Dr. Jim & Sean
The Neural & Motor Units Behind (B)STRONG


Changing the world one muscle at a time…

We met in the early days of the first company Sean founded, AlterG Inc — developer of the Anti-Gravity Treadmill.  At the same time, Dr. Jim was a science advisor for the Nike Oregon Project, and evaluated the unweighting technology for use with the Nike athletes leading the Nike Oregon Project to become AlterG’s first partner.

Over the years we stayed in touch disscussing various advancements in the field of rehabilitation and human performance until one day Jim was introduced to the concept of BFR.  It didn’t take long to realize the potential or the concept for changing the way people train, recover, heal, and general stay healthy.

Nobody had optimized the technology for mass adoption!

With Sean’s decade of experience in entreprenuership, Jim’s 30+ years at the top of the medical and performance field, and a cameo appearance from Sean’s dad (NASA researcher, Biomechanics PhD, and original inventor of the AlterG), we set set out with the goal of making a system for EVERYONE.  We are very fortunate to have some of the brightest minds in the fields of strength and conditioning and physical therapy continuing to test and help us improve our products and services.  We view the concept of BFR as a full system composed of hardware and software ingenuity, scientific acumen, and vigourous yet simple education.  One of our goals at B STRONG is to mesh all these components into a system that follows our basic goals of:

Safe          Effective          Affordable        Easy-to-use       

VOILA!, B STRONG was born.

B STRONG has quickly grown to be the tool of choice for thousands of users around the globe since the official launch in early 2017, and we are fortunate and proud to call some the best athletes, coaches, doctors, and physical therapists in the world part of our family.

In late 2017, we partnered with Northeast Seminars to highlight the educaitonal component of the B STRONG system.  Through NES’s seminar and online learning platform, we will be teaching thousands of professionals and end users around the globe how to apply B STRONG to get the most of every session.

As the field develops, we are looking forward to continuing to use science, engineering, education, and our strong connection with the professional community to continue to make this amazing technology accessible for every human on the planet!

Change the world!  B STRONG!



Sean started his career in entrepreneurship straight out of Stanford University where he earned a B.S. in mechanical engineering and an M.S. in Management Science and Engineering. Sean spent 4 years playing Varsity Men’s Soccer learning first hand the fundamental importance of proper training and recovery. Sean’s first company, AlterG Inc, disrupted the world of un-weighting technology for sports performance and rehabilitation with its flagship product, the Anti-Gravity Treadmill. Through his experience with AlterG, Sean developed a passion for pushing the limits of performance and recovery, and providing those in need with tools to enable them to come back stronger than ever and pursue a healthy lifestyle.



Dr. James Stray-Gundersen, or Dr. Jim as we like to call him, received his Board Certification in General Surgery in 1985. He then completed Post Doctoral Fellowships in Cardiovascular Physiology and Human Nutrition at The University of Texas Southwestern Medical School (UTSW) where he received appointments as Assistant Professor in the Departments of Orthopedic Surgery, and Cardiology. While on faculty, over 20 years at UTSW, Dr. Jim conducted research and built and directed two World Class Human Performance Centers associated with leading hospitals, St. Paul and Baylor. Dr. Jim’s primary interest and area of research is human performance, the physiology of health and fitness/wellness through exercise prescription, markers of over training, nutrition as it applies to performance and health, altitude acclimatization and training (pioneered Live Hi/Train Low), and anti doping (developed anti doping test SAFE – Safe and Fair Events). Dr. Jim currently consults for the USSA in Park City, Utah where he operates a performance medicine clinic using B STRONG daily with everyone from olympic gold medalists to baby boomer retirees.

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