About Spraino

Our story

Spraino ApS was founded by MD Thor Grønlykke who made the first prototype of our ankle protection solution out of own need. When playing basketball as a medical student, Thor struggled with seemingly endless ankle injuries.

Knowing that the scientific literature pointed to high friction floors as a major problem, Thor analyzed where on the shoe’s sole the friction was deleterious. The answer pointed to the edge of the shoe, and the idea of putting a material with low friction on the outer edge of the soles was born. The low friction material allowed his foot to control the friction whenever his ankle came too close to twisting during play. Thor became completely injury free and to date he has never suffered another ankle injury.

Thor gathered that his findings should benefit other people other people as well and founded Spraino. Now Spraino is a company with several products, aiming to transform the markets for medical and sports footwear, providing value that goes far beyond what anybody would expect from a shoe.

Driven by science

At Spraino Aps, we firmly believe that advance comes through science. We work to expand the understanding of how mechanical properties of shoes translate into biomechanics and what the consequences are for human motion. Our unique focus is on understanding how controlling friction can impact biomechanical forces and shoe movements. In brief, we are creating a new paradigm for controlling the transmission of force between shoe and surface.

The results of our research is reflected in our product portfolio. However, there is an enormous untapped potential in addressing some of the largest public health challenges in our society.

We believe that performance in sports is highly impacted by friction. It is a widely held belief that high friction is a prerequisite for high for performance. We believe this is wrong, and we are working on proving it. We believe that excessive friction in the wrong places will not only lead to injuries, but also to isolated decreases in performance.

Our technology is not only making it possible to help people directly. Our materials technology and the experimental models developed in collaboration with our fantastic university partners, make it feasible to conduct experiments and create shoe properties that previously seemed impossible.

We have a long list of contributions to scientific journals and scientific conventions. We believe in open innovation and transparency – reach out to know more. We are interested in polymer materials science, mechanical engineering, biomechanics, shoes, sport performance models, and the many fields in medicine with lower extremity impact.


Spraino is committed to making a positive change for the environment and future generations. We want to make a good business by being a part of the solution in times of great challenge to our environment. We will therefore:

Work to be carbon negative including our suppliers’ carbon emission

Explore how we can be carbon negative taking into account all product life cycle impacts

Actively look to implement environmentally friendly and sustainable product solutions

Donate 10 % of our net earnings to charities that help diminish inequality in sports related health

Collaboration and Partners

Spraino is proud to be working with internationally renowned researchers and scientists at the Institute of Biomechanics at the German Sports College in Cologne, the Dept. of Orthopedics at Hvidovre University Hospital, the Department of Mechanics at the Danish Technical University, the Department of Orthopedics at Odense University Hospital, and Aalborg University.

Very close collaboration with excellent international researchers has made the all-important difference for us.

In biomechanics, Professor Uwe Kersting who is now leading the Institute of Biomechanics in German Sports College Cologne is our soul mate and we will always be grateful and hope to continue the exploration of our field.

In clinical sports rehabilitation, Professor Kristian Thorborg from the Department of Orthopedics at Hvidovre University Hospital has boldly set up and succeed in proving the clinical significance of friction control for injuries in a pivotal RCT study on ankle injury prevention.

We are also very proud of the fruitful collaboration with the Department of Mechanics at the Danish Technical University, the Department of Orthopedics at Odense University Hospital and Aalborg University as well as many national and international researchers who have contributed to our projects.

Also, we are an industry partner of the Team Danmark Sports Technology Network.

The company owes immense thanks to many people and companies in the local business ecosystem in Copenhagen. Many have been generous over the years, and some are still important supply chain partners.

Who we are

Thor Buch Grønlykke

Founder and CSO

20 years’ experience within sports medicine and medical technology development. Extensive public administration experience as elected and nominated representative.

M.D. (M.Sc. in Medicine)

Peter Sørensen

35 years’ experience in international B2B sales and management. Solid track record in scaling international businesses.

M.Sc. in Business Administration

Phillip Mondrup

Direct Sales Manager
Several years’ experience in online sales plaforms. Deep insight in SOME marketing.

General Engineering Student at Denmark’s Technical University