Phone: 339-337-8650

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Private 1:1 Fitness Training at Home, Outdoors & Online


COVID-19 Information

Sessions are currently being offered remotely and in person outdoors. Masks are required for outdoor consultations and sessions. Beginning on May 10th, I will resume in-home sessions on a client to client basis.


Is in-home training right for you?

  • Have you tried different diets and exercise programs but nothing seems to work? 

  • Do injuries or chronic pain keep you from working out? Do you struggle trying to find safe exercises to relieve your symptoms?

  • Would you like to work out more often, but with your busy schedule can never find the time? 

Private training that takes place in the comfort of your home has a higher success rate than other fitness programs because of increased accountability and support. For many, the hardest part of exercising is finding the time and motivation, and most people give up on their goals within three months of starting a program. Private and highly individualized in-home training eliminates the adherence barriers that account for lack of motivation to continue working towards goals, setting you up for success

Reach your GOALS!

Build strength, endurance, and flexibility

Address physical issues that negatively impact your daily routine or recreational activities

Learn how to adjust your diet and lifestyle to improve your health and feel your best!


 About me: Sasha Kossak


I have the best job in the world.


I spend every day helping others achieve their fitness goals and change their habits to achieve a healthier lifestyle and a greater sense of well-being.


I am a teacher, a mentor, and a constant source of accountability and inspiration to my clients.


I apply my extensive education and personal experience to help clients grow stronger and train more effectively for their specific goals in a way that minimizes their risk of injury and helps them move pain-free.


By leveraging the latest research and evidence-based strategies in exercise, nutrition, and therapeutic modalities, I create holistic programs that are highly customized to match individual needs and preferences. 


I consider it a privilege to help others, and feel no greater reward for my work than watching clients achieve their fitness goals and experience dramatic improvements in their quality of life. 



  • Rehab Fitness and Corrective Exercise Specialist

  • Master's degree from the Physical Therapy Program at MGH Institute of Health Professions

  • PROnatal Certified Pre/Postnatal Trainer

  • SCW Certified Wellness and Nutrition Coach 

  • American College of Sports Medicine (ACSM) Certified Personal Trainer

  • 4+ years of experience providing physical therapy treatment to patients in various settings

  • 10+ years of experience in the fitness industry. 



Testimonial from client

Dr. Matthew B.

Kate R.

“Sasha is the best personal trainer you could imagine. She is a fantastic professional as well as a wonderful person. As a trainer, she is highly competent and knowledgeable, attentive to your needs, and incredibly thorough in her approach. She will customize things for you depending on your goals, fitness level, current and past injuries. For example, I had a weakened pelvic floor after giving birth, and she managed to develop a plan that still resulted in amazing killer workouts that not only didn't cause me any issues, but led to the strengthening of my pelvic muscles. I used to be convinced that the only way to get a challenging and satisfying cardio workout was to run for an hour or two, and I did that for years. Sasha has taught me so many exercises that not only get your heart rate up, but are also massively more effective in engaging a wider range of muscle groups and toning you all over (something none of the standard cardio machines can accomplish!). And the best thing is that you can do them anywhere. Working out at a gym is great, but there is travel-time overhead, and sometimes (e.g., when you have a little baby at home) every 10 minutes count."

Evelina F.

“Sasha was a great help when I was having problems with my back. Not only did she have stretches to use in the short term and suggestions for exercises to use once my back was ready, but she was able to immediately relieve my pain using her manual skills. I have been to chiropractors, physical therapists, and others, and have never felt that kind of relief. The next day, my back continued to feel better.” 

 Catherine M.


“What impresses me most about Sasha is her dedication in helping me recover. She researched my condition exhaustively and tailored a program to my needs. She gave me print outs and instructions for stretches. When I was unwilling to give up certain physical activities she helped me find equipment and strategies that would lessen the impact to my injury. You won't find anyone who works harder to address your issues.”

Kieran W.

“I have suffered from back and shoulder pain and sciatica for over 30 years due to numerous sports injuries and finally a rupture of my L5/S1 disc [sciatic nerve].  I have seen literally every kind of practitioner there is and I have never felt the kind of relief I have after working with Sasha.  Her unique and gentle approach gave me immediate relief that has lasted for months now.  She used a combination of stretches, strength training and manual manipulation that addressed my multiple chronic symptoms.  She is thorough and spends as much time as needed designing a program that was unique to my specific problems.  I would recommend her techniques to anyone who has suffered with back pain or any other kind of ailments.”

Mitchell K.

"I've worked with Sasha to get relief from a sore lower back that has not let up for months. She is so easy to be with. I felt comfortable with her right off. She worked on relieving some of the pressure on my spine/pelvis, and gave me stretches to help work out and relieve my pain. After two sessions, I am starting to feel less sore. She has given me exercises to do in between and I plan to do them daily. Now I'm also looking forward to expanding our work together, as I feel stronger and my back improves, to include aerobic and fitness work as well.Working with a trainer in a gym just hasn't worked for me. I can't wait to work with her again. Having Sasha come to my house in this horrible cold weather has literally saved me!"

Pam S.



Fitness Training

Fitness training helps you achieve your personal goals and overall health through tailored exercise programs and nutrition and lifestyle coaching. 

Prenatal & Postnatal Training

Pre and post-natal training prepares women for the demands of pregnancy, childbirth, and motherhood. Exercises incorporated into these programs help to minimize pains and injuries and maximize daily function during pregnancy, facilitate easier childbirth, safely recover from labor, and return to favorite activities as soon as possible. 

Therapeutic Exercise

Therapeutic exercise is fitness training for anyone with physical constraints that make it difficult to exercise. My unique knowledge base and experience are essential for creating safe and effective therapeutic exercise programs. 

Active Aging- Fitness for Older Adults

As we become older, exercise and proper nutrition become even more essential for maintaining good health and improving quality of life. Fitness programs can differ greatly depending on medical and physical health, but often include exercises to improve mobility, proprioception, balance, strength, and cardiovascular fitness.



Please fill out the boxes below to book a complimentary initial consultation today! 

Serving the following MetroWest areas for in-home training:




















Please contact me if your location is not listed!

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© 2021 by Body In Balance, LLC