Build your career where strength meets purpose.
We're not a franchise. We're a coach-led gym that's been changing lives in Marsfield for over 10 years. If you care about real coaching — not just counting reps — you might belong here.
This isn't a regular gym job.
Coach, Don't Count
You won't stand around counting reps. Every session is coached, programmed, and intentional.
Learn From Day One
Work alongside experienced coaches who've been doing this for a decade. Not a YouTube education — a real one.
Small Team, Big Impact
We're small on purpose. You'll know every member by name and see the direct impact of your work.
Two ways to start.
Coaching Internship
For students and recent grads who want real gym floor experience — not just theory. Learn programming, coaching cues, nutrition basics, and client communication.
Learn more →
Personal Trainer
For certified PTs who want a supportive environment, real programming, and clients who actually show up. Bring your skills — we'll give you the platform.
Learn more →











Qualifications matter less than these.
You actually care
Not just about fitness — about people. The members who walk through our door are trusting you with something real.
You're coachable
Ego stays at the door. The best coaches we've ever had were the ones who never stopped learning.
You show up
Consistency over talent, every time. We'd rather someone reliable than someone brilliant who ghosts.
You want to grow
This isn't a parking spot — it's a launchpad. We invest in people who want to get better at what they do.
I started USG in a garage with one barbell. If you've got the hunger to learn and you genuinely care about helping people get stronger, I want to hear from you.— Coach Lenny, Founder
Ready to start?
Send us a message. Tell us who you are, where you're at, and why USG.
info@undergroundstrength.com.au