What Is the 12-3-30 Workout? And Does It Work?

Unlocking a higher level of fitness might come down to this simple code: 12-3-30. Those three numbers set the basic ground rules for a treadmill workout that’s gathering plenty of breathless buzz on TikTok.

The 12-3-30 walking program works like this:

• Raise your treadmill’s incline level to 12%.
• Dial up the pace to 3 mph (miles per hour).
• Walk for 30 minutes.

Easy to follow, right? Now the bigger question: Is it worth trying? To answer that, let’s turn to exercise physiologist Katie Lawton, MEd.

Origins of the 12-3-30 workout

Credit for the 12-3-30 program goes to Lauren Giraldo, a social media sensation with a sizeable band of followers. She first shared the workout on YouTube in 2019. It exploded in popularity as a TikTok trend a year later.

Giraldo says the workout helped her shed 30 pounds and transform her body. She posted before and after pics as evidence, too.

Millions of views later, the workout qualifies as a runaway success.

How to start the 12-3-30 treadmill program

Let’s begin with this basic fact: Don’t expect the 12-3-30 workout to be a walk in the park. (Well, unless it’s a very hilly park.) “It’s definitely on the harder side,” says Lawton. “That’s a steep incline — and it’ll really feel like it’s over 30 minutes.”

So if you’re using this program as a first step to establish an exercise routine, take it slowly. Tweak the incline, pace and treadmill time numbers to meet your fitness level.

“Maybe start by walking at a flat incline for 30 minutes to see if that’s obtainable,” says Lawton. “Or put the incline at 5% to see how you do. Maybe slow down the pace or go for less time. See what your body can tolerate and build from there.”

Basically, use the 12-3-30 target as your goal or general framework: “You don’t have to start there,” says Lawton. “Make adjustments based on your health, your fitness and how you’re feeling.”

(It’s worth noting that Giraldo, who is in her early 20s, admitted to early struggles with the program. She said it took her time to go the full 30 minutes and get comfortable doing the workout.)

Training tips to boost your workout

If you’re going to try the 12-3-30 workout, keep these suggestions in mind.

1. Invest in a good pair of walking shoes that provide proper support for your feet. (Learn how to pick out the right pair from a physical therapist.)
2. Try to avoid holding onto the treadmill while walking, as it reduces the benefits of the workout. “If you feel like you need to hang on, you probably should consider changing the incline or speed,” notes Lawton.
3. Use good form, with a bit of a lean to your body as you stride. “You want a really good arm swing, too. Use the momentum of your arms to help propel yourself forward,” says Lawton.

Learn how to get the most out of your treadmill workout.

Can the 12-3-30 program help you lose weight?

Given the treadmill incline level, this workout routine will torch calories like a five-alarm fire.

The reason why is simple: Walking uphill makes your body work harder on every single step, pushing up the cardio intensity, says Lawton. The calorie burn at a 12% incline is nearly double what it would be walking on a flat surface.

Building the 12-3-30 program into your exercise routine five days a week would add up to 150 minutes of heart-pounding activity. That could go a long way toward dialing back the number popping up on the bathroom scale.

(The American College of Sports Medicine recommends 200 to 300 minutes of exercise per week for weight loss.)

However, Lawton cautions about basing a weight-loss and fitness plan entirely on the 12-3-30 workout. She suggests balancing the cardio with some strength training to work different muscles.

Eating healthy is also key if you’re looking to shed pounds. “You cannot out-exercise a bad diet,” notes Lawton.

Is the 12-3-30 workout worth trying?

As with many things borne through social media, there’s a gimmicky feel to the 12-3-30 plan. The workout, however, offers true fitness benefits — especially if combined with other healthy lifestyle habits.

“Whatever gets people to do more exercise is great,” says Lawton. “Just watch what you’re doing and take it slow when you start.”