I'm a fitness trainer with over a decade of experience but this new workout style has cut my exercise time in half

The concept of hybridized fitness has been gaining momentum, thanks to its efficient combination of strength and cardio.

As a certified personal trainer and someone who enjoys exercise, efficiency has never been my top priority—I’d rather take my time than rush and risk an injury. However, with a full schedule recently leaving me short on time I decided to try Kathrin Kunz’s 30-minute hybrid fitness routine.

Kunz packs a lot into a relatively short time frame, targeting nearly every muscle group in the body. To tackle her program, you’ll need a mat, two moderately-heavy dumbbells and a little bit of courage.

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How to do Kathrin Kunz’s hybridized workout

Kunz’s workout is structured similarly to a HIIT (or High Intensity Interval Training) session, with timed exercise and rest intervals.

After a five-minute warm-up, you’ll work for 40 seconds and rest for 15 seconds, completing each of the two circuits of four exercises twice. Kunz follows this with a cardio-based finisher of 12 exercises performed for 30 seconds and 15 seconds of rest each. The routine finishes with a five-minute cool-down.

Kunz uses two 7.5 kilogram/16.5 pound dumbbells for the workout. I used my 5.4 kilograms/12 pound dumbbells.

What I found doing a hybridized workout

It took longer than 30 minutes

Calling this a 30-minute workout is somewhat misleading—by the time you’ve completed the warm-up, all the circuits and the cool-down it’s over 40 minutes of exercising. However, many workouts advertised as 30 minutes don’t feature a warm-up or cool-down so it’s helpful that Kunz has included them.

Even with the extra 10 minutes, I still felt like I got a well-rounded workout in significantly less time than usual. I’ll likely re-visit this routine when I’m short on time.

Some exercises were difficult

I’ve been working out consistently for almost 20 years, so I feel comfortable doing most exercises. However, even with my background, some of Kunz’s movements were challenging—particularly the alternating table reach in the warm-up and the one-handed mountain climber in the cardio finisher.

This highlights one of my biggest pet peeves with fitness influencers: failing to show modifications. In the workout’s description, Kunz says you should "feel free to modify some exercises if needed" but doesn’t show how to do this. With a second instructor in the video, it would have been ideal for them to demonstrate alternative options, making the workout more accessible to a wider range of fitness levels.

It’s a good benchmark workout

Kunz’s workout is challenging and not easy for beginners. If you’re new to exercise, I would revisit this program once you’ve built some more experience.

One of the great things about YouTube workouts is that you can use them as a benchmark for your progress. So even if you can’t complete this workout now, try again after building some strength and endurance and you may surprise yourself with how much you’ve improved.

If you're just starting out, I'd recommend doing something like this HIIT workout for beginners or a beginner's bodyweight workout instead.