I've had lots of personal trainers and they all say that in order for a woman to really lose weight, and do it in a somewhat short period of time, they have to incorporate cardio. This includes walking for sure, but I've been told that women should include sprints in their cardio to get their heartrate up. I try to jog or walk for a minute or two or whatever, then run for even only 20 seconds, whatever you can handle. The sprint times will increase as you get stronger. If you're eating healthy, that is awesome. Don't get frustrated though, it took me about 4 or so weeks of working out and dieting before the weight really started falling off. I lost a couple of pounds the first month, but after that, I lost 13 pounds in about 4 or 5 weeks. It melts off of you once you retrain your body by exercising, etc.