You may have noticed people talking about the viral “12-3-30″ workout on social media recently, or seen the workouts believers for yourself at the gym (they’ll be the people walking at a very high incline on the treadmills).

The workout, created by social media influencer Lauren Giraldo, has received a lot of attention lately for its simplicity and results. It involves walking for 30 minutes on a treadmill at a 3 mph pace and on a 12% incline.

“I’m not a runner, and running on the treadmill was not working for me,” Giraldo told TODAY. “I started playing around with the settings, and at the time, my gym’s treadmill had 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.”

Giraldo first shared the workout on YouTube in 2019, but it continues to grow in popularity on TikTok. The video has amassed over one million views on YouTube and 12.3 million views on TikTok. What’s more, the workout has inspired thousands of viewers to make their own 12-3-30 experience videos, with titles like “How 12-3-30 changed my life.”

“I do this every single day or at least I try to do it every single day,” Giraldo said of the workout in her YouTube video. “Before I used to get very overwhelmed when I walked into the gym. This made it really easy to just come in and do the same thing every day.”

However, this isn’t a workout you should jump right into, Dr. Dennis Cardone, osteopathic sports medicine specialist and chief of primary care sports medicine at NYU Langone Health, told TODAY.

“The problem is people don’t think that walking is a stressor. They think ‘what’s the big deal using an incline? I’m only walking.’ But it really is a big stressor: low back, hamstring, Achilles tendon, knee, plantar fascia … these are the areas where we see some significant injury related to inclining a treadmill,” he said. “As a general observation, anytime anybody begins or changes a workout or adds something like an incline, they have to follow the rule to do it slowly, otherwise they are certainly at significant risk for an overuse injury.”

According to Cardone, the key to getting the results you want from any exercise is to find a program you can stick with. That means it not only has to be safe, but it also has to be enjoyable to avoid burn out, “not just physically, but mentally.”

About the Author