The Illusion of Muscle Growth

In a 2014 study by Maeo et al titled Neuromuscular Adaptations Following 12 Week Maximal Voluntary Co-Contraction Training, subjects stood with their arm fixed at a 90 degree angle and performed a maximum voluntary isometric contraction for 4 seconds followed by 4 seconds of relaxation. This was considered one repetition. One set was 10 repetitions. They performed five sets per day (50 repetitions), three days per week for 12 weeks. Both muscle strength and size increased significantly in the training group with no change in the control group.

So there you go. If you want to increase muscle size you can do so with isometric exercise. All you need to do is increase the volume of your contractions (the same thing you do when you lift and lower weights). And with measured isometrics you get the bonus of being able to measure your force output for each and every one of those contractions.

But there was another very interesting thing about this study that needs to be discussed: The increase in muscle size did not contribute to the increase in muscle strength.

This isn't surprising. There has never been any evidence that muscle growth and muscle strength are related. The story that exercise-induced changes in muscle size lead to improved muscle strength is a legend. It is folklore. Furthermore, "building muscle" is an illusion, and it certainly doesn't matter.

Stay with me while I explain.

1n 1955, The Problem of Muscle Hypertrophy: A Review  by PJ Rasch was published in The Journal of American Osteopathic Association. This paper examined the lack of direct evidence that muscle hypertrophy from exercise plays an important role in increasing strength.

In 2016, Buckner et al had the benefit of examining an additional 60 years of evidence in The Problem of Muscle Hypertrophy: Revisited. Certainly an additional 60 years of technological advancement combined with a greatly expanded knowledge base would yield more answers, right? Nope. Nothing has changed.

We still have no answers to explain why:

1. Changes in muscle size do not contribute to changes in muscle strength. 

2. Muscle growth gained is lost quickly when workouts stop, yet muscle strength gained persists above baseline for months/years. In fact, it has been demonstrated experimentally that doing a 1 repetition maximum (1RM) test once a month maintains 1RM strength, despite a complete loss of muscle hypertrophy.

3. Muscle growth is the same for low-load or high-load training, yet muscle strength is wildly divergent. High loads produce much greater strength improvement than lower loads.

Yet, here we are 65 years later, in the year 2020, and we continue to believe that changes in muscle strength are contingent upon changes in muscle size, and evaluate the effectiveness of resistance training devices and programs on whether or not they "build muscle."

It's all fiction.

So how did we get here?  

In a 2019 review titled Exercise-Induced Changes in Muscle Size Do Not Contribute to Exercise-Induced Changes in Muscle Strength, Loenneke et al concisely outlined the historical context of how we arrived at the traditional narrative. They present strong evidence that muscle growth is not necessary, sufficient, or contributory for changes in muscle strength. The two seem to be separate and unrelated adaptations to resistance training.

Now let's talk about another misconception: muscle growth.

If a change in the size of your muscles as a result of exercise does not make you stronger, and the relatively quick loss of that increase in size does not make you weaker, and you can get the same change in size if you use a low or high amount of your maximum effort, what is this change and what is the benefit?  

There is no benefit.

In the 1963 textbook Physiology of Exercise, Morehouse and Miller  wrote "It has not been proved that hypertrophy is necessarily a desirable reaction ... it may be simply a by-product of training, perhaps a noxious one." 

Perhaps noxious? Well, considering the various injuries that typically occur as a result of resistance training it can certainly be argued that it is harmful. It's also no secret that multiple markers for tissue damage and skeletal muscle necrosis are significantly elevated after resistance training. 

Is this really a good thing to do on a regular basis?

Is it natural to frequently expend extra energy to move weight through your most inefficient joint angles to achieve a point of discomfort that leaves you inflamed, weakened, stiff, and sore just to temporarily increase the size of your muscles? For no gain? 

Doesn't make sense. 

Here's the truth: Your muscles are perfectly capable of propelling you through life just the way they are. Your nervous system adjusts to yield more strength when you need it and improves its efficiency to handle future demands deep into the future. No change in muscle size is required. The fact that exercise-induced muscle hypertrophy goes away quickly after a few days makes it perfectly obvious that this is not a necessary or even desirable state to achieve. 

Remember, based on all the evidence since the beginning of time, exercise-induced strength gains persist despite a complete loss of exercise-induced hypertrophy gains. Are you seeing the theme here? 

Muscle size doesn't matter. Muscle strength does.

So what is exercise-induced muscle hypertrophy?

It is a by-product; a temporary shift in fluid and blood flow specific to the muscle trained. You may know it as "the pump." It is similar to the increase in size your ankle displays when you sprain it. It is an injury. 

How do you treat an injury? Rest and ice.

In a 2019 study titled Cold Water Immersion Attenuates Anabolic Signaling and Skeletal Muscle Fiber Hypertrophy But Not Strength Gain Following Whole Body Resistance Training, Jackson et al found that muscle hypertrophy was reduced in a group immersed in cold water after each resistance training session compared to a group that passively recovered. Strength was not reduced in either group. 

So a total body "ice pack" reduced hypertrophy? No, it reduced swelling which is typically called hypertrophy.

In a 2015 study by Roberts et al titled Post-Exercise Cold Water Immersion Attenuates Acute Anabolic Signaling and Long-Term Adaptations in Muscle to Strength Training, after 12 weeks of resistance training two days per week, muscle mass accretion was significantly smaller while total fiber cross sectional area and myonuclei density per fiber did not improve significantly in the cold water immersion group (COLD) compared to the active recovery group (ACT). Maximum leg press strength significantly improved in both groups. 

Wait a minute. If the increase in muscle hypertrophy is not just swelling, then why would the COLD group see no significant improvement in fiber cross sectional area and myonuclei density while the ACT group did and they both used the same training program?  

If hypertrophy is real a little cold water shouldn't stop it from happening.

But it isn't. It's an illusion.

Here's the deal. Mother Nature favors power; she likes the greatest strength improvement for the least amount of change in body mass. It's smart economics.

What matters most is what you can do with your body when you want to, or need to. The size of your muscles doesn't propel you out of bed in the morning. The strength of your muscles does.

Focus is on improving the physical capacity and quality of life of the millions of people who want and need the smartest, most efficient and sustainable way to get there. Measured isometric exercise is a perfect fit; it is a great tool for improving neurological efficiency, maximum strength and power to weight ratio.

Strength is all that matters.