Fitness

The Genius Hack Hilary Duff Uses to Level Up the 12-3-30 Routine

written by KATHERINE CHANG
Graphics by: Aryana Johnson
Graphics by: Aryana Johnson

Hilary Duff needs no introduction. She makes being an actress, singer, and mom of three look easy—and good. While her celeb status affords her the most exclusive workouts, the former Lizzie McGuire star proves she’s relatable when it comes to her sweat sessions. Along with millions of TikTokers, she is a 12-3-30 stan. ICYMI, the viral TikTok workout calls for walking on the treadmill at a 12 percent incline and 3 mph speed for 30 minutes. Duff recently shared with Women’s Health how she ups the ante on the 12-3-30 routine after it became too easy for her. Ahead, her hack and its benefits, plus other ways to level up the 12-3-30 regimen.

Hilary’s 12-3-30 Twist

The suit and puffer vest varieties are not the only ones having a moment. Thanks to Duff, a 12-pound weighted vest is the new “it” accessory, AKA her go-to trick to making the 12-3-30 “hard again.” While it may not be part of the fashion trend, it’s worth donning a weighted vest over your workout ‘fit for its major health perks. Whether you opt for an adjustable one with pockets for adding or removing weights at your discretion or a predesignated version, a weighted vest instantly increases the intensity of your activity of choice, like walking, push-ups, and squats. According to a study, people who added 10 percent of their body weight using a vest burned significantly more calories than those not wearing any weight. Wearing a weighted vest boosts strength-training performance (hello, muscle gains) and helps strengthen heart function, enhance stamina, prevent bone loss, and improve balance. Once you get your new fave workout staple, now comes the best part (besides getting a good sweat): styling your vest (who says you can’t be a fitness and fashion girl?).

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More Ways to Level Up Your 12-3-30 Workout

If a vintage button-up is the only vest style you’re interested in wearing, there are plenty of other approaches to make the 12-3-30 routine more challenging (and interesting). At the same time, it’s more than OK to give it a go at a lower incline, speed, and/or length of time. You call the shots—you know what’s best for your body more than a FitTok trend, after all. If you do want to switch up the viral 12-3-30 workout—either because it’s feeling too routine or you want a challenge—here are a few hacks to try.

Switch up the numbers

Whether you raise the incline, speed, or duration, you can easily take the TikTok-approved workout up a notch sans added weight. Shoot for a 13 percent incline, pick up the speed to 3.5 mph, or test your endurance by going five minutes longer.

Use other forms of added resistance

Weighted vests not your thing, or you don’t want to spend more money on equipment when you already have some at the ready? You can add more resistance and weight to the workout without a vest. For example, add on wrist or ankle weights, or simply hold a light pair of dumbbells (one to five pounds) while walking to add both resistance and work on arm strength.

Work on form

You don’t need to add any weights or change the treadmill settings to further challenge yourself while doing the 12-3-30 workout. Instead, just prioritize form, which will engage more muscles and provide more benefits. For example, try not to use the side or front handrails of the treadmill and focus on pumping your arms with your elbows bent at a 90-degree angle to let your lower body muscles do the heavy lifting.

Try intervals

Instead of a steady-state cardio workout, you can challenge yourself (or personalize to your needs) by turning it into a workout. For example, if you want to make the workout harder, try alternating between walking at a 12 percent and 15 percent incline every other minute, or keep the 12 percent incline and jog at 5 mph for one minute, followed by walking at 3 mph for two minutes. If 12-3-30 is too hard as is (because same), use intervals to work your way up to the 12 percent incline at 3 mph for 30 minutes, or simply make the workout work for you: For example, walk at 6 percent incline for two minutes, 10-12 percent incline for two minutes for the 30 minutes, or start at 1 percent incline, and increase 1 percent every minute until you get to 12 percent, and then work your way down for a “hill” approach. There is so much flexibility and personalization available—the point is to make any workout or routine work best for you.