Each cardio segment comprises 5 minutes of stair climbing. Begin by running up one flight of stairs and walking back down. Then run up two flights of stairs and walk down. Continue adding one flight at a time and walking back to the bottom between each set. When you're able to run up all the flights in your stairwell, continue this run/walk pattern for 5 minutes.

To decrease intensity, walk up the stairs, or walk up every other flight. To increase intensity, run up two steps at a time.