A common question people ask:
"I need to lose weight. Should I just do cardio until I lose the fat and then start strength training?" NO! Adding muscle will help you lose the fat, help you keep it off for the long term, really change your shape, and a number of other benefits. Here is a pretty good image. If you just diet and run, you will lose fat but also muscle. If you work on adding muscle as well, your body composition starts to look like image 2. That's what gives you the smooth thighs (no dimples) and pronounced abs!