Is the TikTok-famous '12-3-30' workout effective? Here's what fitness experts think

Over on the fitness side of TikTok, a seemingly simple treadmill workout has become the latest obsession. The 12-3-30 workout was created by lifestyle influencer Lauren Giraldo and she credits it with helping her lose 30 pounds. As Giraldo explained in her video, the 12-3-workout is a 30-minute treadmill workout that relies on a lot of incline. “You put it on an incline of 12, a speed of 3 and for 30 minutes as many times as you can a week,” she explained. However, certified trainer and holistic health coach Dempsey Marks does not recommend jumping right in to this workout. Marks suggests “beginning with a lower level incline and gradually increasing as you build strength and stamina”