Back when I was struggling to lose weight, I used to spend hours in the gym doing traditional cardio. Classes, treadmill, swimming, the elliptical, I tried them all. I couldn't understand why I was so hungry all the time. The worst part was the fact that I looked old and tired. Why? I was burning muscle.
I stopped doing conventional steady state cardio, and I started doing intervals instead. I admit that the most powerful aspect of training that I use with my clients is weight lifting, but you may want to train on the days when you don't lift. That's what the "Name Game" is for. I found one of these lists on Facebook. I took out the crunches, added some of my favorite interval moves, and here they are. Just use the letters of your name to spell out a training session. The optimal duration is just 11 minutes, and you will be triggering fat loss, not burning muscle.