In Part 1 yesterday I started to introduce you to the fact that big muscles don’t always mean the biggest strength. So lets continue this interesting topic here…

The different type of hypertrophy

Nick Winkelman is a nationally recognized Strength and Conditioning Coach who has helped and supported many professional athletes in the NFL, MLB and NBA.


He recently released a video called Functional vs. Non Functional Hypertrophy during a webinar.

He stated that there are two different types of muscle hypertrophy. Muscles are complex structures with many parts that each play a specific role in the force that can be produced through a muscle contraction.

Myofibril and sarcoplasm hypertrophy

Two aspects of this are obviously the myofibrils, and also the sarcoplasm that encases these muscle fibers. Each has hypertrophy, or growth, capabilities, however, only one of them actually increases the force, strength, or speed of the actual muscle contraction, and that is myofibril hypertrophy.

Sarcoplasmic hypertrophy

Sarcoplasmic hypertrophy is the increased amount of fluid, or sarcoplasm, in the muscles, as well as the increased number of non-contractile proteins. This type of hypertrophy alone will not increase the strength of a particular muscle.

Myofribillar hypertrophy

Myofibrillar hypertrophy is the increased size of the actual muscle fibers, which includes all of the aspects that make a muscle contract such as the actin, myosin and other contractile elements. This is the type of hypertrophy that will increase force production and strength.

muscle size and strength_4Muscle size and strength

Each type of hypertrophy is important, as the sarcoplasm is what “gives life” (as Winkelman states) to the muscle, but the problem arises when sarcoplasmic hypertrophy is not accompanied by myofibrillar hypertrophy.

Body builders vs. NFL players

This is the case for bodybuilders. A lot of the time, they have huge muscles, but when compared to a NFL linebacker for instance who may be smaller than them, the bodybuilders actually lift less weight.

How can this be?

Well, each of them uses different hypertrophy training protocols and bodybuilders experience more sarcoplasmic hypertrophy than myofibrillar. The purpose of the NFL needs the players to not only be strong, but bigger as well, while the emphasis for bodybuilders is more on the overall size.

Therefore it really comes down to what your overall original goal is.

So according to Nick Winkelman, depending on the type of hypertrophy training one uses, size once again does not necessarily determine strength, and vice versa.

Motor innervation

Another factor that plays into this issue is neural innervation. During strength training, no one actually uses all of the muscle fibers that are contained in their body.

Throughout adolescent years, the main increase in strength is actually attributed to the body learning how to recruit more motor neurons connected to muscle fibers, not the actual muscles getting bigger.

Using this logic, kids in their early years could be smaller than others, but depending on how they have been active and how well their body has learned to innervate the muscular neurons, could easily be stronger.

muscle size and strength_5In a 1982 issue of the Journal of Physiology, Maughan, Watson, and Weir performed tests on male and female subjects measuring the force produced by the knee extensor muscles and the CSA of those muscles. They found significant positive correlation between the two, but not causation.

All of this may seem very confusing and maybe even unrelated, but let me condense all of the previous information stated in this, and Part 1 of my article into one sentence:

Muscle size and strength are related, but you can in fact have one without the other.

As you are training with weights, even if you train for muscular endurance, a slight increase in size and strength will occur.

You can isolate each of these factors and only train for hypertrophy (size) or strength as well. In doing this though, you will increase the other aspect just because your body adapts to the different stress.

Connect with Expert Jon Kilian.

WatchFit Experts change lives!

And they can do the same for you.


Pollyanna Hale Health and Lifestyle coaches
Lost 13 Kg in Total
Mel, 32y Location: London, United Kingdom Working with Pollyanna changed everything. I lost 13kg, got toned and have more energy than ever! Get same results!


Chriz Zaremba Fitness Consultant
Lost 45 Kg in Total
Chris, 50y Location: London, United Kingdom Lost 45kg after the age of 50 and now competes and wins physique competitions and runs marathons Check our weight loss plans