The CHIO Aachen, the second Rolex Grand Slam of Show Jumping Major of 2025, not only showcases world-class equestrian sport but also pioneers in championing horse welfare through science and innovation. At the heart of this commitment is the CHIO Aachen Scientist Circle – a groundbreaking, long-term initiative that brings together scientists and experts in the fields of horse husbandry and horse behavior from Germany and Switzerland. Their mission is clear: to understand and enhance the welfare of sport horses before, during, and after top-level competition.

Led by the CHIO Aachen Sports Director Birgit Rosenberg and a team of leading veterinarians including Prof. Dr. Dirk Winter and Dr. Miriam Baumgartner, the project has earned the support of the FEI, the Aachen Veterinary Office, and several environmental and regulatory agencies including The NRW State Office for Nature, Environment and Consumer Protection (LANUV).

At the heart of the project lies a central question: How are the horses really doing at the CHIO Aachen, and what needs to be done to ensure their long-term welfare? To answer this, a series of scientific studies are being carried out using state-of-the-art technology. AI-powered cameras developed by ACARIS are installed in selected stables both at riders’ home bases and on-site in Aachen which monitor movement, rest, eating, and drinking behaviour. Additionally, heart rate belts, stable air quality sensors, and faecal cortisol testing provide deep insights into both the physical and psychological stress levels of the horses.

Encouragingly, early findings show that although horses tend to spend more time in their stables during the show, they are kept active and well-exercised. Cortisol levels peaked slightly on competition days but showed no significant increases due to travel or training. Air quality in the stables consistently remained within animal welfare guidelines.

In 2025, the study will be expanded and now includes 16 horses from the disciplines of show jumping, dressage, eventing, and vaulting. New cameras focused on equine facial expressions – an innovative method of assessing emotional well-being. High-profile riders, including Rolex Testimonee Isabell Werth,Katharina Hemmer, and Felix Vogg are participating in this vital initiative.

The CHIO Aachen Science Lounge will continue to advance the dialogue by providing a forum for riders, grooms, trainers, veterinarians, and the media, where the latest insights and techniques for monitoring, training, and recovering horses will be discussed. The Science Lounge is organized by the CHIO Aachen CAMPUS in collaboration with ReproTraining.

Additionally, with an expanded sample size over three years, encompassing around 30 to 40 horses, the Scientist Circle aims to build a robust, science-based foundation for ongoing welfare improvements in elite equestrian sport – cementing the CHIO Aachen’s role not only as a world-class competition venue but also as a global leader in equine care.