Analyzing force distribution in sports-equipment modifications: a paralympic cross-country sit-ski study

Abstract This study aims to understand how different seating configurations affect elite sit-ski athletes. The study applies a multi-sensor system to analyze knee, upper body, and gluteal loads in four set seating positions. This system provides a basis for monitoring muscle activation, symmetry, and technique. Findings reveal up to 31% (99 N) variations in knee force distributions between seating positions. There was up to 66% variation in applied right-to-left force distribution (43N RMSE to 71N RMSE), with min/max loads varying from 124 to 166N and 92 to 157N when going flat to uphill. Combined belt and seat force data show that abdominal activation levels impact performance. The most extreme variation in the seat ranges from –23N during flat to 427N uphill, leading to a 207% increase of RMSE (96–294N). For the same athlete and position, the load of the belt varied by 33% in RMSE (188N–250N) and with a min/max load varying from 91-328N to 75–439N when going from flat to uphill. The study shows the potential of customizing equipment and enhancing training by capturing real-time data and long-term monitoring progress through waveform analysis and comparison, using the technology to enable individualized adjustments for every disability. Overall, the study highlights the importance of personalized equipment and the use of a system of sensors to generate a holistic view to understand trade-offs and optimize equipment interaction. Future research should involve an extended training period with more athletes to assess the adaptation to load balance, reinforcing the need for personalized equipment in paralympic sit-skiing.