Walk Up Stairs, Firmer Butt!

With my pedometer clasp on my waistband, I've been walking quite a lot lately especially going up and down the stairs at the office. Three flights up, three flights down. On average, I walk up and and down like 3-4 times a day. At least.
Though my weight has not shown much improvement, I can feel that my butt has become firmer. And just last night, I noticed that the cellulite that used to bother me a lot, has dramatically become smoother! Now, that's a huge achievement!
So, for you out there - forget the escalator or the lift, just walk up and down the stairs. Get the butt firmer!