Pump it up that mean you, everything start with you. If you want to stay fat stay fat. Enjoy yourself have another brownie or what ever you shove in that pie hole, what the hell  you don't mind being thought of as a fat bastard!! and the best part you can be all that you wanted to be, You don;t need to walk far, climb stair's or even take care of yourself. Soon  you will be using a toilet brush to wipe that fat ass of yours.  But ! if you want to take personal responsible , you will get into some sort of shape. You will be able to move better, climbing stairs will not stop you from doing things that is above street level.  An best yet you may never know what it's like to wipe with a toilet brush.