Hilary Duff Likes To Take Her “12-3-30” Workouts To The Next Level

The “12-3-30” workout is one of the biggest fitness trends of the past few years. This TikTok-viral treadmill routine has become the go-to way to sweat for millions of folks — including Hilary Duff.

The How I Met Your Father actor jumped on the 12-3-30 bandwagon along with everyone else, but eventually reached a point where the routine became too easy. That’s when she had to get creative.

In a recent interview with Women’s Health, Duff admitted to adding a little something extra to the workout in order to take the walking routine up a notch.

The 12-3-30 Workout, Explained

If you’re not familiar, the 12-3-30, created by fitness influencer Lauren Giraldo, took off on TikTok in 2021 — where it’s since racked up over 340 million views.

To do the workout, simply hop on a treadmill, set the incline to 12% and the speed to 3 mph, and walk for 30 minutes. It sounds easy, but it’s only a matter of time before the sweat sets in.

As you get those steps in, you’re building cardio endurance while strengthening your legs and glutes.

Hilary’s 12-3-30 Hack

When speaking to Women’s Health, Duff mentioned that she’s a big fan of the 12-3-30, but noted that it eventually felt too easy — so she began wearing a 12-pound weighted vest for more of a challenge.

By strapping more weight to her body, Duff instantly increased the intensity. Just like a set of ankle weights will make your leg day routine more difficult, a weighted vest tires your muscles faster and increases your cardio output while you walk. It also helps to improve your balance.

Other Ways To Tweak The 12-3-30

There are plenty of ways to modify the 12-3-30 to make it both easier and harder. If the 12% slope is too much, bring it down to 6% — or whatever feels more doable — and stick to that. With time, you should be able to slowly build up to the full 12%.

To make the regimen more approachable, you can try doing it in intervals where you walk for one minute at 12%, take the incline down flat for the next, and repeat the up-and-down process for the full half hour.

You could copy Duff’s weighted vest hack, or strap on wrist and/or ankle weights for added resistance if you’re down for a challenge. Or, to increase the workout’s intensity, try walking at a faster speed.

Whichever route you take, be sure to avoid hanging onto the handrails or the front of the treadmill, as that takes your legs out of the equation. Instead, let your arms pump by your sides with your elbows bent at a 90-degree angle. This will put the emphasis back on the big muscles of your lower body while also boosting your cardio.

Duff’s Other Fitness Faves

Duff is quite the fitness buff. When she isn’t walking on the treadmill in a weighted vest, the mom of three previously told Bustle that she loves playing tennis and dancing with Tracy Anderson. She’s also a fan of taking heated HIIT Pilates classes at Silver Springs.

“There’s nothing better than the way [that workout] makes your skin feel,” she told Women’s Health. “You feel like you got rid of what you needed to get rid of, and then your skin just feels so nice.”

Weightlifting is another way she likes to get her sweat in. “Lifting weights, as a woman, is really important,” Duff went on to say. “It’s important for your bones.”

Studies referenced:

Gaffney, CJ. (2022). Weighted vests in CrossFit increase physiological stress during walking and running without changes in spatiotemporal gait parameters. Ergonomics. doi: 10.1080/00140139.2021.1961876.

Roghani, T. (2013). Effects of short-term aerobic exercise with and without external loading on bone metabolism and balance in postmenopausal women with osteoporosis. Rheumatol Int. doi: 10.1007/s00296-012-2388-2.

Tantiwiboonchai, N. (2011). A comparison between the effects of the walking exercise with and without weighted vests on bone resorption and health-related physical fitness in the working women. J Med Assoc Thai. PMID: 22338922.