But it’s also possible that the method can help you better your time too. Galloway himself clocked his best time of two hours and 16 minutes in the event at the 1980 Houston Marathon when he took a 15-to-20-second walk break every two miles. As for me, this method helped me shave 11 minutes off my previous marathon time.

What are the downsides of the walk-run method?

Though there are tons of amazing benefits of the run-walk method, it also comes with some drawbacks. For one, folks—like me—who are used to nonstop running may struggle at first to find their rhythm, though Galloway believes that eases the more you do it. I found the switch between running and walking a little distracting during some training runs, though it didn’t bother me during the race.

What’s more, the plan can be psychologically tough to stick to early in the race, when you’re feeling fresh and raring to go, and everyone around you is still running. That’s something I dealt with in London, when literally everyone was passing me during my first handful of walk breaks and I had to reign in an urge to keep up with the pack.

How can you put the walk-run method into action?

Like we mentioned above, there’s no one set way to break up your run-walk intervals—the best pattern is the one that works for you, says Hamilton. The key, though, is testing it out during your runs before you try it during a race.

That came in clutch for me: During an 18-mile training run, I tried a ratio of three and a half minutes of running to 30 seconds of walking, and found that the high frequency of walk breaks made me feel like I needed to sprint when I finally started picking up the pace again. That ended up seriously fatiguing my muscles, and I finished the run in a slow, painful shuffle. If I had tried that specific run-walk ratio in the race for the first time, my experience in London could have been drastically less fun. (Instead, I chose to go with a 30-to-60 second walk after each mile, which felt really doable.)

In order to be successful, says Hamilton, “You have to embrace the fact that you’re not trying to ‘make up’ for the walk break in the run segments.” I reminded myself of this several times on race-day morning, as I knew that left to my own competitive devices, I would most certainly push the pace during the run intervals and leave myself exhausted.

Relatedly, don’t worry about speed-walking during your breaks, either. The goal isn’t to do a “power walk,” says Galloway, as an elongated stride, especially one that isn’t natural to you, can cause more fatigue and even more injuries, he says. Just walk normally and comfortably.

If you’re using the walk-run method in a race, start out with a more conservative ratio so you can preserve muscle power, says Galloway. Then, if you’re feeling good after about a third or halfway through you can adjust your game plan then. During the last third to fourth of the race, you can make further adjustments and, in some cases, cease your walk breaks altogether—that’s what I did after mile 21.

On the etiquette front, if you’re running in a crowded race, signal to the people around you that you’re about to take a walk break by waving your hand as you move over to one side of the road, says Galloway. This will reduce the chances of you catching the runners directly behind you off guard by suddenly slowing your pace. Then before you start running again, look around to make sure you’re not going to be cutting across or starting right in front of someone, he adds. “It’s all courtesy.”

Lastly, if you’re worried about the stigma of walking during a running race–which I for sure was, until I realized how much it was actually helping me—know that “there’s no shame” in slowing down, says Hamilton. Just remember this: However you choose to complete a distance doesn’t change the fact that you made it to that finish line.