I asked a walking coach how she felt about the 12-3-30 walking workout—here’s why she never recommends it to her clients and what you should be doing instead

I’m always on the lookout for trending walking workouts, and when I noticed the 12-3-30 routine gaining popularity on social media again, I decided to get a professional's opinion. I ran it past walking coach and certified personal trainer Joyce Shulman—and her response didn’t surprise me.

The 12-3-30 treadmill-based walking workout involves walking at a 12% incline at 3 miles per hour for 30 minutes.

My colleague tried the 12-3-30 plan for a month and found her legs got stronger, although the steepness of the incline was a shock at first. They still preferred it to treadmill running, though.

But Shulman was less than enthusiastic. “In America, we like to go hard and see how much we can do, but then people either burn out, get injured or think ‘Why bother?’,” says Shulman.

This 12-3-30 walking workout, she argues, is an example of this. Its high incline pushes people to dive in at the deep end, which can increase their risk of injury if they're not used to it.

“One of my reservations is that incline walking can put a lot of strain on your Achilles tendon and calves,” says Shulman. “If you're not accustomed to it, there's so much stress, stretch and flex that goes with walking on an incline, so I always encourage people to build up incline more slowly.

“One issue with some of these trends is they don't incorporate a progressive increase.”

I’ve spoken to a lot of experts about progressive overload training, but was surprised to learn it applies just as much to walking. Even increasing your step count should be done gradually. Shulman agrees that whether you’re increasing the distance, speed or incline, your body needs time to adapt.

Going from walking on a flat surface to a 12% incline for 30 minutes is a big leap, and one that can put your musculoskeletal system under stress.

What Shulman recommends instead

Go for a walk outside instead (although in certain cases it’s better to walk on a treadmill).

For one, there are slightly different physical demands. “[Outdoor walking] adds benefits for balance and ankle mobility, and is really good for fall prevention,” says Shulman.

“There are additional benefits that you get from walking in nature, particularly for your mind and mood that you're not going to get from marching on a machine,” she says.

That said, Shulman says that if a treadmill workout is all you can manage today and is the difference between a day with no movement and a day with some movement, then you should absolutely go for it.

Just follow the rule of progressive overload—increasing one variable by no more than 5-10% over the course of a week. That way, you’re more likely to stick with the it and stay injury-free.

Joyce Shulman

Joyce Shulman is a certified personal trainer and walking coach focused on women, wellness and longevity.  She has taken the TEDx stage to talk about the power of walking together to help combat loneliness and has written two books: Walk Your Way to Better: 99 Walks That Will Change Your Life and Why Walk?: Discover the Transformative Power of an Intentional Walking Practice.

Shulman is a representative for topical pain relief brand Aspercreme.

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