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Chester County Press

Tonicity Fit

10/17/2018 12:04PM ● By J. Chambless

Lauren Giannini works out at Tonicity Fit, while owner and trainer Sarah Ostroski offers encouragement.

By Steven Hoffman
Staff Writer

“I've been planning this studio for the last 10 to 12 years,” said Sarah Ostroski, the owner and lead trainer of Tonicity Fit, as she looked out at her fitness studio that opened in August on Gay Street in West Chester.

It’s a Tuesday morning in September and Ostroski is in what she calls the assessment lab, a small room off to one side of the studio. This is where she meets with new clients to discuss their medical histories and to analyze their overall health and fitness levels.

“This is where the science starts,” Ostroski explained. “I like to say that, here, we're rooted in science, and everything we do is designed for life. The assessment lab is where the client and I really get to know each other. We need to be able to look out for any risks, so we go over the medical history and I will assess where they are on the pendulum of change.”

Assessment labs? Pendulums of change? Needless to say, Ostroski is not the typical personal trainer.

Ostroski is an American College of Sports Medicine nationally certified exercise physiologist. She holds a Bachelor of Science degree in Exercise Science from Eastern University as well as a Master of Science degree in Kinesiology: Integrative Exercise Physiology from Temple University. She is also an adjunct professor in the Kinesiology department at Eastern University, where she teaches courses such as strength training, concepts of fitness, and the physiology of exercise and aging.

She estimates that she has worked with more than 1,000 people on their training through the years, and while she was helping each one to improve, maintain, and enjoy a lifestyle of wellness, each person was also teaching Ostroski―she developed an understanding of how to train people with diverse strengths and weaknesses that need to be factored in.

At Tonicity Fit, everything is individualized, so Ostroski will talk to a new client in the assessment lab, reviewing the person's medical history so that everyone understands what that person's exercise needs are. She offers private and semi-private training, as well as some small group training sessions at the studio.

“I really like the small group training sessions because clients can be motivated by each other,” she explained. “And it's still easy to modify the training to fit what an individual needs.”

She prides herself on being able to develop a safe, effective program that will allow a person to reach his or her individual fitness needs.

One illustration of this is a student that Ostroski was teaching who had Type 1 diabetes. He was an exercise science major, but really didn't love exercise himself―he was afraid to really push himself because of concerns that arose as a result of his ailment.

“One day, I was asking the students in the class why they loved exercise, and I remember him saying that exercise was not his friend,” she explained. “With diabetes, especially Type 1, it's a slippery slope when it comes to exercise. He really felt like this metabolic disorder would control him.”

Ostroski met with the student, talked about his overall health and fitness, and started working with him to develop an exercise regimen that worked.

“I learned about his insulin pump, and we both made sure that we had sugar there,” she explained.

The student was able to feel a lot more comfortable when exercising, and his overall health improved.

“It really did change his life, and I feel really good about that,” Ostroski explained. “That's what I do this for.”

Another illustration of a client that Ostroski is proud to have helped is a professor who, at first, didn't necessarily like to exercise in the beginning. But she was a very motivated person, and when she went to the gym she would suffer small injuries because she was pushing too hard.

Ostoski worked with the professor to develop a plan for her diet and for exercise regimen. The professor ended up competing in a triathlon, and more than ten years later, she is still one of Ostroski's clients.

Ostroski is able to relate to her clients because, as a result of her own personal experiences and advanced training, she understands their hopes and their frustrations when it comes to maintaining a fitness regimen.

Ostroski grew up as an athlete. She trained as a dancer for more than nine years. Her father was a bodybuilder, and when she was growing up, she would often pick up the bodybuilding magazines to read about the exercise programs that were working for the athletes.

“I loved learning about their routines,” she explained. “And I found out that working out was a really good release for me.”

It was easy for Ostroski to grasp the importance of maintaining an active, healthy lifestyle.

“I found it for myself and my own journey, but I always liked helping others, too,” she explained.

That led her to work as a personal trainer for seven years before she decided to pursue a degree. It was during the process of obtaining her degrees that she learned more about the science of exercising, but it was very valuable to learn as she worked with individuals―she has helped clients in a number of areas including weight loss and maintenance, muscular strength training, understanding and implementation of life changes, nutritional and hormonal balance, injury prevention and recovery, sports conditioning, and recovery and maintenance of a physical illness.

One area in which Ostroski has developed a special interest is in helping people to use exercise to delay the aging process. Aging is inevitable, but finding an effective fitness routine that works, and combining that with a proper diet can help a person achieve a healthy lifestyle.

“Research does find that regular exercise can stall some of the issues that come along with aging,” Ostroski explained. “Maybe those issues can't be avoided forever, but regular exercise will certainly help prevent issues with your knees and hips.”

Ostroski has also worked with a lot of women as they go through menopause, and she is well-versed on helping them adjust to changes that are taking place.

She is a big believer in the benefits of weight training, so she encourages all her clients to incorporate some weight training into their routines. She likes to keep the exercises simple, so when she was planning the studio, she knew she wanted the clients to focus a lot on using a training bench, a stepper, and dumbells.

“I want people to be able to work out at home, too,” Ostroski explained. “Part of my job is teaching them so that won't even need me.”

Ostroski said that she is very pleased with having her business in West Chester. She likes how there is a spirit of cooperation among the small business owners in town.

She also likes that she was able―after 10 or 12 years of planning it in her mind―to design the Tonicity Fit studio exactly the way that she likes it.

Ostroski selected equipment that would offer a wide variety of exercises to her clients. There is an ample supply of plate-loaded equipment for functional training. In another area of the studio, there are kettle bells, boxes, and ropes for training. There are treadmills, ellipticals, and cardio equipment. In the middle of the studio is the area for circuit training. There are also Smith machines which allow for several hundred different kinds of exercises. There are free weights and a very versatile piece of equipment called a functional training cable machine.

Mirrors are everywhere throughout the studio because they help people who are training to make sure that they are always following the proper form.

“I am a stickler for that,” she said.

There are lockers and showers for the clients because Ostroski knew that some people will be stopping by to train and before or after work and might want to freshen up. These rooms are all ADA-compliant.

With the studio designed exactly as she wants it and enough equipment to meet the needs of clients, the rest is up to Ostroski and the other trainers. As clients continue to train at Tonicity Fit, Ostroski does ongoing assessments, and she regularly talks with each person to make sure that they are meeting their fitness goals and building a more healthy lifestyle.

“Quality over quantity is what I always tell clients,” Ostroski explained. “Nobody is going to get hurt here. I want people to feel comfortable and motivated. I would like to hold clients to coming in twice a week. Three times would be best. This is about results. That is where the science is.”

More information about personal training and small group exercise sessions at Tonicity Fit is available at

To contact Staff Writer Steven Hoffman, email [email protected].