Somewhere between the bottom of my triple espresso and the third set of 30-second Wingates, my lungs started doing their best Bill Lumbergh impression. "I'm gonna need you to go ahead and breathe less terribly on Saturday."

That's when it hit me that I've been watching something deeply strange happen in fitness coaching for the last two decades….

The programming knowledge, the research literacy, the content quality, the nutritional sophistication — genuinely excellent compared to what existed when I started over 2 decades ago.

The average smart coach in 2026 has access to tools and data that would have made exercise scientists in the 90s weep in their protein shake.

And yet…

...A certain class of client stays broken.

Not obviously broken, but subtly broken in a way that doesn't respond to better programming.

Recovery that's inconsistent in ways that make no sense.

Performance that stalls despite doing everything right.

HRV that looks like it was produced by squirrel snorting pre-workout before the first snowfall (1).

Athletes who have good labs, decent sleep, adequate protein, and still can't hold power output in the back half of a hard session.

The coaching response — the completely reasonable, professionally defensible coaching response — is to “optimize harder, Bro.”

Tighten the macros.

Adjust the periodization.

Add more Zone 2 (cough, cough)

Get a another wearable.

Run bloodwork again, but this time the newest and most expensive tests.

And then….drum roll please…….they get the same lack luster results.

Why?

Because the problem was not the program.

The problem was the layer underneath every program that once you see you can no longer unseen. It is the four physiologic systems your body is spending enormous metabolic energy to protect, that most coaches have never programmed for, never deliberately trained, and in some cases never even considered as trainable variables.

They are 1) temperature regulation 2) pH tolerance 3) fuels beyond fat and carbs ala ketones and lactate 4) breathing regulation via O2 and CO2.

Here is an example.

Your blood pH is sitting between 7.34 and 7.45 right now and if you go far outside of that range, you are dead.

Dead, dead, dead.

But, your body is super smart so it will do everything it can to prevent that from happening.

Also keep in mind that the scale is logarithmic — each unit ten times more acidic or alkaline than the last. Mortality at a pH of 7.55 is about 45%. At pH 7.65 it hits 80%.

Eeeek.

Your body is aware of this and it will start to cap and ultimately even shut down performance well before those end points.

If you have never trained these systems deliberately, never pushed pH toward acid with genuine super high-intensity training (SHIT training), never used heat or cold as a calculated stressor, never worked the CO2 side of your breathing equation…

…you have left the high leverage training variables in the human body sitting completely untouched while you argue about optimal protein distribution.

And yes by all means the main 3 areas are the starting point of exercise, nutrition and sleep; but once you are getting a B in those, where do you go next?

That is what the Physiologic Flexibility Certification is designed to address.

And once you address them you unlock the next level of performance, all while making your body much more resilient in the process.

I am stoked to announce that the Phys Flex Cert is open now!

​https://miket.me/physflex <--full details

This week I'm going deep on each pillar — real mechanism, what breaks when it's stiff, what to do about it.

Much love and metabolic mayhem,

Dr. Mike

PS - Enroll by this Wed at midnight PST and get a free 1-hour private consulting call with me. $250 value, yours at no cost if you're a fast mover.

PPS -Here is what Matt had to say

"I was telling some of the guys that you literally not only came to the conclusion of the importance of these systems as a whole, but also that we should be trying to optimize their function for health and performance before anyone in the Ex Phys was onto this.

Not a single person has suggested that we approach training/optimizing them in any way.

Now everyone is coming to understand that this parameter is what is separating the elite." — Matthew DesRoches

​https://miket.me/physflex <--full details

Reference

1) I have this strange obsession to get an HRV measurement on a squirrel as they constantly look like they are sympathetic 24 /7 and their HRV must be in the single digits. So far only 3 studies and they all looked at the little buggers during torpor (hibernation) and not searching of nutZ!

Zanetti, F., Chen, C.-Y., Baker, H. A., Sugiura, M. H., Drew, K. L., & Barati, Z. (2023). Cardiac rhythms and variation in hibernating Arctic ground squirrels. Physiological and Biochemical Zoology, 96(3), 167–176.

Russell, R. L., O’Neill, P. H., Epperson, L. E., & Martin, S. L. (2010). Extensive use of torpor in 13-lined ground squirrels in the fall prior to cold exposure. Journal of Comparative Physiology B, 180(8), 1165–1172.

MacCannell, A. D. V., Jackson, E. C., Mathers, K. E., & Staples, J. F. (2018). An improved method for detecting torpor entrance and arousal in a mammalian hibernator using heart rate data. Journal of Experimental Biology, 221(4), Article jeb174508

_____________________

Mike T Nelson CISSN, CSCS, MSME, PhD
Associate Professor, Carrick Institute
Owner, Extreme Human Performance, LLC
Editorial Board Member, STRONG Fitness Mag

Mike T Nelson is a PhD and not a physician or registered dietitian. The contents of this email should not be taken as medical advice. It is not intended to diagnose, treat, cure, or prevent any health problem - nor is it intended to replace the advice of a physician. Always consult your physician or qualified health professional on any matters regarding your health.

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