I live on the fourth floor of a building with no elevator. When I know I dont have a lot if time to workout I use my building to ny advantage. I run up and down four flights of stairs. Doesnt sound too hard right??? Well try it for yourself. Run up and down stairs for 20 minutes. I gurantee you will be panting from that workouthttp://pinterest.com/pin/285274957619761342/ here's a link to some great stair workouts.