Using the stairs instead of the elevator is a great way to burn some extra calories while on the go, but you can also use your stairs at home for working out. It's a perfect way to get your heart rate up in the Winter without having to brave the cold, not to mention it's completely free. While trudging up and down stairs is itself a major workout for your legs, you can work your upper body too by holding a weighted medicine ball ($17). If you don't have a ball, use a set of dumbbells or a kettlebell.
Just hold the weight in front of your chest, or straighten your arms over your head for a real challenge, and go up and down the flight of stairs 10 times. When going up the stairs, skip every other step to make it even more difficult for your quads and booty. Move at a slower pace as you go down the stairs to prevent putting too much pressure on your knees. Not only does this workout require no electricity, but it's also a great way to warm up without having to turn up the heat in your home. Two green reasons rolled up in one great exercise.