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 develop muscle mass and boost my strength using kettlebells? How would I feel improvement in my muscle mass and strength?
“Will KB workouts alone be adequate 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 build strength, but muscle will be tougher. The current recommendation for increasing muscle is 1.6g/kg of bodyweight. How would you feel improvement? You wouldn't. You'd quantify it through your training log, get more info a tape measure, and body composition measurements.
Yes. Resistance builds muscle and strength, regardless of the device. The key is knowing how to design 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 deal with 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 key 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 rise in ribosome production improves the muscle's ability to produce proteins, supporting hypertrophy (Roberts et al., 2023; Bamman, Roberts and Adams, 2018).
Hormonal and Growth Factor Influence: While systemic hormones like growth hormone and testosterone have minimal direct impact post-exercise, local growth factors such as IGF-1 affect 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 promote hypertrophy, although the exact metabolites involved are not well characterized (Wackerhage et al., 2019; Schoenfeld, 2010).
Third, the kettlebell, in contrast to 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 rotates inside your palm and around your hand, landing on the back of your wrist…
And that makes 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,” induces 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 challenging 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 found there are 3 simple , but effective ways:
1- Program off a 5RM using the double 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 challenging to build muscle using kettlebells. You just have to be
A - Determined to do the work.
B - Be smart about the work you’re doing.
Stay Strong,
Geoff Neupert.