Limitations of Systems
CrossFit is concurrent training.
You are getting pulled in multiple directions as an athlete because you are training for many adaptations.
It’s less about an “interference effect” and more about limitations on systems.
The more polarized the adaptations you seek are relative to a particular system the harder it will be to hold both concurrently.
You can’t be an elite marathon and strongman at the same time.
Not because inherently you can’t train and get adaptations in both, but because of the limits on a system, in this case hypertrophy.
You can choose to hold as much muscle mass as you want, but if you have a ton you won’t be able to be a great runner, and if you don’t have enough you won’t be a great strongman.
An example of another system is muscle fiber type.
Fibers can be fast twitch, which means they can rapidly generate a lot of tension, yet they fatigue quicker.
Or they can be slow twitch, which means they have excellent contractile repeatability, but they can’t produce high forces.
And yes, there are hybrid fibers with qualities of both, but generally the more experienced a trainee is, the more polarized their fiber types become.
In theory, if you have 100 muscle fibers, you can have 70/30 or 60/40 slow twitch, or you could have 85/15 fast twitch, but it’s impossible to go over 100%.
The point of this example is to illustrate how constraints on a particular system will impose limits on how strong or enduring someone can get at the same time.
Now, you can add muscle fibers and hypertrophy the muscle, but also comes at a cost to endurance performance. You weigh more, there’s a higher oxygen delivery demand if you have more muscle mass, etc.
My point is there are lots of self-limiting systems like this in the body: nervous system tuning, hormonal profile, bodyweight, bodyfat, lean body mass, cardiac development, metabolism substrate use, etc.
Many of these I’ve talked about before…
Related Resources
• Developing Strength & The Aerobic System Together
• Optimizing Your Body for Fitness Performance [Ep.012]
• The Benefits & Costs of Hypertrophy [Ep.047]
• How Temperature, Thermoregulation, Heat & Cold Impact Performance [Ep.059]
Tension Management: The Linchpin of Performance
However, there is one more concept that is critically important to concurrent training like we see in CrossFit: Tension Management.
Tension isn’t a singular system, like fiber type or nervous system state, but rather it impacts and is impacted by many different systems.
I’ve found an understanding of how to regulate and manipulate tension to be one of the linchpins to unlocking higher levels of performance in concurrent training.
Why?
Because focusing on fiber type or cardiac development has zero utility to an athlete.
They need to focus on the one thing that matters: being in a physiological & psychological ready state for their next session.
“Execution is worshiped.”
Brian St. Andrews
As a coach, I don’t want my athletes to focus or worry about physiology or program design.
That’s my job as their coach.
Focusing on manipulating tension is one of the best things an athlete can do because it brings their focus back into their own mind & body and helps prepare them for their next workout.
How to Manipulate Tension
The best way I’ve found to manipulate tension is through mental framing and self-talk.
When you are preparing for activities that require high forces, rigidity and stiffness to be successful, the athlete needs to have tools to conjure up intensity.
On the other hand, if the athlete is preparing for endurance activities they need to practice patience and fluidity, resulting in a much more relaxed, sustainable version of power because being smooth, methodical, and fluid is what translates to performance.
CrossFit: Another Layer
CrossFit and similar type mixed modal events (e.g. Spartan races, Hyrox, etc.) it’s not enough to modulate tension and arousal between sessions, you must learn to make intraworkout adjustments.
You have to be able to manipulate tension and arousal moment by moment.
Let’s take an example…
4 Rounds for Time
-400m Run
-4 Deadlifts @ 85%
In order to be successful in this type of environment you have to control your mental framing, output and rigidity to put yourself into the minimal effective level of tension. Any amount too much is wasted energy in such an event.
So as you run your mental space and self talk is “relaxed, efficient, smooth, methodical” until a few seconds before stepping up to the deadlift bar. Then it becomes, “get tight, big breath and hold, drive hard, move fast.”
Manipulating Tension Through State
Lastly, elite athletes regulate their state in the moments after a workout and return to homeostasis faster than their sub-elite peers.
This is due to a few factors including having a more robust aerobic system and having better coping mechanisms for exercise induced pain leading to a dampened stress response from hard bouts of work.
Related: Shift State [Ep.008]