Monrovia, California  ·  Weekdays 5am–11pm  ·  Weekends 6am–10pm
Since 1987 · Monrovia, CA

The ultimate iron playground.

FILLED WITH LOTS OF IRON TOYS FOR STRONG GIRLS AND BIG BOYS.

Month to month.•No enrollment fee•No annual fee
Since 1987Built on the iron
25Personal trainers
2–200 lbDumbbells
365 daysOpen every year
A gym built for training

Photo and Video Gallery

Click below to take a virtual tour of ULTRAFLEX FITNESS.

Member Benefits

  • Free high-speed Wi-Fi
  • Private parking
  • Locker rooms & showers
  • Infrared sauna
  • Huge free weight room
  • Cardio & open turf zone
  • 2–200 lb dumbbells & iron weight plates
  • Glute room with Glute Builder, BootyBuilder & Panatta machines
  • Hammer Strength
  • Flex Fitness
  • Cybex & FreeMotion
  • Nautilus
  • Arsenal Strength & Atlantis
  • One-on-one personal training
  • Juice bar & massage
  • Professional posing room
  • Active military discount
  • Free UltraFlex Fitness training & nutrition app with membership
Personal training at UltraFlex Fitness
The right coach makes a difference
One-on-one personal training

Personal Training

With 25 personal trainers, UltraFlex can help connect you with a coach whose experience fits what you want to work on. Start with a free consultation and tell us what you're looking for.

  • Contest prep
  • Rehabilitation
  • General fitness
  • Sports-specific
  • Senior fitness
  • Youth training
Request a free consultation ↗
From our members

The UltraFlex experience

★★★★★
“Solid gym, got myself a day pass to go check it out and I definitely did not get disappointed. Arsenal and Panatta equipment 10/10. Posing room 10/10.”
Mario Paz · Google · 2 months ago
★★★★★
“Great gym to work out in. Lots of resistance equipment, no judgement, free parking, friendly informed staff, trainers available. I’ve been a member for over 15 years.”
Marianne Wallace · Google · 4 months ago
★★★★★
“I have had the wonderful pleasure of being a member with UltraFlex gym for about 2 years now and it is my favorite gym in LA county! They have some of the best equipment, clean workspace, motivating energy, and everyone makes you feel so welcomed. Brian, Zac, and Kevin always go the extra mile to make this place awesome for their members! I would recommend this gym to anyone, anyday! Thank you guys!”
Leena Landeros · Google · 8 months ago
Read 4 more Google reviews
★★★★★
“I have been training at Ultraflex for over a year and I can see the thriving and supportive community that this gym has built. It is always clean and the staff and trainers are attentive and knowledgeable in meeting the members’ needs, whether it’s general information about health and fitness or prepping for a bodybuilding competition. I would recommend this gym to anyone who is ready to take their training to the next level.”
Richard Bailey · Google · 5 months ago
★★★★★
“Loving this gym, sometimes gyms with pictures and trophies on the wall can be intimidating, but all that melts away when you’re met with the kind and welcoming attitude of the owners and the front desk manager Kevin. Staff is beyond polite and really make you feel like you belong there. Very clean and tidy too.”
Abi Betch · Google · 7 months ago
★★★★★
“I’ve been at Ultraflex since the start of Covid, since it was one of the few gyms open. The environment this place has become is beyond what any other gym has offered. From management to Maria, the staff has been great. This place is constantly improving and bringing the best equipment for their members.”
Crystal Ramirez · Google · 8 months ago
★★★★★
“If you’re looking for a place that is consistently well-maintained and has a great atmosphere, this is it. It has a genuine community feel—welcoming, ego-free, and high-energy.”
Andrea L. · Google · 8 months ago
See all reviews on Google ↗
Straightforward membership

At UltraFlex we keep an honest price year-round so it’s always a good time to sign up.

We let our value market itself rather than marketing games.

  • Month-to-month
  • No contract
  • No enrollment fee
  • No annual fee
  • Guest privileges
  • Second-member options
View Membership Options & Join Online ↗
Come see us

Open 365 days a year

Weekdays5:00 am – 11:00 pm

Weekends6:00 am – 10:00 pm

* Hours subject to change on holidays.

Follow UltraFlex Fitness on Instagram ↗
Membership OptionsContact us