The 12-3-30 Treadmill Workout Got Its Own Study & Revealed This
The 12-3-30 workout has been everywhere. Since first gaining traction on TikTok (where it's racked up over 14 million views), the workout has become one of the most talked-about fitness trends of the past few years. The claim? That this simple incline walking routine helps weight loss.
But here's the thing: Until now, there's been zero peer-reviewed research to back up any of it. That just changed.
A new study from the University of Nevada, Las Vegas, is the first to put 12-3-30 under the scientific microscope, and the results are genuinely interesting. Let's break it down.
What is the 12-3-30 workout, exactly?
If you've somehow missed this one, here's the gist: You hop on a treadmill, set it to a 12% incline, walk at 3 mph, and keep going for 30 minutes. That's it.
The appeal is obvious. It's simple, accessible, and doesn't require you to run (a major selling point for a lot of people). Though don't be fooled, a 12% incline is not easy business.
What the research actually found
Researchers at UNLV recruited 16 participants (7 women and 9 men, all regularly active) and had them complete two treadmill sessions: the 12-3-30 workout and a self-paced running session. Here's the key part: both sessions were matched for total energy expenditure, meaning participants burned the same number of calories in each workout.
The results were telling:
- Taps into fat more effectively: 12-3-30 burned a slighter higher percentage of fat during the workout (~41% vs. ~33% for running). But that's not the same as being better for fat loss.
- Lower carbohydrate use: The flip side? Running relied more heavily on carbs for energy.
- Longer completion time: 12-3-30 took significantly longer to burn the same number of calories as running.
So while 12-3-30 has metabolic benefits, if you're short on time, running gets the job done faster.
So is it better than running?
This is where it gets nuanced, and honestly, the answer depends entirely on your goals.
If your priority is time efficiency: Running wins. You'll burn the same number of calories in less time. For busy schedules, that matters.
If you hate running: This is the real sweet spot for 12-3-30. It's a legitimate workout that doesn't require you to run, and now there's actual research showing it has metabolic benefits. Your knees might thank you, too. Incline walking is generally lower impact than running.
A few things worth noting
Before you overhaul your entire routine, a few caveats:
- This was a small study. Sixteen participants is a solid start for exploratory research, but we'll need larger studies to confirm these findings.
- How your body fuels a workout isn't the same as weight loss. Drawing more from your fat reserves during a workout doesn't automatically translate to losing more body weight over time. Total calorie balance still matters most.
- That incline is steep. A 12% grade is no joke. It's significantly steeper than most people realize. If you're new to exercise or have joint or balance issues, you may want to work up to it gradually.
- The study didn't track long-term outcomes. This research looked at acute metabolic responses during a single session, not weight loss or fitness improvements over weeks or months.
The bottom line
The 12-3-30 workout isn't just social media hype. It's a legitimate exercise option with real metabolic benefits, now backed by peer-reviewed research. When matched for total calories burned, it burns more fat than running.
That said, it's not magic. It takes longer to burn the same calories as running, and how your body fuels a single workout doesn't guarantee weight loss over time.
Here's what this means for you: If you enjoy incline walking, hate running, or want a lower-impact cardio option, 12-3-30 is a solid choice. If you're pressed for time and don't mind running, that's still an efficient way to get your cardio in.
The best workout? The one you'll actually do consistently. And now you have the science to make an informed choice.