Morning Chalk Up Community

How Important is Muscle Mass for CrossFit Performance?

July 20, 2022 by

Form Follows Function

Louis H. Sullivan coined this clever catch phrase not only to demonstrate an excellent example of alliteration, but as a means of articulating an architectural truth.

To sum up the idea behind form follows function: the shape of a structure should primarily relate to its purpose.

I believe we can take this truth and apply it to another structure: the athlete’s physique.

So we could say: the shape of a CrossFit athlete’s body should first and foremost relate to his or her ability to execute the testing body of the Sport of CrossFit.

In other words, if you want to be great at CrossFit you need to look the part.

If you look dramatically different from the average elite CrossFit athlete, you probably don’t have the structure built to allow you to express elite CrossFit performance.

This was the main premise behind: The Ideal Body Type for CrossFit

Performance Paradigm 

It is my observation that most recreationally competitive athletes care just as much about their body composition and overall physique as they do about their game day performance.

I want to be clear that having a physique that is elevated by popular culture or your own mind is not the goal here.  In the words of Kelly Starrett, "It’s about the dirty, nasty, performance."

It’s fine if you want to be shredded and underfat where it inhibits recovery and skews your hormonal profile, but that’s not the conversation we’re having.

So as we look at how the chassis of the human body can aid or hinder an athlete’s ability to perform at their best on the competition floor, try to take your “ideal physique” lens off and put on your performance one.

Hypertrophy Sweet Spot

For each sport, there is a unique sweet spot for hypertrophy.  

The powerlifting community is constantly touting how you need to fill out your frame and move up into your ideal weight class.

Likewise, the cycling community is talking about getting down to your ideal race weight to maximize power to bodyweight ratio.

Each camp is asking, “How much muscle mass do I need to carry on my frame for me to perform at my best?”

CrossFit, no different from any other sport, has an appropriate zone for hypertrophy.

The Double Edge Sword of Hypertrophy

Significant hypertrophy is needed to be an elite CrossFit athlete.

This is undeniable. Just look at the meat sticks lined up on the competition floor at the Games.


Chasing hypertrophy for an already well muscled athlete will often make them worse at the Sport of Fitness.

If you find yourself bulking at that statement, you’re probably in the majority of readers who are constantly working to get stronger to compete at your best in CrossFit.

However, just like the average person coming into competitive CrossFit needs to put on muscle mass, there is a demographic of athlete who has too much.

Benefits of Hypertrophy

More muscle mass means…

…increased potential for maximal strength

…improved Battery & Strength Endurance

…improved ability to move external loads
(weightlifting movements & erg-based cyclical)

Drawbacks of Hypertrophy

More muscle mass means…

…increased output needed for bodyweight movements
(gymnastics movements & locomotion-based cyclical)

…increased demand on cardiac and respiratory systems

…increased oxygen consumption due to more contractile tissue

…more weight and tear on joints (due to increased bodyweight)

I get much deeper in these benefits and drawbacks on this podcast episode.

How To Think About Hypertrophy

With hypertrophy -as with all things- let the goal be the goal.

Don’t chase more hypertrophy unless you are clearly “out of bounds” from the average CrossFit athlete you compete against.

Think about manipulating your body as needed to be able to compete at your best. 

If you are a 5’11” male and 225 pounds, you probably would be best served to dial in the nutrition and lose a few pounds, to help with gymnastics movements and endurance-biased events.

If you are a 5’5” female and 112 pounds, you can certainly gain 20+lbs over the course of training hard for a year or two and it will likely help bring your one rep maxes into a competitive range.

This is an idea I talked about in depth in Optimizing Your Body For Fitness Performance

Next Steps

As a coach, I like to think about hypertrophy as a necessary item to check off, before one of my athlete’s can best express their potential in CrossFit.

Step #1: Get Bodyweight & Body Fat into the Right Range.

• weight manipulation occurs in the off-season

• programming choices should reflect alignment with weight loss / muscle gain interim goals

*weight loss: increased time on cyclical modalities, more bodyweight-biased metcons

*muscle gain: more strength and strength endurance development, more accessory work

Step #2: Eat to Fuel & Train Hard.

• "maintenance" diet to preserve muscle mass and replenish energy stores

• work your weaknesses to overcome your specific limiters

• practice the sport and get mentally ready to compete

Get the Newsletter

For a daily digest of all things CrossFit. Community, Competitions, Athletes, Tips, Recipes, Deals and more.

"*" indicates required fields

This field is for validation purposes and should be left unchanged.