Lactic acid didn’t do it. Your buffering system got mugged.

There’s a certain kind of coach I’ve met a thousand times.

Good intentions.

Solid heart of 14 karat gold.

Probably owns at least 3 overpriced recovery gadget and still says “lactic acid” like it’s 1997 and we’re all wearing Zubaz pants in a Gold’s Gym parking lot with his gallon of distilled water.

...but then his athletes starts dying halfway through a brutal set of intervals, and they spit out the same line that’s been passed around the fitness world like a haunted hand-me-down:

“Yeah, that lactic acid will get ya.”

This line makes Dr George Brooks pull all of his grey hair out at once.

That’s not what got ya, chief. Stand by as I explain.

The Lactic Acid Myth

That story has had one hell of a run, mostly because it sounds plausible.

Legs burning? Must be acid. And not the kind that makes you stare at a tree until the branches melt and start talking to you.

Breathing like a malfunctioning accordion?

Must be lactic acid again.

Power dropping off a cliff while your athlete makes that thousand-yard stare face like they’ve just seen the tax bill for poor programming?

Yep, they blame lactic acid.

But the whole story is wrong.

Not a little wrong.

Wrong molecule. Wrong mechanism. Wrong solution.

We can debate if lactic acid even exists, but if it does, it immediately turns into lactate plus H ions.

Lactate is not the thug in this back-alley physiology mugging. That is the pesky H ions.

Lactate is useful as hell as an amazing fuel.

Your heart can burn lactate directly for fuel.

Your brain can use it directly and may prefer it after a concussion (ditto for ketone bodies here too).

Your oxidative muscle fibers can grab lactatet and put it to work.

Lactate is less “criminal mastermind” and more exhausted night-shift janitor trying to keep the building running while chaos erupts in three different rooms.

The real problem is those hydrogen ions.

You go hard enough in training — especially with the kind of ugly, soul-shaking work I call SHIT training, which is Super High Intensity Training — and now you’re making mountains of lactate plus H+ ions.

That’s when the wheels get loose.

pH starts dropping.

The muscle environment gets more acidic.

Contractile function turns sloppier than a gas-station chili dog at 2 AM where they legally have to call them "Wizard Fingers" as they are no longer food.

Force output leaks out of the system.

What felt explosive a minute ago now feels like sprinting through wet cement while your lungs threaten legal action.

That’s the limiter.

Not “lactic acid.”

Why It Matters

And this matters because if you misidentify the limiter, you will keep coaching the wrong thing over and over while wondering why your athletes or you keep stalling at the exact same ugly point in training and competition.

Which is what most people do, especially those roaming the purple halls of PF too late at night.

They watch an athlete crumble under repeated hard efforts and call it bad conditioning.

Or weak mindset.

Or lack of grit.

Or some vague BS about “mental toughness.”

I will bet you 2 soggy Wizrad Fingers that your athlete has the buffering capacity of a wet paper bag.

That is not a character issue.

It is a physiology problem due to a piss poor training plan.

Once you understand that H+ accumulation and pH regulation are the real issue, your whole coaching lens changes.

Now you’re not standing there barking “try harder Bro” like a lunatic PE teacher possessed by a spin-class demon cloaked in neon.

Now you’re asking useful questions.

Can this athlete tolerate a rising acid load?

Can they buffer hydrogen ions effectively?

Can they hold output when the internal chemistry starts looking like a meth lab hit by lightning?

Are they able to recover between repeated hard efforts without turning into a shivering bag of day old soup?

That is the pH pillar.

And very few coaches train it deliberately.

Athletes slam into this wall everywhere: in the ugly backend of repeated intervals, in the back half of games, during the moment in a race where pace suddenly turns from confidence to hallucination, or in those hideous hypertrophy sets where the legs are full, the chest is burning, and the soul is already halfway out the emergency exit.

Most coaches see that collapse and slap the wrong label on it.

...But if the real limiter is buffering, then the solution is not more yelling.

It’s better programming.

That’s why this matters.

Because the minute you can tell whether someone is aerobically limited or buffering limited, the whole map changes.

Inside the Phys Flex Cert, I show you exactly how to train this system without cooking the athlete into a twitching puddle of regret fueled by 2 year creatine and gas station pseudo meth tabs.

We cover how to use SHIT training and other interval methods to create the right dose of pH stress.

How to sequence those sessions so you build adaptation instead of just hoarding fatigue like a deranged little cortisol goblin.

How breathing changes blood pH in real time.

Plus how to separate true buffering limitations from aerobic limitations.

We even do a deep dive into which supplements may actually help versus which ones are just expensive glitter in a tub.

Because once you understand this layer, you stop calling everything “conditioning.”

And when you stop mislabeling the problem, your coaching gets sharper fast.

That’s when athletes stop folding the second things get interesting.

That’s when your programming stops looking good on paper and starts producing results when the suffering meter pegs red.

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

Payment plans are live at checkout via Affirm and Klarna.

If you need something else, hit reply.

Remember that the Fast Action Bonus of a 1 hour call with me to ask me anything (a legit $250 value) goes poof at midnight tonight, Wed April 22 at midnight PST.

Much love, lactate, and organic chemistry,
Dr. Mike

PS — “The Phys Flex Cert was the best course I have ever done!.” — Christopher S. Ellis, DPT, Dynamic Physio Therapy

PS — Tomorrow I’m digging into lactate as a fuel and why a whole lot of endurance programming still treats fuel flexibility like a religion instead of a tool.

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

____________________

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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