I’ve always liked walking a lot. Like so many others, I find it to be a meditative practice that helps me work through my thoughts. (Not to mention, it’s a great time to listen to music and podcasts.)

Before this experiment, I’d already been walking 10,000 on most days. Hitting this threshold was pretty easy to do: I’d usually reach it just by walking to a distant cafe for coffee, walking to digest my dinner, and going on occasional hikes.

But I started to wonder what would happen if I walked significantly more. How long would it take? How would it feel? If regular walking is associated with reduced heart disease risk, lower blood pressure, and a decreased mortality rate—what could super-walking do? 

To find out, I reached out to mobility expert Kelly Starrett, DPT for some guidance. Starrett is a coach, physical therapist, and author who champions walking as a restorative daily practice.

“[I] want walking to be viewed as a necessary biological process, like sleeping, drinking water, or eating food,” Starrett says. “That’s how important walking is to the system.”

Starrett notes that walking 8,000 steps a day is an attainable goal for most people—but there’s no reason to stop there if you want to do more. The more the merrier as long as you gradually increase your steps over time to ensure your body can handle the extra activity, he says.

“There’s some real magic that happens when you walk past 90 minutes,” Starrett explains. With this in mind, I settled on my challenge of walking 20,000 steps a day for two weeks.