As taken from “Ask Dr. Bob” of the May 2017 issue of Men’s Journal:
Stairclimbing. It’s been my go-to routine for years, and I’m happy to report that a recent study from McMaster University (where much of the cutting-edge science on interval training is conducted) found that just a few minutes can significantly improve cardiovascular fitness and heart health. Researchers there had exercisers do three 20-second stair sprints up and down one flight of stairs, with recovery time in between. Including a light warm-up and cooldown, the whole routine took only 10 minutes. It doesn’t get more low maintenance than that! Better still, you can do this workout anywhere. When I was covering the wars in Sudan in the early aughts, I would run up and down the eight flights of my rickety old hotel in Darfur to sneak in some exercise.