Train
Hard.
Train
Smart.
Underground Gym in Red Bank has been running small-group kettlebell training for adults 40+ since 2010. No fluff. No machines. Results that last.
4.9 stars from 105 members. The most-reviewed gym in Monmouth County for a reason.
Mon–Fri 6am–8pm · Sat 6am–1pm · 327 NJ-35, Red Bank
4.9★
Google Rating
105 reviews
14
Years in Red Bank
Est. 2010
57K
Facebook Followers
Real community
40+
Member average age
Built for adults
Verified Google reviews
4.9 stars.
105 real members.
"14 years in and Sergei still coaches every session like it's his first. I've trained at 'real' gyms. Nothing comes close to what Underground delivers."
Google Review
"I'm 54. I've never been stronger or moved better in my life. The small group format is exactly right — enough coaching, enough community."
Google Review
"4.9 stars across 105 reviews doesn't lie. This gym earns every one of them. Worth every dollar of the drive from wherever you're coming from."
Google Review
For members
Bring someone.
Earn a free month.
Underground Gym's Digital Guest Pass system lets members share a personal QR code. Guests land on a branded invite page. 3 successful referrals = one month free — tracked automatically.
- →Personal QR code generated in your member dashboard
- →Guests see 'Invited by [Your Name]' on arrival
- →Track every referral in real time
- →3 referrals = 1 free month, applied automatically
Your Guest Pass
Mike T.
2 / 3 referrals
1 more = free month
What we do
No machines.
No mirrors.
Real results.
Personal Training
One-on-one programming built around your body, your goals, your schedule. Sergei's coaching style cuts through the noise — no filler, just results.
Small Group Training
The Underground's signature format. 3–6 people, kettlebell-focused, coached with the same intensity as private sessions. Community without compromise.
Mobility & Fat-Loss Programs
Structured 8–12 week tracks that move fat, preserve muscle, and keep your joints healthy long-term. Built for adults who've been through the standard gym cycle.
Corrective Exercise
If something's been hurting, we find out why. Movement screening + targeted corrective work so you can train hard without breaking down.
Sports Performance Training
Power, speed, conditioning, and durability. For athletes returning to form or competitors looking to edge out the field.
Metabolic Assessment
Data-driven baseline testing to understand how your body burns fuel — so every session is optimized, not just busy.
The owner
Sergei Karaliou.
14 years.
No shortcuts.
Sergei opened Underground Gym in Red Bank over a decade ago with one conviction: most gyms are selling you a membership, not a result. The Underground was built differently — small groups, high coaching, real accountability.
The niche is intentional: adults 40+ who are done with injury cycles, done with unsupervised machines, and ready to train like athletes again. 105 Google reviews at 4.9 stars is what that conviction looks like over time.
Est. 2010
14 years in Red Bank
4.9★
105 Google reviews
40+
Primary client base
57K
Facebook community
Red Bank, NJ 07701
327 NJ-35
Show up
Ready to train
the right way?
Location
327 NJ-35, Red Bank, NJ 07701
Phone
732-693-0287Hours
Mon–Fri 6am–8pm · Sat 6am–1pm