
I’m going to tell you a couple of things about me that not all fitness trainers will tell you.
I never played sports in high school, I despised running a mile in gym class, and I have never been coordinated enough to excel at step aerobics or anything that requires a lot of rhythm or grace. I have always had to work HARD for things that come easy for some. I don’t say this for pity or as an excuse. I say this because it makes me a better trainer. I will never ask you to as a client to do anything that I wouldn’t or couldn’t do myself. Some trainers don’t have any clue what it’s like to be a “normal person,” (whatever that definition means anymore,) but I know what it’s like to struggle to find your fitness or to get your fitness back, because I’ve been in BOTH of those predicaments. It’s hard and sometimes you just need to take a deep breath and ask for some accountability from someone who will push you more than you feel willing to push yourself.
“WHO”
I help tired moms run again and regain their strength
Nikki Mueller, owner of Healthy Girl Fitness, LLC
- Certified AFAA Group Fitness Instructor
- Certified RRCA Running Coach
- Certified VDOT Running Coach
- Certified USA Fit Running Coach
- Certified ACE Fitness Nutrition Specialist
- Certified TRX Suspension Training Instructor
- Mobile Fitness Coach
- Personal Trainer for Body Balance Fitness Studio
- Race Director for the ORRC
- Gorgeous Guru for The Gorgeous Relay Series
- First Aid/CPR Certified
- Background in Pre & Postnatal Fitness Training
- Experience as a PNF Stretch Therapist
Affiliations
- ZYIA Activewear (independent rep)
- Stroops
- TRX
- Pro Ambassador Link (Use code TRXAMB10V2AC7X for 10% off)
- Four Sigmatic
- Affliliate Link (Use code "runlong" to save 10% off)

MY STORY
When people find out you’re a personal trainer, a fitness instructor, a running coach, or really anything in the health industry, there is a lot of assumption about the kind of person you are. I know this because I had some pre-conceived notions about trainers when I joined a gym in my 20’s at the lowest point in my life. My trainer was blonde, tan, fit, and bubbly. She was all the things that one would imagine a personal trainer to be, and she was amazing at what she did. Despite the fact that she seemedCata like the girl in high school who would never talk to me, I did what she asked of me, grew to trust her, and she made incredible things happen for me.
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When I started my fitness journey, I was overweight, depressed, and my confidence was at an all time low. I am grateful every day for being brave enough to step into that gym all those years ago because everything in me was terrified. I remember all the eyes on me in my cheap, cotton sweatpants and I was worried about the judgement that others would place on me. But I was ready for a change, and I decided that day that I was going to hire someone to help me take control over my life and I was going to do every single thing she told me to, because I didn’t want to waste my time or my money. And magically, it worked and I lost 80 lbs in a year by eating better and working out.
I also started running, and at first I couldn’t do a lap around the parking lot without getting horrible side cramps because I didn’t know how to breathe correctly. But I started with 3 minutes of walking on the treadmill and 1 minute of running, over and over. Then I gradually increased the running time and found myself able to run 3 miles. From there, I got up to 6 miles, then 10. I did my first half marathon in 2005 and my first full marathon in 2006. I ran 3 more marathons before getting pregnant.
Then I had kids. Though every pound I gained was worth the joy they brought me, I felt like my body had betrayed me. The things that had gotten easy were suddenly hard again. Doing 1 push-up was a challenge and I felt completely defeated. I was sleep deprived, emotional, and weak. I didn’t have the time or the energy to care for myself and I felt as though I was at the bottom of a hole with no shovel. When I finally looked up and saw the sunshine at the top of that hole, I decided to start digging in the dirt with my hands, so to speak. And with the support of some awesome other mommas, I clawed my way out. I found myself able to run short distances with the stroller and take less and less walking breaks. I saw my arms getting stronger and my clothes fitting better. Eventually, I was able to run marathons again, and I found myself faster than I’d been before kids. Things began to happen. All it took was time and putting one foot in front of the other every single day. I challenged my body over and over again. It was hard, but it was possible. I found myself in the best shape of my life. Ever.
After years of pushing myself to these limits, I came to the realization that I had some knowledge worth sharing with others. There are so many people out there who just need someone to believe in them and to guide them down the right path. Despite the fact that I was NEVER that person who stood up in front of a group, I got my AFAA certification and started training pregnant and postpartum moms as a group fitness instructor. And then I got certified by the RRCA to be a running coach too because I figured it was time to help others scale all those hills I’ve been running for so many years. After that, I got a certification in fitness nutition. I’ve had a lot of devotion to running, fitness, and nutrition because, quite frankly, it saved me.
I'm not here to "sell" you on anything. I'm not here to brag about my accomplishments either. I just want you to know that I've been there. I know how hard it is. I want to help others because I couldn't have done it without the help of others myself. I was terrified to put myself out there in the beginning, but I'm glad I did and I just want others to give it a try too. I've got some credentials, but it's honestly it's the life experience that I depend on to make me a good trainer.
If you want experience, I’ve got it. I have taken years of classes: boot camp, spinning/cycling, kickboxing, yoga, barre, TRX, core ball, circuit, and just about everything in between. In addition to this, I’ve run hundreds of races, including (but not limited to) trail ultras, marathons, half marathons, and more relays than I can count. I write for a running blog called “Run Oregon” and I get to test running gear and run more races than I ever thought possible. I’ve been on every side of the fitness game, from sitting on the sidelines embarrassed to an active participant, and finally to an encouraging leader. I’ve even taught classes and then handed my plan to other instructors and taken my own classes because I want to experience everything my clients do. My philosophy is that if it scares you, you need to do it. I have been in this business in one way or another for over a decade. I’ve been around the block and I can show you some things if you let me try!

I’ll meet with you for a complimentary half hour consultation to see if we’re a good fit for each other and to find out what your goals are. If you choose to hire me as your coach, I can either come to the location of your choice or you can come visit me at Body Balance Fitness Studio. I offer the following services:
- One-On-One Personal Training: You’ll get customized full-body workouts that focus on both strength and cardiovascular training. If you hire me to come to your home or to meet you at the location of your choice, you will primarily use your own body weight and some of my resistance bands for the exercise sessions, so fancy equipment is not necessary. If you choose to come visit me at Body Balance Fitness Studio, we will have access to the entire gym and all of the equipment there.
- Partner/Group Training: Have you ever had an accountability partner? Find some friends who want to join you and I can train you all for a more cost-effective option that’ll be fun as well as challenging. Similar in style to the one-on-one personal training, you'll get a full body workout with both strength and cardio training with the added benefit of friends!!
- HEALTHY GIRL GROUP TRAINING IN SW PDX AND TIGARD!! I'm currently teaching an outdoor Bootcamp at Gabriel Park on Wednesday afternoons at 4:00PM and on two Saturday mornings a month at 8:30AM and at Cook Park on Mondays at 3:30PM. Feel free to join the Healthy Girl Group Training Facebook Group if you are looking to join us and want to be kept in the loop on the schedule.
- Run Coaching: Whether you’re looking for one session or ongoing training, I can help you accomplish what you’re looking for to get you ready for a race or just to feel stronger running around your neighborhood.
- Group Run Coaching: Everything is more fun in groups, especially running! Have a friend or a group of running buddies do it with you and it’s like a weekly “friend date” except sweatier.
- Customized Plans: Are you training for a specific race? Trying to transition from one distance to another? Wanting to reach a new PR? I can build you a plan to get you there! If you want customized full body workout plans, I can help you with that too! I can also offer treadmill workouts and hybrid strength/treadmill workouts.
- 8 Week Run Training Program ON HOLD: I typically offer Fall, Winter, Spring, and Summer series sessions to get you race ready or just to have fun out there running with other like-minded people. This is an hour long class that meets once a week for 8 weeks and will cover things like speed work, hill intervals, and other tools to make you a stronger runner. Currently, things are on HOLD due to COVID-19. For more details, please reach out.
- 10 Week Family 5k Running Program: A running program for your whole family! Bring the kiddos to Vista Brook Park on Tuesdays and we'll run a 5k together at the end of the training! We'll be incorporating games and exercise into each session. This is recess mixed with a track session!
- Tuesdays from 3:30PM to 4:30PM at Vista Brook Park (6697 SW 88th Ave, SW PDX.)
- Begins January 5th and runs through March 9th.
- Register here
- Nutrition Planning & Guidance: Need help figuring out how to fuel your body safely and nutritiously? I'm your girll! Though I'm not a Registered Dietician, I am a Certified Fitness Nutrition Specialist and I can can give you some great tools to get your body feeling good inside and out.
- I also have experience as a stretch therapist, so if you need something stretched, just ask!!

CUSTOMIZED MOBILE FITNESS TRAINING:
I can come to you! I have some clients with small children and it’s just not feasible for them to go to a gym and have to find childcare, so I’m willing to come to their homes and train them while their little ones sleep or play. I also have a studio available to me if you're not sure where to meet, though availability is limited. I’m also happy to meet up with you at a park or another destination of your choosing. Gym equipment is not necessary, so consider me your mobile trainer.
Please note that I live in SW Portland, and I have some time constraints in regards to traveling too far. I prefer to work in the SW Portland/Beaverton/Tigard area, but feel free to contact me to see if we can work something out.
PERSONAL TRAINING AT BODY BALANCE FITNESS STUDIO:
Come see me at Body Balalnce, located inside Lincoln Towers near Washington Square in Beaverton. Body Balance is a small studio with all the ammenities you need in a gym. Come check it out at 10300 SW Greenburg Road #A, Portland, OR 97223 or give us a call at (503) 892-8870.
Currently, I also have these options available (as seen on the "What" tab):
HEALTHY GIRL GROUP FITNESS CLASS:
Come armed with with a water bottle and a yoga mat. I will bring the workout and we will stay socially distanced the whole time.You can also join the Healthy Girl Group Fitness Facebook Group if you are planning on joining us! There are two location and time options.
- SW PDX: Come to Gabriel Park and find us in the parking lot by the basketball court and playground off Vermont Avenue every Wednesday at 4:00PM and two Saturday mornings a month at 8:30AM.
- TIGARD: We'll meet at Cook Park near the main entrance bathrooms on Monday mornings at 3:30PM
10 WEEK FAMILY 5k RUNNING PROGRAM:
This is a running program for you and the kids! It's perfect for ages 5 years to 500 years old. This is the perfect running program for beginners and we meet rain or shine! There will be some fun games incorporated into the workout so everyone has fun!!
- SW PDX: January 5th through March 9th from 3:30PM to 4:30PM at Vista Brook Park (6697 SW 88th Ave, SW PDX)
GROUP RUN TRAINING PROGRAM: Currently CANCELED but stay tuned!

PERSONAL TRAINING & GROUP FITNESS TRAINING:
Strength and cardiovascular training are what I offer as a personal training instructor. I believe in doing whole body workouts rather than "leg day" or "arms day" workouts because I realize we have busy lives and we want it all. All of the workouts I plan outside of the Body Balance Studio are with resistance bands and body weight, so they can easily be done at home or on vacation without the need for fancy gym equipment. I also have a TRX system that I'm fully trained in and I can bring it to you if you want a great TRX strength workout. If you prefer a small gym setting, I can train you at Body Balance Fitness Studio. I'm offering an outdoor group workout at a couple parks as well. So many options!!
RUNNING COACHING:
As a running coach, I can train you both on a track and off. If you are looking for a hill workout, I'll take you there. If you want speed, we can do that too. If there's a specific race you are training for, let me know and I'll create a plan and work it around your schedule. If you are looking for a group to run with, I've got 8 week training sessions every season as well as weekend options for you to find people to sweat with.
NUTRITION SERVICES:
As a Fitness Nutrition Specialist who has also battled weight problems throughout my adult life, I'm here to guide you through your nutritional struggles. Whether you are trying to figure out what works best for your body in training for an event or you are just looking to gain more knowledge about food, I'm here to help you work through it.
I’m here to help you reach whatever goals you have, as your happiness is my ultimate objective. All my workouts are totally customizable to your needs.
My style is fairly laid back. My philosophy is that I’ll make you work as hard as you want to. If you want to put in the work, I’ll bring it. If you want to dial it back, I’ll help make that happen too. Ultimately, it’s YOUR workout, so you put in what you want to get.

It hasn’t been about being skinny for me in a long time. By the time I hit the age of 40, I knew that I no longer cared about fitting into cute size 2 jeans. I just wanted to feel good, healthy, and comfortable in my skin. That’s where the “Healthy Girl” creation came from, because that’s what I believe in. I knew I wasn’t alone and that I could help men and women out there who needed someone to offer them encouragement and support in a safe, judgement-free zone.
As cliché as it sounds, I started Healthy Girl Fitness because I truly want to help other people reclaim their bodies and their confidence the same way I did. I want to improve the lives of people who are willing to work for it. I spent so much of my life overweight and unhappy and I gained so much in taking control of my body. I want to help others achieve the same thing. Ask any of my clients or my friends and family and they will all tell you the same thing: I am passionate about this.
You think you can’t do it, but you just need someone to help prove that you CAN. And you WILL!!
Testimonials
Nikki is truly an amazing trainer. She has the perfect combination of passion, drive, and commitment to her clients. She knows just how to motivate and push, as well as offering encouragement throughout. Her professionalism, knowledge, and diverse training methods are the perfect scenario to achieve success and set a great foundation for a healthy lifestyle. She has my highest recommendation.
- Mindy
Highly recommend!
After my second child my core muscles were non-existent and I couldn't seem to find time to exercise. Then I ran into Nikki. As a mom, Nikki knows what areas I need to work on and what exercises it will take to get back in shape. She formulates workouts based on my needs and gives me homewok to help keep me on track. She is flexible and able to work with my busy schedule. My mental state, physical strength and endurance have all improved since I started working with Nikki.
- Karen
Training from a mom to a mom
There are not enough wonderful things I can say about Nikki Mueller and her training. I have taken both strength training classes and running training with Nikki and her subtle motivation flows throughout all fitness ventures. She is truly the "lead by example" type of trainer. Nikki's whole life is about bettering herself physically and creating a life worth being proud of, and that inspires me, everyday to get up and get moving! She motivated me through passively watching her live her fitness lifestyle to the fullest as well and actively, when she is pushing my to go "just one more mile"!
-Robyn
Glowing Review for Nikki's Training
Nikki is one of the most positive and motivating instructors I've had. While she is gentle and encouraging by nature, her workouts are rigorous and challenging. Nikki has high expectations for herself and those she instructs and her vast knowledge and personal experience guide her instruction.
- Karin
Group Exercise Instructor Recommendation
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