Why Millennial Workouts Stop Working in Perimenopause (And What to Do Instead)
Millennial fitness culture taught us one thing:
Push harder.
Tae Bo in the living room.
Jillian Michaels yelling through the 30 Day Shred.
Pinterest quotes about “beast mode.”
Two-a-days if you were serious.
More cardio.
Eat less.
Sweat until you feel accomplished.
And for a while… it worked.
Until it didn’t.
Now many of us are in our late 30s and 40s wondering:
When did what used to work stop working?
Why does pushing harder make me feel worse now?
Why am I injured… again?
This isn’t a discipline problem.
It’s biology.
I recently sat down with Dr. JJ Thomas, a Doctor of Physical Therapy with over 24 years of experience. She helped me unpack what’s actually happening inside our bodies in perimenopause and why the insane PUSH HARDER strategy is backfiring.
If you’ve felt like your body is changing (even though you’re doing what you’ve always done), keep reading.
The Real Shift Happening in Your 30s and 40s
One of the biggest changes happening under the surface is something called anabolic resistance.
Here’s what that means:
As we age, our bodies don’t build and maintain muscle as easily as they used to.
In your 20s, you could:
Lift moderate weights
Eat whatever protein happened to be around
Recover quickly
In your 40s?
Your body requires a stronger signal to build muscle.
And it loses muscle more easily.
That matters because muscle isn’t just about looking toned.
Muscle regulates:
Blood sugar
Metabolism
Hormones
Energy
Long-term longevity
This is why “just do more cardio” stops working.
Why More Cardio Can Backfire in Perimenopause
When we gain weight or feel uncomfortable in our bodies, our millennial instinct is:
“I’ll just work harder.”
More spin classes.
More HIIT.
More Orange Theory.
But here’s the problem:
If your body is already in a stressed, hormonally shifting state, piling on high-intensity cardio can:
Increase cortisol
Increase inflammation
Break down tissue
Prevent muscle growth
Make recovery harder
And if you’re not building muscle… your metabolism doesn’t get what it needs to do it’s thing.
This is where so many women get stuck:
Working harder.
Eating less.
Feeling worse.
Why Protein Matters More Than Ever
Yes, I know, I know. You’ve heard it a million times.
“Eat more protein.”
But here’s why it actually matters in this stage of life.
Your body is constantly repairing and replenishing tissue. Every day, hundreds of billions of cells turn over.
If you don’t have enough amino acids (the building blocks of protein), your body literally cannot rebuild muscle, tendon, or connective tissue effectively.
Dr. JJ gave this analogy that I love:
Imagine your kid walks into a room to build a Lego house.
In one corner: a tiny pile of Legos with barely any variety.
In the other: a massive pile with colors, shapes, and options.
Which pile builds a stronger house?
Protein is your Lego pile.
If it’s too small, your body breaks down faster than it rebuilds.
Train Patterns, Not Just Muscles
This might be the biggest mindset shift of all.
For years, we were taught to train muscle groups:
Leg day.
Arm day.
Abs.
But your body wasn’t designed to function in isolated parts.
It was designed to move in patterns.
Think:
Rotation
Anti-rotation
Pushing
Pulling
Squatting
Hinging
Twisting
Climbing
Carrying
When we train movement patterns instead of just muscles, we build:
Structural resilience
Better posture
Fewer injuries
Greater functional strength
This is what changed everything for me.
After multiple herniated discs, I realized I didn’t just need to “get stronger.”
I needed to get stronger in a smarter way.
And when I shifted toward pattern-based strength training, something surprising happened:
I stopped obsessing over aesthetics…
And my body changed anyway.
Looks vs. Function: A Necessary Reframe
In our 20s, “being in shape” meant thin.
But Dr. JJ has a great re-frame for you.
Being “in shape” should mean, changing the way your body is shaped. In other words…
Structural integrity
Strong posture
Resilient joints
Functional movement
This is the best part. When you train for function, the aesthetics often follow.
In other words, when you’re just trying to get this late 30s/40-year old body to work for you, you actually get more toned and — for lack of a better word — hotter while you do it.
But the motivation shifts.
Instead of:
“I want to shrink.”
It becomes:
“I want this body to last.”
Damn. That’s powerful.
What Should You Actually Do?
If you’re overwhelmed, here’s a simple starting framework:
Prioritize strength training 2–3 times per week
Ensure adequate daily protein intake
Incorporate some mobility work
Vary your stressors (don’t do the exact same workout daily)
Stop defaulting to “more cardio” as your only strategy
You don’t need to overhaul everything overnight.
But you do need to stop applying a 25-year-old strategy to a 40-year-old body.
The Most Important Takeaway
Dr. JJ said something that stuck with me:
Taking care of your fitness is not selfish.
It increases your capacity.
When you build strength:
You regulate hormones
You improve energy
You reduce injury risk
You increase longevity
You show up stronger for the people you love
This isn’t about six-packs.
It’s about building a body that works for you in the second half of your life.
Want to Learn More?
You can follow Dr. JJ Thomas on Instagram at:
@drjjphysicaltherapist
And you can listen to our full conversation on The Next Phase Podcast here:
#21: Why Millennial Workouts Are Backfiring in Perimenopause (With Dr. JJ Thomas, DPT)
If this hit you. Like, you’re nodding your head thinking this makes sense… share it with a friend who still thinks the answer is just more cardio.
We deserve better information.
And stronger bodies.
Much Love,
Stacey
p.s. I know this stuff can be overwhelming. So I created something to help that you can stick to your refrigerator for easy access.
My free Cycle-Syncing Food, Fitness & Energy Guide walks you through how to align your workouts, nutrition, and expectations with your hormonal phases instead of fighting them.
You can download it here → Cycle Syncing Map