I just addressed an email the other day about it from a reader.
“At 70 kgs weight and 85 grams of protein a day, can I build muscle mass and improve my strength using kettlebells? How would I notice improvement in my muscle mass and strength?
“Will KB workouts alone be enough to increase muscle mass and strength? There are some very conflicting insights on it on online forums.”
First, here’s what I explained to this gentleman -
“Yes you can develop strength, but muscle will be harder . The current recommendation for increasing muscle is 1.6g/kg of bodyweight. How would you notice improvement? You wouldn't. You'd measure it objectively through your training log, a tape measure, and body composition measurements.
Yes. Resistance increases 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 program ” part we have to address the fact that there are many different mechanisms for muscle growth.
At the very least, we have the following:
Mechanical Tension and Mechanotransduction: Mechanical signals from resistance exercise are key stimuli for hypertrophy. These signals activate mechanotransduction pathways, which convert mechanical stress into cellular responses, promoting 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 increase in ribosome production supports the muscle's ability to synthesize proteins, aiding hypertrophy (Roberts et al., kettlebell 2023; Bamman, Roberts and Adams, 2018).
Hormonal and Growth Factor Influence: While systemic hormones like growth hormone and testosterone have restricted direct impact post-exercise, local growth factors such as IGF-1 play a role in muscle adaptation and growth (West et al., 2010; Schiaffino et al., 2020).
Metabolic Stress: Metabolic stress from resistance exercise, such as that triggered by blood flow restriction, can also encourage 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, does have at least one unique property:
The offset handle.
The fact that the kettlebell sits on the back of your wrist or turns inside your palm and around your hand, landing on the back of your wrist…
And that requires your muscles and joints to exert more effort , increasing the tension both on your joints and muscles. Which, according to at least some of the aforementioned “hypertrophy mechanisms,” creates muscle growth.
Plus, the fact that you can drive the kettlebell through your legs and quickly extend the muscles of your posterior chain (called “fast eccentrics”) and tighten your abdominal musculature making it tougher to breathe…
Also activates a few more of those “hypertrophy mechanisms” depending on how you program your workouts.
Which actually gets us to “how to program your kettlebell workouts for muscle growth.”
I’ve discovered there are a few basic , but reliable ways:
1- Program off a 5RM using the paired lifts , like the Clean + Press and Front Squat.
2- Program off a 10RM, also using some of the double 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 hard to build muscle using kettlebells. You just have to be
A - Determined to do the work.
B - Be strategic about the work you’re doing.
Stay Strong,
Geoff Neupert.