about the building muscle part. I know I got leaner and had more endurance, but I don't know if I gained that much muscle. I would change up your eating for a week or 2 and see if that helps.

Sorry I couldn't help more...good luck!

I'm not sure what INSANITY is but with any weight loss program, what you're experiencing is ok. Like people told you before, you very well may just be gaining muscle You might want to start tracking your progress mainly- or even solely on mesurements.
As long as you're doing the right things (read: cardioascular exercise, resistance training, eating nutritious foods), your body will IMPROVE.

I just finished the Insanity workout but I didn't gain weight. I was noticing that the scale didn't show any weight loss but I could see the progress by the inches that I lost. When I started drinking alot more water was when the weight started to come off. Please don't get discouraged. This workout does work. The scale is not our friend! You will notice very soon RESUTS. As women we retain water during certain times of the month so our weight fluctuates. I went from a size 12 to a size 6 doing Insanity. My weight wasn't that much at 7.9 lbs, but my total body inches was 12! Also try eating 5 small meals a day to keep your energy up. If you need any help, please friend me. I would love to help! Diane