09 Oct Sarcoplasmic Hypertrophy Vs. Myofibrillar Hypertrophy: What You Need to Know.

The science shows us there are 2 different types of muscle growth or hypertrophy.

And, it’s important to understand this because one type appears to be much more functional than the other type.

I’ll explain what I mean.

This hit me like a ton of bricks when I read this in several great strength training books.

As a matter of fact, one of those books stated that traditional “bodybuilding” hypertrophy does absolutely nothing for performance.

As a former bodybuilder, that was really tough to see in print, but I have to say it’s true.

At least the way I trained as a bodybuilder doing lots of isolation exercises, machines, and high reps and sets.

That’s why I wanted to share this information.

The 2 types of hypertrophy are sarcoplasmic and myofibrillar (also called sarcomere hypertrophy in certain textbooks).

Sarcoplasmic hypertrophy is when the sarcoplasm (the fluid inside the muscle cell) increases it’s volume which makes the muscles larger and fuller.

Unfortunately, science shows us this does virtually nothing for force production, meaning it is not what makes you stronger and does not improve muscular performance.

The sarcoplasm is the fluid in the muscle cell which contains glycogen, minerals, fats, and dissolved proteins, so it’s easy to see how this would not improve function or muscular contraction.

On on the other hand, there is myofibrillar hypertrophy which is an enlargement of the muscle fiber as it gains more actin and myosin proteins, which are the contractile proteins (the myofibril is a rod like unit of muscle which contains these muscle proteins).

The myofibril (and the smaller unit, the sarcomere) is where the muscle contracts, so the more and bigger myofibrils (and sarcomeres) we have, the stronger we become.

This is the type of hypertrophy that leads to increased muscle force production.

I think you would agree that this is a desired outcome, especially for athletes, as compared to sarcomplasmic hypertrophy.

Can we selectively train for myfibrillar hypertrophy over sarcoplasmic?

Although it appears we can’t train for pure myfibrillar hypertrophy, we train to elicit more myofibrillar as compared to sarcoplasmic hypertrophy.

This is very important to know to improve strength and performance.

How to train for myofibrillar hypertrophy.

Here are some specific methods and programming to training for this, from a scientific and common sense approach.

Ways to increase myofibrillar hypertrophy include:

• Olympic weightlifting (explosive strength and power)
• Powerlifting (maximal strength and power)
• Kettlebell training (explosive and maximal strength)
• Appropriate bodyweight training methods
• Effective program design (reps, sets, and intensity)
• Other total body, multi joint compound lifts and strength training methods

These are some of the ways we do this and not with traditional bodybuilding style methods (machines, isolation exercises) and programming (high rep, moderate intensity).

Specifically with programming, lower reps (rep ranges 1-6) and heavier weight will promote myofibrillar hypertrophy whereas higher reps (rep ranges 8-12) with lower intensity will elicit more sarcoplasmic hypertrophy.

The bottom line is to know how to train for strength and performance as opposed to just training for aesthetics, if strength and performance are your goals.

Remember, no matter what you do, you will have both types of hypertrophy, but we can influence one over the other.

Common sense would tell us that more athleticism, strength, power, and functional enhancement will be achieved with weightlifting, powerlifting, and kettlebells as compared to traditional bodybuilding style training.

And, I can speak from personal experience here, as I did traditional bodybuilding style training for many years, which did nothing for me from a performance standpoint compared to the physical capabilities I have today.

This is the truth.

This is also why most top level bodybuilders won’t be winning a strongman, powerlifting, or weightlifting competition any time soon unless they trained for that purpose.

Looking strong (as in having significant hypertrophy) and actually being strong are sometimes very different and distinct things.

This is not taking anything away from bodybuilding (as I used to be a competitor myself), but the methods, goals, and outcomes are very different.

Sarcomplasmic hypertrophy has been termed “non-functional” and if you understand the muscle cell physiology as I’ve explained it, you can see why.

Strength training or resistance exercise will get us stronger and build muscle, but there are different methods and different programs to accomplish these goals.

If hypertrophy is the goal, you can certainly achieve that with a more “functional” training approach, as with the methods mentioned above.

Myofibrillar hypertrophy is functional hypertrophy because we are changing the structural and functional components of the muscle.

Again, we’re going to have a combination of both, as you can’t have pure myofibrillar hypertrophy, but since sarcoplasmic hypertrophy doesn’t help us, from a performance standpoint, does it make sense?

If you want to truly perform better, then understanding this concept will be of great benefit for you.

If you’re competing in bodybuilding, then that type of training could make sense.

But, even some top level bodybuilders, like former Mr. Olympia, Ronnie Coleman, understand this concept.

Ronnie was strong and trained for hypertrophy and performance by doing heavy squats and deadlifts, for example.

He not only had significant hypertrophy, but he was incredibly strong.

And, I think more of today’s bodybuilder’s probably have a better understanding of this concept, as well.

I have to be honest, if I were competing today I would certainly take a more functional strength training approach, based on what I now understand.

The key point is that research has shown that myofibrillar hypertrophy is what contributes significantly more to strength and performance than sarcoplasmic hypertrophy.

With that, if we want to truly improve strength and performance, we need to train the right way.

It’s as simple as that.

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REFERENCES: 

Supertraining by Yuri Verkhoshansky and Mel Siff, 6th Edition.

Facts and Fallacies of Fitness by Mel Siff, 6th Edition.

Functional Hypertrophy: What is it? Why you need it. And how you can achieve it. By Todd Wilson

Scott Iardella writes about strength training methods to optimize health and performance. If you enjoyed this article, join a strong and growing community of passionate fitness enthusiasts and subscribe below.