Meet The Team


Certified Personal Trainer 

My name is Jeremie Guarderas, Owner of Thunder Fitness​.  I am an ISSA Certified Personal Trainer, Certified USA Boxing Olympic Coach, Certified MMA Conditioning Coach, and a TFW Certified Coach and I have been taking clients/friends bodies to new levels since 2007.  

More importantly, I find the most interest in building relationships with our clients so that everyone actually enjoys the process on their road to results.

My approach is different from others in the fitness industry...


I think it's important to know that I do not have that "ALL BUSINESS" approach... So You should never feel intimidated to walk through our doors... 

My Vision

I'm more about creating a positive environment and since our gym is far more than just a business relationship, it's important to me that you understand and contribute to the positivity.

My Vision

I don’t believe anyone should ever feel discouraged about training regardless of what physical traits they have because in the end, the journey is well worth it and you’ll feel like a new person. That’s what I try to bring to the table, not just bettering ones physical health, but their mental health too because that’s where it all starts.


Certified Personal Trainer

My name is Austin Crist and I am a National Personal Training Institute certified personal trainer. I have been training clients of all ages for a number of years now getting them in the best shape of their lives. 


I discovered my love for personal training while I was playing sports such as football and baseball in high school. Being in the gym, helping my fellow teammates out, really gave me an enjoyment to help people out with their overall health. 


Certified Personal Trainer

My name is Kristine Casali and I am an ISSA CPT.  I am self-employed in a family business and a mother of two.  So I know how hard it is to balance a healthy lifestyle and make time for yourself.  I had always led an active lifestyle growing up as a competitive figure skater.  However, with college, then starting a career and family,  taking time for myself took to the back burner.

In 2009 after moving around to a few gyms I met Jeremie and began group training and personal training.  After 8 years of hands on learning I decided it was time to share my passion for fitness with others.  In December of 2017 I became a Certified Personal Trainer.

Some of my proudest accomplishments since I began training at Thunder Fitness has been completing two NYC marathons and more than a dozen half marathons.  My love of running has motivated me to start and unofficial TF running group that meets several times a week for a few miles before class. 

My lifestyle change since joining TF is also one of my proudest accomplishments as well. 

My Vision

My desire in becoming a CPT was to be able to use the knowledge and the years of experience to change the lives of others the way my life was changed.  I would love to add working with clients and achieving your goals as one of my accomplishments.