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 Training Programs

Welcome to Redefine Fitness, where transformation is personal. We specialize in expert one-on-one personal training and customized nutrition coaching designed to help you build strength, improve health, and create lasting lifestyle change. With two convenient locations in Mount Sinai and Stony Brook, NY, our dedicated Fitness Specialists deliver tailored programs, real accountability, and the support you need to redefine your fitness journey, one success at a time.

Designed around you, not a template.

Elite Memberships

Elevate your fitness journey with our Elite Unlimited Membership at Redefine Fitness in Mount Sinai and Stony Brook

Nutrition Coaching

Custom plans & accountability to support your training.

1:1 Training

Private, personalized coaching built for your goals

Stretching

1-on-1 stretch sessions to help improve your recovery and mobility.

Built For The People Other Places Turn Away

If somewhere else made you feel like you were too far along, too complicated, or not their kind of client, that is exactly who we built this for. Every program is one on one and built around your body, your history, and your goals. The same premium standard for everyone who walks in.

Trusted expertise. Recognized by New York State.

NYS Apprenticeship Program

Fitness Specialist

Trained through a New York State Department of Labor approved apprenticeship. 2,000 hours of supervised, on the job training plus 244 classroom hours.

1,000+ Clients Transformed

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

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

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

TWO PRIVATE STUDIOS.

SAME PREMIUM EXPERIENCE.

PREMIUM MEDICAL FITNESS

Elite Memberships

Nutrition Coaching

1:1 Training

Stretching

Built For The People Other Places Turn Away

Trusted expertise. Recognized by New York State.

Fitness Specialist

PERKS:

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