Done-with-you training at a done-for-you standard.

PREMIUM MEDICAL FITNESS

Private, one-on-one medical fitness in Stony Brook & Mount Sinai.

The expertise is ours.

The results are yours.

Our Programs

Private, one-on-one medical fitness — built around your body, your history, and your goals. Assessed, not guessed. Designed around you, not a template.

1-on-1 Training

Private personal training with a credentialed Fitness Specialist — never group, never shared. Every session built from your assessment and tracked in-app.

See training programs

RD-Led Nutrition

Nutrition led by a Registered Dietitian — individualized care built around your health history, labs, and training. From $90/week.

Explore nutrition

Elite Membership

Our most comprehensive experience — daily private sessions, concierge nutrition, unlimited sauna, DEXA benchmark, priority access. By invitation.

Explore Elite

Stretch & Recovery

Private 1-on-1 assisted stretch sessions to improve mobility, reduce tightness, and recover faster between training days.

See stretch sessions

The Medical-Fitness Standard

Assessed, Not Guessed

Redefine is a medical-fitness company — training grounded in evidence, built on assessment, and backed by credentials no commercial gym carries.

State-Backed

NY DOL Apprenticeship

The only gym with a New York State Department of Labor–approved apprenticeship — 2,000+ hours of training our Specialists complete.

Clinical Advisor

Amanda Teeple, NP

A board-certified Nurse Practitioner provides clinical input on our methodology, screening standards, and Specialist education.

Nutrition

Registered Dietitian–Led

The highest nutrition credential there is — individualized medical nutrition therapy within her licensed scope.

Measured

InBody & DEXA

Movement screening, body-composition scans, and reassessments on a set cadence. Every session tracked in-app.

Proven

1,000+ Clients

Private, 1-on-1, never group — a thousand-plus people rebuilt in our two Long Island studios.

Not Sure Where To Start?

Answer 6 quick questions and we'll point you to the program built for your body, your history, and your goals — in about 60 seconds.

Find Your Program →

ADVANCE COMMITMENT

Commit to your program with 12 weeks paid upfront, and unlock an exclusive menu of perks:

PERKS:

REAL PEOPLE. REAL RESULTS. 

See why clients trust Redefine. 

Brian B.

20:03 01 Sep 25

Had a 2 week experience in Redefine when over from UK. We were given a great welcome and encouragement. Targeted personal training for knee improvement was very professionally delivered - but always with a personal touch and empathy.
Well done Kyle and Hannah! And thanks!

Response from the owner 01:25 02 Sep 25

Thank you for sharing your positive experience, Brian! We're thrilled to hear that our targeted personal training for knee improvement met your expectations and that Kyle and Hannah provided such great support. Your kind words about our team's professionalism and empathy mean a lot to us. We look forward to welcoming you back on your next visit!Thank You

Ed A.

01:18 27 Aug 25

The trainers are very knowledgeable and personable. The equipment is well maintained and the facility is clean. However, the management is sketchy with their billing: Your sessions have an expiration date. They charge you to parse your account. It's a good business that is run poorly.

Response from the owner 21:53 27 Nov 23

Thank you for your kind words, Ed! We're thrilled to hear that you find our trainers to be knowledgeable and personable, and that you appreciate the well-maintained equipment and clean facility. We strive to provide the best fitness experience possible, and we're glad that you're satisfied with our efforts. Thank you for choosing Redefine Fitness, and we look forward to continuing to exceed your expectations! 💪🌟

Jameson K.

22:19 08 Aug 25

Kyle And Kolja Are The Best Trainers
I highly recommend them

Response from the owner 22:30 08 Aug 25

Thank you for your fantastic review! We're thrilled to hear that Kyle and Kolja made such a positive impact on your experience. Your recommendation means a lot to us, and we appreciate your support!Thank You

Chris R.

19:37 07 Aug 25

Redefine Fitness in Stony Brook is hands down one of the best gyms I’ve ever been to. The atmosphere is welcoming, the equipment is top-notch, and the whole place is always clean and well-organized.

But what really makes it stand out is the staff. Shoutout to Both Kyle and Kolja. They are incredibly knowledgeable and genuinely care about helping you reach your goals. Whether it's tweaking your form, answering questions, or just offering that extra bit of motivation, they’re always professional and approachable. They know what they're doing, and they make you feel confident and supported.

Response from the owner 19:47 07 Aug 25

Thank you for your wonderful review, Chris! We're thrilled to hear that you had such a positive experience at Redefine Fitness in Stony Brook. Our team, especially Kyle and Kolja, works hard to create a welcoming atmosphere and support our members in achieving their goals. Your feedback about our cleanliness and equipment is greatly appreciated. We look forward to seeing you continue on your fitness journey with us!Thank You

Sarah A.

21:20 23 Jun 25

awesome trainers! everyones great!!

Response from the owner 21:31 23 Jun 25

Thank you for your fantastic feedback, Sarah! We're thrilled to hear that you enjoyed your experience with our trainers. We appreciate your support and hope to see you again soon!Thank You

Lisa B.

13:07 22 Jun 25

I previously posted a positive review for my former Redefine trainer, Amanda. Now that she is in management and I have a new trainer, Hanna, it’s time I sang her praises!

I continue to be proud of myself for making the commitment to working out. This level of exercise and strength training has been the best gift I could ever give myself. I feel strong, sure-footed, and healthy.

I couldn’t do it though without Hanna! She might be young but she’s wise and sensible. We have such a nice rapport that I never hesitate to tell her if I’ve got some little issue troubling me because I know she will find a way to adapt my workouts accordingly. This is wonderful because it means that even if I’m not feeling 100% for some reason, most recently from jet lag, I can still get a good workout in. Most days I feel great and we get to it!

Hanna pushes me, just the right amount. And all the other trainers are so friendly, my little successes are often met with cheers from the entire staff. It’s really sweet, like all of Redefine is cheering for my success!

With this level of support from Hanna and the Redefine family, I know I will be a client for what I hope will be a very long, healthy life!

Response from the owner 20:14 25 Dec 24

Thank you so much for sharing your experience, Lisa! We're thrilled to hear about your journey and the positive impact strength training has had on your life. It's wonderful to know that Amanda and our team have been able to support you in achieving your personal goals. We look forward to continuing this journey with you in 2025 and beyond! Your success is our success!Thank You

V R

14:00 19 Jun 25

Been training here for over 2yrs and it’s been great. The trainers are knowledgeable and polite they’ve helped me work through past injuries. And the new faculty is nice and well equipped.

Response from the owner 14:11 19 Jun 25

Thank you for your fantastic review! We're thrilled to hear that you've had a positive experience over the past two years and that our trainers have been able to support you through your journey. Your progress and satisfaction are our top priorities, and we’re glad you find our new faculty and equipment beneficial. We look forward to continuing to help you reach your goals!Thank You

Why Redefine Exists

Built By Someone Who Needed It First

A college injury left founder Anthony Amen with five herniated discs, a concussion, and chronic migraines. Twenty-five doctors had no answer. Fitness did. He rebuilt himself — and then built Redefine so the next person handed a discharge sheet and no plan doesn't have to do it alone.

That story is the whole reason we assess like medicine, coach like someone who won't give up on you, and track everything to prove you're getting your life back.

Read our story The podcast & blog

Download our App

Download our Redefine Fitness app to manage your schedule, book sessions, and more!

TWO PRIVATE STUDIOS.

SAME PREMIUM EXPERIENCE.

PREMIUM MEDICAL FITNESS

Our Programs

1-on-1 Training

RD-Led Nutrition

Elite Membership

Stretch & Recovery

Assessed, Not Guessed

Not Sure Where To Start?

PERKS:

Built By Someone Who Needed It First

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Stony Brook

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Mount Sinai

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Strength Training for Shoulder Pain and Stiffness: An Evidence-Based Guide

Exercise for Knee and Hip Arthritis: A Strength Training Guide

Strength Training With Lower Back Pain: An Evidence-Based Guide

Strength Training and Blood Sugar: A Guide for Type 2 Diabetes and Prediabetes