I tried the 6-12-25 workout method for building strength with a single kettlebell — here's what happened

Woman holding a kettlebell on her right shoulder against a grey backdrop wearing white crop top
(Image credit: Shutterstock)

Always on the hunt to make my muscle building efforts more efficient, I was feeling excited when I recently stumbled across the 6-12-25 workout method. Well, until I found out what it entails. 

The 6-12-25 method is a bodybuilding training routine where you perform three sets of different exercises for the same muscle group: 6 reps of a heavy compound movement, 12 reps of a moderate weight exercise, and 25 reps of a light isolation exercise to maximize muscle growth.

With isolation and compound moves both offering muscle-building benefits and complementing each other, I knew I was in for a solid workout. Most people would probably suggest using the 6-12-25 method in a gym setting so you can use a mix of equipment for each section of the workout structure.

For example, the barbell is a good tool for performing compound moves with, dumbbells provide a selection of weights for the moderate weight exercises and machines are good for performing controlled lighter isolation exercises with. 

However, I've had a busier week than anticipated and with no time to get to the gym, I decided to try the 6-12-25 method at home using one of the best kettlebells for the full routine. Note, I train with an adjustable kettlebell at home which meant I was able to work with lighter and heavier weights for this workout.

Here's what happened when I tried the 6-12-25 method at home.

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What did my 6-12-25 workout look like?

Focusing on my chest muscles, here's what my workout looked like:

  • Exercise 1: Kettlebell Push Press (6 reps — heavy compound exercise)
  • Exercise 2: Kettlebell Floor Press (12 reps — moderate compound exercise)
  • Exercise 3: Lying Down Kettlebell Flyes (25 reps — light isolation exercise)
  • Repeat three times over

I didn't allow myself any rests between each exercise but I did give myself a one minute rest period between each set. I also spent five minutes after the workout stretching my chest and upper body to help with my recovery and avoid any post-workout stiffness.

I went too easy on the first round

I like a challenge, but I'd been warned that the 6-12-25 method isn't for the faint-hearted. It turns out I took this a bit too seriously.

I kept the weight very manageable for the first section of the method, which involves six reps of a heavy compound exercise. In my case, this was an overhead press, done on each side of my body with my trusty kettlebell.

As soon as I moved on to the kettlebell floor press, I realized I wasn't using enough weight to feel challenged by the workout. Sometimes I do the opposite when I train at the gym, picking a weight that's too heavy for me because I don't want people to judge the weight I'm working with.

While, it was nice not feeling this pressure while doing the workout at home, the 6-12-25 method sets out to exhaust the target muscle group so I needed to increase the workload to get that chest pump going.

a woman performing a kettlebell press on the floor

(Image credit: Shutterstock)

The 25 isolation exercises were tough

I felt strongest during the the six and 12 rep sections of the workout but when it came to keeping the form and effort up during 25 reps of kettlebell flyes on the floor, the chest burn was burning.

This was to be expected. Isolation exercises can feel harder than compound exercises because they target a single muscle group, putting all the stress and workload on that specific muscle without the assistance of other muscles. In the other two exercises, I had other muscles supporting my chest during the moves.

Although I was working with lighter weights, my muscles were fatigued from the earlier sections of the routine and by the end of the 25 reps I needed the break to recuperate before the next set. However, I liked feeling like I was getting a solid chest pump and I liked the efficiency of the workout.

The 6-12-25 method is extremely versatile

I can see why doing the 6-12-25 method at the gym will be more favorable to many as it offers a wide range of weights and machines, allowing you to easily adjust the load for different rep ranges (6, 12, and 25 reps) and in some instances target the muscle groups more effectively.

That being said, I was pretty impressed at how effective using a kettlebell at home was. Since I was using an adjustable kettlebell I had the scope to implement progressive overload into my future 6-12-25 routines, which is essential for muscle growth and strength improvements. 

Plus, the 6-12-25 method is one you can apply to different muscle groups to help build strength, muscle mass, and endurance all over.

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Jessica Downey
Fitness Writer

Jessica is an experienced fitness writer with a passion for running. Her love for keeping fit and fueling her body with healthy and enjoyable food quite naturally led her to write about all things fitness and health-related. If she isn’t out testing the latest fitness products such as the latest running shoe or yoga mat for reviewing then she can be found writing news and features on the best ways to build strength, active aging, female health, and anything in between. Before then she had a small stint writing in local news, has also written for Runners World UK (print and digital), and gained experience with global content marketing agency, Cedar Communications.

Born and raised in Scotland, Jessica is a massive fan of exercising and keeping active outdoors. When at home she can be found running by the sea, swimming in it, or up a mountain. This continued as she studied and trained to become a PPA-accredited magazine journalist in Wales. And since working and living in London, she splits her time between weight training in the gym, trying new fitness classes, and finding scenic running routes. Jessica enjoys documenting this on her fitness-inspired Instagram page @jessrunshere where she loves engaging with like-minded fitness junkies.

She is a big fan of healthy cooking and loves learning more about this area with expert nutritionists she has met over the years. Jessica is a big advocate for building healthy relationships with food rather than building restrictive attitudes towards it. When she isn’t eating or running she also enjoys practicing yoga in her free time as it helps her to unwind and benefits her performance in other sports.