Can’t I Just Lift Weights Faster for Cardio?


Hola from the frozen hellscape of Minnesota, where I’ve been rudely ejected from the warm embrace of Mexico and thrown straight into a climate that wants me dead.

I dragged my jet-lagged carcass out of bed, threw on layers like I was suiting up for a deep-space mission, and hit my AM run anyway—because I am not a coward. haha

Then I punished myself further with some rower sprints, just to remind my body who’s in charge this AM too.

Speaking of pain, let’s talk about one of the dumbest fitness myths that refuses to die....

...before I give you the low down there, a quick reminder:

Flexible Meathead Cardio Kicks Off This Tuesday, March 4—Are You In?

If you’re already enrolled, check your inbox for the survey on the best session times. If you haven’t filled it out yet, do it now—I’m locking in the final times tonight.

And don’t worry, everything will be recorded, and you’ll have lifetime access to all the material, including future updates.

But for now, let’s talk about the MetCon cult’s favorite excuse for avoiding real cardio.

"Can’t I just lift weights faster? My heart rate goes up, so it must be cardio, right?"

In short, no Brosefus.

No, it is not.

This is the same logic that says, “I drank six vodka sodas, therefore I am hydrated.”

Just because something sounds logical doesn’t mean it’s physio-logical (shoutout to Dr. Peter Lemon on that quote).

Why Lifting Faster Does Not Replace Cardio

Let’s break this down before you hyperventilate mid-set and pretend it’s aerobic adaptation.

What Happens to Your Heart When You Lift?

Picture this: You’re under a loaded barbell, grinding out 12 soul-crushing reps of squats. By rep 8, your vision is going dark, your ancestors are calling you home, and somewhere deep in your nervous system, your brain is screaming for blood.

Your heart is freaking out.

  • Its only job? Keep you alive.
  • It does this in two steps:
    1. Fill up with oxygen-rich blood (preload).
    2. Pump that blood out before you collapse under a pile of iron.

Sounds simple, right?

But here’s where lifting screws everything up.

  • Your muscles are squeezing the life out of your blood vessels.
  • Less blood gets back to your heart.
  • Your heart has to fight like hell to pump against massive resistance (aka afterload).

And over time, your heart adapts—but not in a beneficial way.

The Dark Side of Lifting Without Cardio

When your biceps get bigger, that’s awesome.

When your heart walls get bigger, that’s a ticking time bomb.

Over time, your cardiac chamber size shrinks, meaning less blood per beat, higher stress, and a heart that functions more like a brick than a pump.

And in the extreme cases?

  • Left ventricular hypertrophy (which sounds cool until it kills you).
  • Scar tissue in your heart (not as fun as muscle gains).
  • Electrical conduction issues (aka, your heart fires like a misfiring spark plug).

This won’t happen overnight, but give it a decade of nothing but lifting and zero cardio, and you’ll become that guy who gasses out walking up a flight of stairs while a 60-year-old endurance athlete breezes past you.

Is that what you want?

To be a swollen meat-sack with the endurance of a drowning sloth?

What Happens When You Do Actual Cardio?

Now, let’s look at what happens when you do real aerobic work instead of pretending that your high-rep thrusters are some kind of magical cardio substitute.

  • More blood returns to the heart (higher preload).
  • The heart expands (diastolic filling / stretching).
  • Blood moves easily (lower afterload).

Translation?

Your heart turns into a high-performance endurance engine, capable of powering longer workouts, better recovery, and heavier lifts.

And before you panic—no, I am not telling you to turn into a waif-like marathoner who collapses in a stiff breeze.

What you want is balance—a heart that can keep up with your training, fuel your muscles, and let you smash weights without feeling like you just sprinted up Everest.

The Solution: Train Your Heart Like You Train Your Muscles

Neither extreme is ideal.

You don’t need to run 20 miles a week, but you do need dedicated aerobic work if you want to keep lifting heavy for decades.

  • I am not telling you to stop lifting.
  • I am telling the METCON crews out there to stop pretending that “lifting faster” counts as cardio.

This is exactly what I teach in Flexible Meathead Cardio.

  • How to add cardio without murdering your gainZ.
  • Training templates designed for lifters, not endurance weirdos.
  • The best protocols to build both strength and endurance without turning into a noodle-armed cardio bunny.

If you still think you can just lift weights faster and call it cardio, your heart is laughing at you.

There is nothing wrong with doing METCONS and we do deep down that rabbit hole in the Level 2 course;..

...but it is not an aerobic adaptation and is its own adaptation; thus doing only METCONS will not build your true aerobic base.

Enrollment closes March 3 at midnight PST. We start March 4.

https://miket.me/cardio

Much love, cardiac horsepower, and an engine that actually works,
Dr. Mike

PS - we will briefly cover some movement methods in the course to make sure you are not creating injuries when you are doing your aerobic work. Here is what Neil - who was on Team HeartStrong that placed third in the big Race Across America - yes, biking from San Diego to Atlantic City in 7 days in 2007 had to say:

"Mike is like a miracle worker. One time I was walking with him and he asked me if I had ever been in an accident. I said no. Then he said, You walk funny. He had me do just a few odd exercises and suddenly my whole gait felt different. It actually felt smooth. I didn’t know it could feel like that. That whole episode lasted about 5 minutes. Unbelievable!"
–Neil Erdmans, Team Strong Heart Race Across America (RAAM) Rider
Team Heartstrong finished 3rd in the 2007 RAAM

More info and enrollment at

https://miket.me/cardio

_____________________

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.

..

Dr Mike T Nelson

Creator of the Flex Diet Cert & Phys Flex Cert, CSCS, CISSN, Assoc Professor, kiteboarder, lifter of odd objects, metal music lover. >>>>Sign up to my daily FREE Fitness Insider newsletter below

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