I just answered an email the other day about it from a reader.
“At 70 kgs weight and 85 grams of protein a day, can I develop muscle mass and improve my strength using kettlebells? How would I feel improvement in my muscle mass and strength?
“Will KB workouts alone be sufficient to build muscle mass and strength? There are some very conflicting insights on it on online forums.”
First, here’s what I said to this gentleman -
“Yes you can increase strength, but muscle will be more difficult . The current recommendation for increasing muscle is 1.6g/kg of bodyweight. How would you notice improvement? You wouldn't. You'd quantify it through your training log, a tape measure, and body build composition measurements.
Yes. Resistance develops muscle and strength, regardless of the equipment . The key is knowing how to organize your program to do so. Many, if not most people don't know how to do this - especially with kettlebells, so they say "kettlebells don't build muscle" or "you can't get strong using kettlebells" or "kettlebells are an endurance / conditioning tool.””
Second, before we get to the “not knowing how design” part we have to address the fact that there are many different explanations for muscle growth.
At the very least, we have the following:
Mechanical Tension and Mechanotransduction: Mechanical signals from resistance exercise are primary stimuli for hypertrophy. These signals activate mechanotransduction pathways, which convert mechanical stress into cellular responses, triggering protein synthesis and muscle growth (Wackerhage et al., 2019; Bamman, Roberts and Adams, 2018; West et al., 2010).
mTORC1 Signaling: mTORC1 is a essential regulator of muscle protein synthesis and ribosomal biogenesis, facilitating the growth of muscle fibers. It is activated by mechanical overload and nutrient availability, particularly amino acids (Wackerhage et al., 2019; Roberts et al., 2023; Schiaffino et al., 2020).
Ribosomal Biogenesis: The boost in ribosome production supports the muscle's ability to synthesize proteins, fostering hypertrophy (Roberts et al., 2023; Bamman, Roberts and Adams, 2018).
Hormonal and Growth Factor Influence: While systemic hormones like growth hormone and testosterone have limited direct impact post-exercise, local growth factors such as IGF-1 contribute to muscle adaptation and growth (West et al., 2010; Schiaffino et al., 2020).
Metabolic Stress: Metabolic stress from resistance exercise, such as that induced by blood flow restriction, can also drive hypertrophy, although the exact metabolites involved are not well characterized (Wackerhage et al., 2019; Schoenfeld, 2010).
Third, the kettlebell, unlike the barbell or a dumbbell, has at least one unique property:
The offset handle.
The fact that the kettlebell lays on the back of your wrist or spins inside your palm and around your hand, landing on the back of your wrist…
And that requires your muscles and joints to work harder , increasing the tension both on your joints and muscles. Which, according to at least some of the aforementioned “hypertrophy mechanisms,” supports muscle growth.
Plus, the fact that you can drive the kettlebell through your legs and quickly elongate the muscles of your posterior chain (called “fast eccentrics”) and engage your abdominal musculature making it harder to breathe…
Also triggers a few more of those “hypertrophy mechanisms” depending on how you program your workouts.
Which actually brings us to “how to program your kettlebell workouts for muscle growth.”
I’ve discovered there are 3 straightforward, but surefire ways:
1- Program off a 5RM using the combined lifts, like the Clean + Press and Front Squat.
2- Program off a 10RM, also using some of the combined lifts, like the Clean + Press or Clean + Push Press.
3- Using Double Kettlebell Complexes and Chains like these.
Again, at the end of the day, it’s not that complicated to build muscle using kettlebells. You just have to be
A - Willing to do the work.
B - Be intentional about the work you’re doing.
Stay Strong,
Geoff Neupert.