Men’s Health Coach · Bali · Root-Cause Performance & Identity
Stop Managing
Symptoms.
Fix the Root.
Men’s health coaching at the intersection of hormones, liver, peptides, gut health, nervous system, and identity. For men done accepting a diminished version of themselves.
“You’re the medicine. We just need to find what’s blocking the dose.”
Coaching Experience
Analysed
Delivery Time
with PrimalScan
Root Cause. Always.
Your body isn’t broken.
It’s responding exactly as it should — to the wrong inputs.
Most men spend years treating symptoms while the root driver — a hormonal cascade, a gut barrier breakdown, an overloaded HPA axis, a methylation defect — goes unaddressed.
I work across the full systems picture. Testosterone, cortisol, thyroid, gut health, liver, nervous system, mitochondria, identity. Because none of it works in isolation.
My full story →Hormones
Testosterone, cortisol, thyroid, insulin — root cause, not suppression
Gut & Liver
Elimination, detox, nutrient absorption, microbiome
Peptides
Pharmaceutical-grade protocols, stacking, bloodwork correlation
Nervous System
HPA axis, allostatic load, stress physiology, identity rewiring
Epigenetics
What’s switching your genes on — or shutting them down
Performance
Body composition, PMM biomechanics, Fascia, Recovery, Hypertrophy, Strength
Coaching Programs
Where Do You Want to Start?
Free Entry Point
PrimalScan
12-system screening + personal recorded review from me. Your root-cause map. Free, within 48 hours.
Start Free →App Coaching · In-App Chat Directly to Me · 24-Hour Daily Reply
The Primal Protocol
Your full personalised health blueprint. Hormones, gut, training, nutrition, lifestyle — built from your scan and biology.
View Program →Rising King
Deep 1:1 mentorship. Biochemistry, nervous system, identity. The full rebuild. Currently full — join the priority waitlist.
Join Waitlist →Primal Wisdom
Deep Education. No Filler.
Hormones
Your Testosterone Lab Results Are Lying to You
Why “normal” range is the wrong target. What Free T, SHBG, and oestrogen are really telling you.
Stress & Recovery
The Cortisol Crash: How Stress Is Silently Destroying You
HPA axis dysfunction, allostatic load, and why working harder makes everything worse.
Gut & Digestion
Your Gut Is Running Your Life
The gut-liver-hormone connection most men miss when energy, libido, and body composition stall.
Peptides & Longevity
Aging Is Optional: The Peptide Protocols That Changed My Biology
15+ years of peptide and coaching evolution. Underground to pharmaceutical-grade. My actual stack explained.
Fat Loss & Metabolism
Why Your Body Refuses to Lose Fat
Insulin resistance, visceral fat biology, and the fat-hormone feedback loop most men never hear about.
Recovery & Performance
Why You Never Fully Recover
GH axis decline, sleep architecture, and why the recovery ceiling is not just overtraining.
Koen Castelein
PrimalFitDad · Men’s health coach · Bali
The Story
I built armour for a decade. Then I walked through an ego death.
Over a decade of competitive bodybuilding. I built the body, the protocols, the results. I also built the armour — using all of it to hide from the parts of me I hadn’t dealt with.
What came out the other side wasn’t the performance. It was the real Koen — and a far more effective understanding of what it actually takes to rebuild a man.
Read the full story →