While I like the implied physical benefits of exercise, I've been eating mindfully and working out for a month+ doing circuit training. I haven't lost a single lb. At least not with working out. I've been working on a calorie deficit of ~600 most days. I work out 5 days a week with planned rest days. I use exercise as a means of stress management and maintaining movement. I can't think of it as weight loss because I'm not losing weight - I'm changing the shape of my body. That's it. Same poundage, but I've gained 4+lbs in muscle, increased my bone density, and likely lost the same in fat. However, the number on the scale doesn't move. To anyone who didn't understand what was happening, including the pissed off girly teenage voice in my head, this lack of change on the scale after a month+ of really hard work would be very discouraging. If I were working solely on a calorie deficit, I would likely see the change in the magic digital number.