Results in 6 weeks

Stop guessing. Get UnderForge®

Premium muscle and strength building coaching. Delivered by humans, improved with AI.

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You're not lazy. You're just missing a system.

×Contradictory advice from every source
→
✓One systematic, evidence-based approach
×Personal coaches are too expensive
→
✓Evidence-based guidance at a fraction of the cost
×Eating 'lots of protein' but no real plan
→
✓Optimized nutrition timing for your metabolism
×Starting strong, then losing momentum
→
✓Built-in accountability that keeps you honest

A unique approach for your unique body and goals

STEP 01

We get to know each other

Understand your goals, lifestyle, and what's held you back before.

We get to know each other
STEP 02

Onboard through our app

Designed exclusively to help people gain strength or muscle mass.

Onboard through our app
STEP 03

Follow your personalized plan

Nutrition, training and recovery built around your body and schedule.

Follow your personalized plan
STEP 04

Touchpoints with your coach

Regular check-ins to review your plan, progress, and adjust as needed.

Touchpoints with your coach
Learn more about the app →
Is this for you?

You've probably thought one of these

If any of these sounds familiar, UnderForge was built for exactly that.

"I don't have time for this."

Your plan fits the days and minutes you actually have. Minimal logging, clear weekly targets — no second job.

"I'm past 40 — is it too late?"

It's the opposite. Training is built around longevity and joint-smart progression, so you get stronger while ageing well.

"I'm drowning in fitness data."

We turn the numbers into a few simple weekly actions. Less dashboard, more 'do this next'.

"I've tried before and it didn't stick."

A real coach plus an accountability system keeps you consistent when motivation dips — that's what actually moves the needle.

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From skeptics to believers

“

Finally, someone who explains the 'why' behind every recommendation. I've tried 5 different programs — this is the first one that actually made sense.

Marcus K.
Consultant, 34
+8 kg lean mass
“

Very quickly I understood that I had been missing deeper clarity on how to train for glute gains.

Dana M., 27
Fitness Enthusiast
Visible glute transformation
“

I was skeptical at first — I thought I knew enough. Turns out I was leaving so much on the table with nutrition timing alone.

David R.
Entrepreneur, 38
22% → 15% body fat
Meet your coaches

Science and results without the jargon

Alonso Prieto

Alonso Prieto

Founder of UnderForge®. 15+ years calisthenics & gym, entrepreneur, human flag holder. Discipline. Systems. Results. Let's build something extraordinary.

Discover

Evidence-based guides

Building Muscle After 40

Muscle is not just about looks after 40 — it is the organ of longevity. Here is how to build it safely and keep it.

Read →

Strength Training for Longevity

Strength is not vanity — grip strength, muscle mass and the ability to get up off the floor track with how long and how well you live.

Read →

Evidence-Based Fitness Coaching

The fitness world is loud. Evidence-based coaching cuts through it with the few principles that actually move the needle.

Read →
All guides →

Ready to forge your best self?

Apply now →

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