Skip the treadmill! This 20-minute HIIT workout burns fat and builds muscle

Treadmills are a great way to get in your daily dose of cardio, but walking or running to nowhere isn’t always a very thrilling idea.

For fitness enthusiasts who need a little cardio variety, HIIT (or high-intensity interval training) has long been a popular choice. According to a study in Biology of Sport, HIIT — which pairs short exercise intervals with even shorter rest intervals — has been shown to improve athletic performance, body composition, and cholesterol levels.

I’m due with a baby any day now, and my cardio workouts for the last nine months have been less than exciting. I desperately needed a break from my usual treadmill walks, so I decided to give fitness trainer Oliver Sjostrom’s recent “all-levels” HIIT workout a try.

Exercising during pregnancy comes with loads of benefits, but you should still check in with your medical team before breaking a sweat. If you’re new to working out, consider meeting with a personal trainer to learn the proper form for basic movements.

How to do Oliver Sjostrom’s 20-minute HIIT workout

You’ll just need a yoga mat and a little bit of space for Sjostrom’s workout, which consists of 20 exercises done for 45 seconds each with 15 seconds of rest in between.

The exercises are:

• Step out jack + small squat
• Squats
• Knee to elbow + four squat pulses
• Walkouts
• Squat + reach
• Plank to pyramid
• Plank step outs
• Knee push up to push back
• Split squat (each leg)
• Step back + clap
• Plank shoulder + knee taps
• Simple squat + knee up
• Superman reach
• High plank leg lifts
• Crunch
• Russian twists
• Bent leg raise
• Glute bridge
• Stand + punch

20 Min Fat Burning Cardio HIIT Workout at Home (No Equipment, No Repeats) - YouTube

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Here are my takeaways from Sjostrom’s routine.

The moves were all low-impact...

HIIT is usually associated with exercises like burpees, squat jumps, and butt kicks, but all of the moves in Sjostrom’s workout were low-impact, no-jumping movements.

At nine months pregnant, I really appreciated keeping my feet on the floor the whole time. You don’t have to be pregnant to reap the benefits of low-impact exercise, though — staying true to Sjostrom’s “all-levels” claim, these types of movements are much more accessible to a wider range of fitness levels and abilities.

If you’ve just started to workout consistently, low-impact exercises can be a great introduction to a well-rounded cardiovascular workout. They’re also a great option for those with muscle, bone, or joint injuries.

...but they still got my heart racing

“Low-impact” doesn’t mean “easy,” so I wouldn’t ever classify this workout as a total breeze. Burpees and squat jumps may have been absent from the program, but you wouldn’t know that looking at my Apple Watch — my average heart rate came in at 145 beats per minute, which is around what I’d get with an intense elliptical workout or light jog. I should mention that pregnancy does increase your heart rate significantly, however, I think this workout would have packed a cardiovascular punch even if I wasn’t expecting.

The great thing about HIIT is that you can work at whatever speed you’d like. If you’re regularly active and want a challenge, you can move quickly during each exercise. If you’re a beginner, you can go a little slower.

It’s exactly 20 minutes

After doing my fair share of YouTube workouts, I’ve come to learn that “20 minutes” may mean 22 minutes, 25 minutes, or sometimes even longer. Sjostrom keeps things running right on time — if you’ve got a tight schedule, rest assured that you’ll be wrapped up and ready for a shower in exactly 20 minutes.

Some workouts tend to go longer than advertised because instructors throw in a warm-up and cool-down too, and I always think that’s worth the extra time. Since there’s no warm-up or cool-down in Sjostrom’s routine, I’d recommend doing something on your own — even if it’s just a few leg swings or hamstring stretches.

You’ll need a decent level of core strength

While I generally agree with this workout’s “all-levels” classification, a lot of the moves do require a good base level of core strength.

There are several exercises done in a plank, and a few of them are done right after the other. If you can’t hold a standard plank for at least 45 seconds, you may need to take a mid-interval break or modify your form.

My core strength is pretty compromised at the moment, so I had to adapt several of the exercises. A second trainer joined Sjostrom for the workout, so it would have been helpful if she showed modifications for some of the more challenging movements. This would have really opened this workout up to “all levels.”

With that being said, I’d still give this workout a go — even if you’re a newbie. You can always revisit it in a few months to see how much you’ve progressed.

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