I just responded to 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 read more using kettlebells? How would I feel improvement in my muscle mass and strength?
“Will KB workouts alone be adequate to develop 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 develop strength, but muscle will be more difficult . The current recommendation for increasing muscle is 1.6g/kg of bodyweight. How would you perceive improvement? You wouldn't. You'd track it through your training log, a tape measure, and body composition measurements.
Yes. Resistance increases muscle and strength, regardless of the device. 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 consider the fact that there are many different reasons 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 critical 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, 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 modest 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 encourage hypertrophy, although the exact metabolites involved are not well characterized (Wackerhage et al., 2019; Schoenfeld, 2010).
Third, the kettlebell, compared to 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 rotates inside your palm and around your hand, landing on the back of your wrist…
And that makes 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,” creates muscle growth.
Plus, the fact that you can move the kettlebell through your legs and quickly extend the muscles of your posterior chain (called “fast eccentrics”) and compress your abdominal musculature making it challenging to breathe…
Also gets a few more of those “hypertrophy mechanisms” depending on how you program your workouts.
Which actually leads us to “how to program your kettlebell workouts for muscle growth.”
I’ve realized there are a few straightforward, but effective 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 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 - Prepared to do the work.
B - Be thoughtful about the work you’re doing.
Stay Strong,
Geoff Neupert.