Biomechanical insights into the interaction between acrobatic gymnasts performing partner-assisted flight

Abstract

This thesis investigates how the interaction between individual capacities, interpersonal coordination, and experience level influences performance in dynamic skills in Acrobatic Gymnastics. Twenty-one acrobatic gymnasts (12 bases and 9 tops), competing at national and international levels, participated in a laboratory-based data collection. Gymnasts performed individual assessments: bases executed medicine ball throws, and tops performed countermovement jumps. An inertial measurement unit was placed on each gymnast's sacrum. Then, they performed three pair tasks: vertical throws, back tucked somersaults and back straight somersaults. Data was collected using a motion capture system and processed with Theia Markerless software. The pairs were divided according to their training experience. Results from the vertical throw task showed that top gymnasts exhibited minimal independent motion, largely driven by the base's actions, and that experience level influences: i) the time delay between gymnasts' motion, ii) spatial-temporal variables, iii) mechanical efficiency and iv) interpersonal coordination. The rotational tasks exhibited a very high correlation coefficient (0.98), with no detectable time delays. Granger causality analysis did not provide conclusive evidence of directional influence. Kinematic data from an inertial measurement unit was significantly underestimated compared to the optical motion capture system. In conclusion, the pair's experience influences the interaction between gymnasts, particularly in the time delay between their movements, individual capacities, and interpersonal coordination during the vertical throw task. During rotational tasks, findings suggest that while gymnasts move in a highly coordinated manner, such synchronization likely results from learned motor patterns rather than active adaptation to their partner's motion. Furthermore, the differences between methods underscore the need to interpret inertial measurement unit data cautiously and encourage collaboration between gymnastics clubs and biomechanics laboratories. These findings can assist coaches in optimizing performance and enhance training strategies in acrobatic gymnastics.