Hypertrophy Simplified: Build Muscle Smarter, Not Harder
Everyone wants to build more muscle (without getting bulky, I know) but there is A LOT of information on it within the fitness industry, and the deeper you go the more confusing it can get. So, over the next few weeks, I want to try to filter out the rubbish and give you some information that will help you understand things a bit better and, more importantly, help you apply that information to your training.
This is going to start a little nerdy but hang in there..it all comes together and it's extremely important as we hit 2025 hard.
What is Hypertrophy?
Hypertrophy is the increase in the length and cross-sectional area of muscle fibers, or the increase in muscle mass or volume at the whole muscle level. If you want to be jacked you want Hypertrophy to occur.
The 3 Mechanisms of Hypertrophy
You might have heard that there are 3 main mechanisms of Hypertrophy:
1 Mechanical Tension
2 Muscle Damage
3 Metabolic Stress
Mechanical Tension is the tension on each muscle fibre produced by force generation (active mechanical tension) and stretch (passive mechanical tension)
Muscle Damage is damage caused to a muscle after training (Exercise Induced Muscle Damage)
Metabolic Stress is the accumulation of metabolites such as lactate in muscle cells
Without brushing over Muscle Damage and Metabolic Stress completely, we have a clear model of how mechanical tension can produce muscle growth. However, it is very hard for us to test if muscle damage and metabolic stress produce growth on their own as mechanisms of Hypertrophy because we can’t test Muscle Damage and Metabolic Stress without there being some Mechanical Tension present. So, for now, we are just going to focus on how to create Mechanical Tension.
How to Create Mechanical Tension
To place mechanical tension on a muscle fiber, two key factors are required:
High motor unit recruitment
Involuntary slowing down of the lifting phase
*The above is related to Active Mechanical Tension. There is something called Passive Mechanical Tension, which happens through stretch but Active Mechanical Tension is where the long-term gains are at!*
Inside our muscle cells, we have motor units, and attached to those motor units are muscle fibers. For a muscle fiber to experience Mechanical Tension, it has to first be active, and we activate more motor units by having a high degree of effort (high resistance through load/bands etc).
Along with this high motor unit recruitment we need the lifting or concentric portion of the movement to slow down involuntarily because our effort level is high.
Practical Tips for Your Training
Choose exercises that allow you to go heavy or use high resistance, as this will create high motor unit recruitment. Then, make sure your last few reps start to slow down involuntarily because your effort levels have had to increase. Ideally, you want to stay around the 5-8 rep range which I know sounds low but I will cover that in another newsletter. You want to be working close to or to task failure (you can’t do another rep).
If you’re hitting 8 reps and you feel like you could do loads more then go heavier or increase the resistance…..simple.
These slow, challenging reps are called stimulating reps and these are the ones that matter for building muscle. So, if you want to get the most out of your training to get HUGE, lift heavy weights and make sure those last few reps really start to slow down.
The Takeaway
If you want to maximize hypertrophy, focus on creating mechanical tension through:
Heavy resistance to activate motor units.
Controlled, slow reps that naturally slow down at the end of a set.
Working close to failure to recruit those all-important stimulating reps.
Building muscle doesn’t have to be complicated, but it does require effort and intensity. Lift heavy, challenge yourself, and let those slow, final reps do the work.
