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Circuit Three Fitness / Kickboxing

5 ★★★★★ 33 Google reviews · Kickboxing gym in Northglenn, Colorado

Kickboxing gym Beginners welcome Cardio kickboxing Private lessons Affiliated

Affiliated gym — reviews and the gym's own info suggest it belongs to a known kickboxing or boxing-fitness franchise or network (think 9Round, iLoveKickboxing, CKO, TITLE Boxing Club or Jabz). Franchise gyms run a consistent class format and are often a friendly, familiar place to start. If a specific brand matters to you, confirm it on the gym's own site.

Gym offering personal training as well as weights and cardio equipment.

Plan your first class

  • Beginner-friendly all fitness levels welcome, including total beginners — no experience needed, and you get in shape by training, not before
  • Cardio kickboxing classes high-energy cardio kickboxing on the bags and pads — a fun, sweaty workout built for fitness and weight loss, at your own pace
  • Private lessons one-on-one coaching available — a focused way to start or to work around a busy schedule; ask about availability and rates
  • Today see hours ·
  • Phone (303) 255-6004

Hours

Monday 6–9 AM, 4–6 PM
Tuesday 6–9 AM, 4–6 PM
Wednesday 6–9 AM, 4–6 PM
Thursday 6–9 AM, 4–6 PM
Friday 6–9 AM, 4–6 PM
Saturday Closed
Sunday Closed

Hours shift for holidays and class-schedule changes — worth a quick check before a special trip.

The classes they run

Kickboxing classes on the schedule at Circuit Three Fitness / Kickboxing, confirmed in members' own reviews and the gym's own info — not guessed from the sign out front.

🔥 Cardio Kickboxing 4 mentions

“I really do recommend Circuit Three to anyone trying to get into a new workout routine, very welcoming environment along with a great workout!”

All gyms that run cardio kickboxing →

🌱 Beginners 5 mentions

“The classes are customizable to any fitness level, beginner or expert and changed everyday which takes away the repetitiveness that some other gyms give.”

All gyms that run beginners →

🥊 Boxing 2 mentions

“I also do a weekly personal training session with Donnie and that’s where I can really get into more kickboxing and boxing fundamentals which is really fun!”

All gyms that run boxing →

👤 Private Lessons 2 mentions

“I also do a weekly personal training session with Donnie and that’s where I can really get into more kickboxing and boxing fundamentals which is really fun!”

All gyms that run private lessons →

Kickboxing Bootcamp

“The all the trainers hold the balance of support, motivation and knowing when to challenge you during your HIIT and kickboxing circuit!”

All gyms that run kickboxing bootcamp →

Other martial arts here

Kickboxing gyms are usually multi-discipline. Here's what else members mention training under the same roof at Circuit Three Fitness / Kickboxing — mined from their reviews and the gym's own info.

🥊 Boxing 2 mentions

“I also do a weekly personal training session with Donnie and that’s where I can really get into more kickboxing and boxing fundamentals which is really fun!”

Other gyms that also teach boxing →

Disciplines are mined from reviews and the gym's own info — they show what members have trained, not a formal class guarantee. If you specifically want muay thai, boxing, or MMA alongside your kickboxing, confirm the current schedule with the gym.

What members say

The things reviewers bring up again and again across 33 Google reviews — in their own words.

🌱 welcoming to beginners 8 mentions

“The classes are customizable to any fitness level, beginner or expert and changed everyday which takes away the repetitiveness that some other gyms give.”

🎉 fun, high-energy classes 5 mentions

“I never did kickboxing until 3 years ago when I joined and Donnie and Delanie progressed me based on my personal growth of the sport and it’s been so much fun.”

💦 killer cardio workout 7 mentions

“I really do recommend Circuit Three to anyone trying to get into a new workout routine, very welcoming environment along with a great workout!”

⚖️ great for weight loss 4 mentions

“They include weights, kettle bells, slam balls, kickboxing and other cardio equipment on various days, in multiple ways, to get the best results.”

🧠 builds confidence & relieves stress 2 mentions

“I can't stress enough how much I enjoy this part of my day and I really encourage anyone who is reading this to give it a try.”

🤝 friendly, family gym 6 mentions

“I really do recommend Circuit Three to anyone trying to get into a new workout routine, very welcoming environment along with a great workout!”

From the reviews

This gym has become part of my lifestyle. I'm able to hit the 30 minute workouts on my way home from work without feeling like I'm taking too much time away from my family. The workouts are a constantly changing mix of heavy bag kickboxing and weights (never boring or predictable).

★★★★★ — C, Sep 2025

I’ve been working out at Donnie and Delanie’s gym since I moved to Colorado 4 years ago and have followed them to their new gym Circuit Three when they opened. Best gym to be at, since it’s a small business that really pays attention to its clients!

★★★★★ — Maude, Mar 2022

I was always someone to workout at home and never had the desire to join a gym. Circuit Three has totally changed that and my feelings towards joining a gym. I checked out one gym before and had no desire to sign up because all they cared about was selling me a membership. Circuit Three was the exact opposite.

★★★★★ — Josh, Mar 2020

I have been with Circuit Three for about 3 years now and I can’t get enough. The owners, Donnie and Delanie, have mastered the art of cardio, weights, and overall fitness within the realm of kickboxing.

★★★★★ — Katie, Mar 2022

Excerpts from public Google reviews. Read all 33 reviews →

New to kickboxing? Start at Circuit Three Fitness / Kickboxing

Circuit Three Fitness / Kickboxing comes up as a beginner-friendly gym, going by their listing and members’ reviews. If you've never thrown a punch or a kick, that's exactly who a good beginners class is for. A few things worth knowing before your first week. First, you don't need to be fit or coordinated to start — you get in shape by training, not before it, and coaches scale every drill to you. Second, you won't be thrown into hard sparring — reputable gyms build the basics (stance, footwork, and punches and kicks on pads and bags) first, and any contact eases in gradually under a coach's control. Third, all fitness levels really are welcome — ask about a dedicated beginners or fundamentals class time so your first session is alongside others who are also starting out. Most gyms are happy to let you watch or try a class first, so reach out before you commit.

Call about beginner classes: (303) 255-6004

Your first kickboxing class at Circuit Three Fitness / Kickboxing

Nervous about walking into a kickboxing gym for the first time? Almost everyone is, and good coaches expect beginners to come through the door. Here's what to know. What to expect: a typical first class is a warm-up, then drilling the basics — stance, footwork, and punches and kicks on pads or a heavy bag — not hard sparring. Go at your own pace and rest whenever you need to; no one will bat an eye. What to wear: comfortable athletic clothes you can move and sweat in, and supportive trainers. What to bring: water, and hand wraps and gloves if you have them — many gyms lend loaner gloves for a first class, so it's worth asking when you call. As you keep training you'll add your own gloves and wraps (and shin guards once you start sparring). Sparring is optional and eases in gradually, once your basics are solid. Arrive 10–15 minutes early to sign a waiver and meet the coach. It gets easier fast — most people feel far more at home by their third class.

Kickboxing is a contact sport. Warm up, pace yourself, listen to your coaches, and if you have any injuries or health concerns, mention them before class and check with a doctor if you're unsure.

Where to find Circuit Three Fitness / Kickboxing

405 W 115th Ave Unit 1-B, Northglenn, CO80234

Get directions

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Listing verified July 2026 from public business records and member reviews. Something out of date? Report a correction. Own this gym? Claim your listing — it's free.