Does the 12-3-30 workout work? Experts weigh in on fitness craze

December 18, 2023

The #12-3-30 treadmill workout has become one of the most popular routines of fitness influencers and healthy TikTok girlies with 431.1 million views on TikTok — but does it actually work?

The 12-3-30 workout is fairly simple: set the incline on the treadmill to 12%, the pace to three miles an hour and walk for 30 minutes.

The workout was first posted on YouTube in 2019 by social media influencer Lauren Giraldo and again on TikTok in November 2020, when the video went viral as the #HotGirlWalk craze inspired fitness fanatics to ditch intense workouts and just walk.

“I’m not a runner, and running on the treadmill was not working for me,” Giraldo told “Today” in December 2020, explaining that her formula helped her to shed 30 pounds.

“I started playing around with the settings, and at the time, my gym’s treadmill had [a] 12 incline as the max. The three miles per hour felt right, like walking, and my grandma had always told me that 30 minutes of exercise a day was all you needed. That’s how the combination started.”

This seemingly simple workout is a low-impact exercise, meaning it doesn’t put a lot of strain and weight on your muscles and joints, but does it do anything?

Walking has long been recognized as an efficient workout with a wide array of health benefits to boost both physical and mental health.

The 12-3-30 workout will get your heart rate pumping at about the same rate it would if you went on a jog without straining your muscles or joints.

A study published in the Journal of the American Medical Association found that walking at a brisk pace for 30 minutes a day led to a reduced risk of heart disease and dementia, while more than 10,000 steps per day (the equivalent of 5 miles) may be associated with a lower risk of cancer and death.

The steep incline of the 12-3-30 workout forces your body to expend more energy and therefore burn more calories than walking on a flat surface.

In fact, a study published by the National Library of Medicine found that walking with a 10% incline helped to boost the caloric burn by a significant 32%.

The same study also found that the inclination helps to build muscle in your glutes, quadriceps, hamstrings and calves.

“Walking at a moderate to vigorous pace can improve memory, sleep, cognitive function and help control your weight,” Dr. Robert Glatter, a board-certified emergency medicine physician, told The Post.

“While we encourage people to walk briskly or vigorously to obtain optimal health benefits, walking at even a slower to moderate pace can also reap numerous rewards. You don’t have to do 10,000 steps a day. Walking for just 15 to 30 minutes daily or even just three days a week can result in positive health benefits,” he said, noting that anything is better than constant sitting.

While it may seem like you’re just strolling along, this workout is likely to push you to work up a sweat and should be taken as seriously as other exercise routines.

Experts warn that those who aren’t used to the incline or a rigorous workout should steadily work up to the full 12-3-30 to avoid strain or injury.

They have also warned that this workout should probably be avoided by those with knee problems.

Completing the 12-3-30 workout five times a week allows you to meet the guidelines set by the U.S. Department of Health and Human Services Physical Activity Guidelines suggesting adults get at least 150 minutes of moderate-intensity activity a week, or at least 75 minutes of vigorous-intensity activity a week.

However, the department also advises that adults should include muscle-strengthening activities like lifting weights or doing push-ups at least two days each week.

“It’s important to develop and use different muscle groups,” Dr. Selina Shah, MD, board-certified sports medicine and internal medicine private practice physician, told Health.

For those who do want to try the 12-3-30 workout, TikToker Allie Bennett has the perfect playlists for you. Jumping on the #HotGirlWalk trend, Bennett has gone viral sharing her #TreadmillStrut-inspired tunes on Spotify and TikTok.

Many of her playlists are about 30 minutes long to perfectly sync up your steps to the workout.

“It was just kind of something to reframe exercise in my mind,” Bennett, widely credited with starting the trend, told The Post.