When I started down this rabbit hole of looking for evidence backing up kettlebell training, I figured it wouldn’t be that hard. After all, the blasted things have been around for centuries. There are pictures of old-time strongmen like Eugene Sandow hoisting the things.
Anything that old and that linked to historic physical culture should have a lot of research behind it by now, right?
Eh…not so much.
Don’t get me wrong. There are studies. A search for “kettlebell” at Google Scholar yields almost 3,200 hits. While that’s a lot, some of those are citations and from Google Books and such. Not all of them are actually research papers.
If you go over to ResearchGate where you’ll weed out of a lot of that, you get a lot of hits that sure do touch on kettlebells, but they’re not directly related training for the average person.
Searching for “Kettlebell Strength” brings up less than 60 (the site doesn’t really give you a total count of studies). “Kettlebell hypertrophy” brings up a much easier number: zero.
In other words, there’s are a lot of studies that look at kettlebells, when it comes to applicable research, well…there’s not a whole lot of studies out there. There’s almost nothing, to be honest.
Not only that but of the studies that exist, most suffer from a painfully small sample size. That’s not exactly forbidden in science, but it does introduce the possibility of statistical “noise” into the studies. (More on this another day.)
Most of this started because I wanted to know exactly what muscles are worked in various kettlebell movements. Then it spawned off into the weeds of just how much could you get out of the kettlebell.
Yet after only a short period of time, I’m finding part of the real trouble.
You see, most of the studies on strength training has been around more traditional movements and equipment here in the west. That means barbells and dumbbells.
That’s not really surprising.
After all, exercise scientists are people who are drawn to both science and fitness. As things currently stand, that means most are people who train/trained with barbells, dumbbells as well as engaged in more traditional forms of conditioning.
They’re going to find questions with those implements to explore far easier if they’re using those implements. It’s easy to look at the equipment you know and want to know more.
But when you don’t do kettlebells, things get a little tricky.
So that’s led me to wonder how to approach things going forward. I want to base my training in scientific evidence, but there isn’t really all that much. That means I have to get a little creative.
You see, there’s some information we already have, it’s just not kettlebell-specific.
For example, muscular hypertrophy. There’s absolutely no research showing kettlebells can be used for hypertrophy.
However, over at Caveman Training, it’s kind of a no-brainer:
Yes it’s possible, but you have to change the way most people work with them, you have to follow the same program as bodybuilders do, heavy and slow reps paired with a strict diet.
The staple of bodybuilding exercises are front squats, shoulder presses, chest presses, rows, carries, isometrics, and curls. Nothing different between time under tension or time under tension, weight equals weight, you just need to know how to use it, those that say otherwise just don’t know.
Honestly, it makes sense. While there’s no research into this, there’s also little reason to believe that you can’t maximize muscular hypertrophy through kettlebell use in more traditional bodybuilding-like exercises.
Of course, that’s kind of a shame.
You see, kettlebell guys are never going to look like powerlifters or bodybuilders. Sorry, they’re just not.
For me, that’s fine. After I finish losing the weight, I probably won’t mind putting on some muscle, but I’m also not really sweating it either. Yet I also know that my goals aren’t everyone’s goals, nor should they be.
Once upon a time, I was technically underweight. That wasn’t just me saying that; it was my doctor. I was medically diagnosed as being underweight.
Back then, I trained for size. I wanted to take my naturally lean physique and add some muscle to it. If someone had told me I was stupid for worrying about adding muscle, I’d have thought they were an idiot.
And, unlike most people I thought were idiots when I was 17, I’d have been right about them.
So some people will want to build muscle and the kettlebell may be the only tool they have. Well, look at the research. There’s very little of it that would tell you that it’s impossible for you to gain muscle using a kettlebell.
This isn’t unique to hypertrophy, either.
No, it’s a struggle with kettlebells in general.
For example, one of the more interesting kettlebell exercises for me is the kettlebell high pull. Basically, you do a one-armed swing, then pull it back as it approaches shoulder height. Once you’ve pulled all the way back, you then push out like a bench press and allow the weight to drop.
In theory, this exercise should work not just the quads, hamstrings, abs, and obliques, as we’ve seen, are worked in the swing, but also the lats, pecs, biceps, and triceps as well as the anterior and posterior deltoids.
I mean, if so, this is probably one of the most powerful movements one can engage. It’s a near-total upper body resistance movement.
Yet can I definitively state that it trains those muscles?
From an educated standpoint, maybe. After all, you are moving weight in a plane similar to not just the swing, but also a row and the bench press when you consider the kettlebell’s relation to the body. With sufficient weight, why wouldn’t all those muscles get solid training?
This is, unfortunately, how we get such widely divergent views on just what is trained by which kettlebell movement.
After all, is the work performed by the pectoralis major sufficient in the “punching out” movement pattern to stimulate muscular adaptations? Some, such as myself, seem to believe they do. I suspect others disagree. Yet all we can do is debate the issue based on our experiences and knowledge base on what a study should find if it ever bothered to look.
For the record, this isn’t me admitting defeat. There are studies being completed all the time. For example, for just 2019, Google Scholar presents 36 listings, which means studies are being done.
The trick is them being the right studies, and that’s easier said than done.
I tell you, though, if I ever get stinking rich, I’m going to create a research institute that will conduct the most in-depth studies humanly possible, studies with (hopefully) a large sample size that will really get to the answers we all want and need about fitness and nutrition.
A guy can dream, right?