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Client Testimonials

In the beginning, I was so weak in my neck and core that I couldn’t even lift my head off the table. Jim put me through a sequence of muscle tests to identify which muscles were weak and whch needed strengthening. Then he prescribed a corrective series of exercises--a routine I could run through at home, three times a day until I was able to strengthen the muscles enough to begin a strength training program. I worked with Jim on a weekly basis in the beginning. Within a few months, my spasms had calmed down considerably, I lost twelve pounds, my strength and mobility had really improved, and that was just from the corrective exercise routine. 

Now I try to get to the gym four or five times a week. Many of the corrective exercises and drills now serve as my warmup routine. Jim put together strength training routine for me the consists of exercises that work groups of muscles together, in natural movement patterns, rather than isolating individual muscles for conditioning. Some of the exercises in my routine include dead lifts, squats, pistol squats, push-ups, weighted hip-hinge, and handstand push-ups.

Having never worked with a trainer before, I had no idea how valuable having someone watch and evaluate you can be. The smallest corrections in how to perform an exercise make a huge difference, and having a workout tailored to address my specific needs yields incredible results.

I am now able to work out on my own with the knowledge I gained from the sessions with Jim. I still need coaching from time to time be sure I am performing the exercises correctly, and to add additional challenges to my routine. Occasionally the spasms will return but I am usually able to get them back under control with some coaching from Jim. Clearly, it’s a work-in-progress, but the incredible improvements in strength and mobility I’ve experienced are a very strong incentive to stick with it.

Prior to working with Jim I had resigned myself to the belief that my age was beginning to limit my physical abilities. I couldn’t have

been more wrong! At 57 I am stronger and in much better shape than I was at 40, and I feel like I am just getting started!

To Core Dynamics and all that it may benefit:

My wife and I have been loyal Core Dynamic customers for the last seven years. Recently I made the commitment to obtain my business degree, so I neglected the gym and focused upon my studies. I went without the gym for roughly a year and a half and subsequently gaining more weight and becoming very unhealthy.

In January of 2015 I took the Biggest Loser Challenge and due to my new job hours I failed miserably and gained even more weight. When I reached the weight of 240 pounds I had decided this was enough. I recruited the help of an amazing trainer, Craig Priestly and the Core Dynamics nutritionist, John Erickson.

When I came back from my vacation in late March I started on my journey to shed the weight and in 3 months. I have shed over 30 pounds. I am attempting to reach my goal of 40 pounds as I am typing this letter.

The staff Core Dynamics have been very supportive, with well wishes from all of them along with my wife, but the motivation of my friend and trainer Craig, have help me tremendously and the suggestions and dietary advice of John have put me in a healthier and better place physically and mentally.


Thank you all.

James A. Vacey

Core Dynamics member Kerry Sharkey-Miller is a Sag Harbor-based photographer with an extensive background in fine art and media production. "When I was in my thirties, I owned and operated an art gallery and I worked out regularly before going to work. In those days I was in pretty good shape. In my 40’s I was teaching media arts full-time, and was spending less and less time working out. I spent long hours sitting at a desk working on a computer, and developed some pretty bad dysfunctional movements and had chronic muscle spasms in my back, neck and hands. At this point my workouts consisted mainly of cardio training on the elliptical machine. I was having a lot of trouble getting those spasms under control.  I wasn’t able to do much else. The spasms started to prevent me from being able to work for extended periods of time.  For a while I saw a physical therapist, until my insurance company cut me off. It was at that point, about a year and a half ago, that I approached the owner of Core Dynamics, Jim O’Hagan for help.

Hi Jim,

I wanted to thank you for your help and encouragement. A few days ago my son was asking about a membership at Core Dynamics and costs. I encouraged him to visit some gyms in our area and how important it is to exercise and stay fit.

He is 23 and needs to find a routine that he enjoys and can benefit from.

When I told him about Core monthly membership he thought that was expensive. I explained that there is a big difference between a real gym with a trainer and Planet Fitness.

You build a relationship with a trainer who is always there to help and guide you. Plus, Core has great members who support each other.

Thank you for being that kind of gym.



Hi Jim,


Thank you for today.  I came in feeling like 100  and left feeling 40. Thanks for the 60 years.  My right side feels alive!! Unblocked.
Your a genius!



I just want you to know that I thank my lucky stars that I met you. You are a very special person who knows how to work with those who work for you as well as your clients. I watch you with people like Larry with his vertigo, the man who broke his back falling from a mountain, and the man with one arm. I see how kind and encouraging you are with others and me. I know how hard you work to help me do better, and how we have created a warm relationship that means so much to me. I hope we can work together for years to come!


Thank you from the bottom of my heart for being you!!

Strength for Life


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