For every plate of food you devour, you can do five sets of stair lunges to make up for it. If you suck in your stomach while you're doing this exercise, you'll be toning your abdominals while working out your quadriceps. This takes 5 minutes tops if you do it right.
After you've digested, pick a flight of stairs and skip two to three steps to create a lunge position and continue until you've reached the top of the staircase. Then repeat down the stairs, backwards.
[Photo via @haloheadband]