What Is the 12-3-30 Workout and What Are Its Benefits?

New year, new workout? Sometimes, a fresh way to train is exactly what you need to restore motivation to hit the gym and fend off winter blues.

If you’ve scrolled through social media accounts recently for fitness inspo, it’s possible you saw someone talking about the 12-3-30 workout. The accessible treadmill routine continues to be a hit among many because it ups your heart rate without demanding a lot from your body.

Ahead, two fitness professionals share the potential benefits and drawbacks of doing this trending aerobic workout on the regular.

What is the 12-3-30 workout?

“The viral 12-3-30 workout is a treadmill workout where you walk at 3 miles per hour at a 12 percent incline for 30 minutes,” says personal trainer Tara De Leon, RSCC, CSCS. She adds that 3 miles per hour (about 20 minutes per mile) is an average walking pace, but it’s the incline that makes things spicy.

Social media influencer Lauren Giraldo first posted this workout on YouTube in 2019, but it didn’t take off until she posted a TikTok video in 2020. In that video, she says the workout helped her become less intimidated by the gym and boosted her motivation. She does this workout about five days a week, she says—and according to people in the comments, the workout isn’t exactly a walk in the park.

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4 benefits of the 12-3-20 workout

The benefits of walking are immense, from supporting your overall physical health to boosting mental well-being. Here’s what De Leon and David Chesworth, ACSM-CEP, an exercise physiologist and program director at Hilton Head Health Wellness Resort & Spa, say this workout can offer your body and mind.

1. It supports heart health

Doing some kind of aerobic exercise regularly is essential for a healthy heart. “Getting [at least] 150 minutes of cardiovascular exercise per week is recommended by the American Heart Association, and this workout fits in perfectly,” De Leon says. It’s true, if you did this workout five times a week, you’d hit that minimum recommendation.

In general, baking cardio sessions into your workout regimen can help prevent several chronic conditions later in life. Research suggests that doing moderate-intensity exercise each week can reduce the risk of several chronic conditions, including cardiovascular disease and diabetes¹.

2. It’s safe, but effective

If you’re new to the gym or making a comeback after a substantial break, getting injured or straining a muscle is a real concern. But that’s what makes the 12-3-30 workout so great: It’s essentially a challenging walk.

“The benefit of a workout like this is that it provides a low-impact way to perform a moderate- to high-intensity routine,” Chesworth says. Another perk? You don’t need any other equipment other than a treadmill and a pair of walking shoes. You also don’t need a coach or trainer to supervise you as you might when lifting heavy weights. “There’s very little thinking involved [with this workout] and there are very few ways it can go wrong.”

3. It supports joint health

Your joints are areas in your body where two bones connect so they can move. Engaging in regular physical activity helps your joints stay mobile because it stimulates the production of synovial fluid, which is key for your bones to move past one another smoothly. The 12-3-30 workout can help your joints stay flexible and lower your risk of injury while working out.

“Motion is lotion, rest is rust,” De Leon says. “Regularly moving your joints through a functional range of motion will help lubricate them and improve mobility, which can help reduce stiffness or pain.”

4. It may improve mental well-being

Breaking a sweat does wonders for your mind. One 2024 meta-analysis² in Acta Psychologica found that moderate physical activity was linked to significantly lower depressive symptoms compared to those who didn’t work out. As De Leon mentions, cardio can help increase the production of feel-good endorphins which can help quell anxiety and stress.

“I can’t emphasize enough how important it is to meet yourself where you are today.” —David Chesworth, ACSM-CEP

3 drawbacks of the 12-3-30 workout

There’s no such thing as a magic bullet workout. Ideally, you’ll want to do a variety of different exercises and movements weekly to help support your muscles and bones in multiple areas of your body.

1. It’s an incomplete workout

“While this is a great way to get your cardio in, this is not an end-all-be-all routine,” Chesworth says, adding that you should also focus on strength and mobility exercises. Establishing a well-rounded workout routine is the way to go, he says.

2. It’s not great for knee and back injuries

In general, it’s always a good idea to clear a new workout with your physical therapist or doctor, especially if you have a history of injuries.

“Walking at a steep incline with back or knee injuries may not be the best idea,” Chesworth says. Instead, he suggests taking the 12-3-30 approach to an elliptical, recumbent bike, arm ergometer, or another cardio machine that won’t put as much pressure on your knees and back muscles.

3. It can be monotonous

De Leon says it best: “Walking on a treadmill can be boring, so cue up your favorite workout playlist and get stepping.” But if this routine becomes unenjoyable, that can discourage you from staying consistent with your workouts.

“If it bores you, it probably won’t stick,” Chesworth says. “It doesn’t matter how valuable the benefits of exercise are if you don’t actually do it. Finding exercises that are realistic to accomplish and that make you want to continue is the best combination for long-term results.”

How to get started with the 12-3-30 workout

Both Chesworth and De Leon provide tips on how you can implement the 12-3-30 workout into your routine.

1. Don’t knock it ’til you try it

Chesworth recommends kicking any preconceived thoughts or judgements to the curb. Head into this workout with a beginner’s mindset, as “this approach will give you a more objective way to discover if this routine is right for you.”

2. Start slow

“If you’re new to exercise, you might need to start out a little easier,” De Leon says. “Try going for 5 or 10 minutes to start, or reducing your speed. Remember, you want it to be challenging, but doable.”

3. Hydrate

Replenishing your body with water and electrolytes is key during cardio workouts. “Drink 20 ounces of water about two hours before your workout, then aim for another 8 ounces every 10 minutes of exercise,” De Leon says.

4. Don’t skip your cooldown

Just because you’re walking doesn’t mean a cooldown isn’t necessary, according to De Leon. “Don’t stop your treadmill cold turkey—bring your incline back to zero and be sure to slow your pace down for a couple of minutes before you hop off,” she says. Consider doing some static stretches afterward to get ahead of muscle tightness.

Is the 12-3-30 workout right for you?

If your doctor or physical therapist says you should avoid high-impact exercises like running and circuit training, the 12-3-30 workout might be a great fit for you—especially if you don’t have knee or back issues. Not to mention, it’s easy to scale up, Chesworth says. “Is the 12-3-30 workout too easy? How about trying the 15-4-40,” he says.

For more seasoned gym-goers, this workout may not be enough for them and that’s okay. No matter how you do your cardio each week, it’s important that you also make sure you’re also squeezing in strength workouts to help support strong muscles and bones.

Remember, not every day is the same. One day the 12-3-30 workout will feel like a breeze, and the next, it may feel really difficult. “I can’t emphasize enough how important it is to meet yourself where you are today,” Chesworth says. “The biggest barrier to change is lack of action. If the action is too big, it won’t happen. Change the action to make it doable.”