I have to say running  really shapes the legs and butt better than any other exercise I have ever tried. I play a lot of hockey and did a lot of step aerobics (over 10 years) and no results. But by jogging over the last 6 months, my legs smaller and for the first time since I have been about 14 years old my cellulite has reduced significantly.

I'm sure that with weight training I would have achieved better results. However,  I find being in a gym painfully boring and consequently too high a price to pay for better legs.