Author(s): CVJETICANIN, O., MARUŠIC, J., ŠARABON, N., Institution: FAKULTETA ZA VEDE O ZDRAVJU, UNIVERZA NA PRIMORSKEM, Country: SLOVENIA, Abstract-ID: 1635

INTRODUCTION:
The hip adductor muscle group plays an important role in mobility and stability of the hip joint during various athletic activities [1]. In sports characterized by high-speed movements and frequent changes of directions (e.g., football, ice hockey), injuries to the hip adductor muscles are common. Eccentric training has shown promising results in preventing muscle damage and reducing injury risk [2]. Given that commercially available devices for eccentric training of hip adductor muscles are often expensive and complex to use, thus limited in practical application, the objective of this study, i.e. project, was to introduce optimized training device, better suited for everyday use.
METHODS:
The development of the optimized training device (OTD) for eccentric hip adduction was split into two distinct phases. The initial phase centered on developing an adjustable sensory device (ASD) tailored specifically to validate functional requirements. During this phase, 12 subjects performed eccentric hip adduction with the ASD, providing insights into expected maximum torque produced across various exercise variations. Specifically, comparisons were made between long-lever (support above the ankle) and short-lever (support above the knee) variations, unilateral versus bilateral exercise, and different angles of hip flexion (0, 45, and 90 degrees). The data collected during this phase was used to optimize the design process for the first OTD prototype developed in the second phase of the project.
RESULTS:
The initial measurements conducted with an ASD provided crucial input parameters for the development of the first OTD prototype. The determined maximum peak torques from these measurements enabled the selection of an appropriate electric motor as the primary driving source for the device. Results of the measurements also revealed that maximal torque development occurred at hip flexion angles of 0 or 45 degrees, with a notable decrease in maximal torque observed at a 90-degree angle. Furthermore, we observed comparable torque production between long-lever (support above the ankle) and short-lever (support above the knee) variations of the exercise. Notably, the use of the short-lever variation allowed for the design of a more compact device in the initial prototype development process. Ultimately, the unilateral version of the exercise proved less viable, attributed to reduced torque output and the requirement for uncomfortable fixation methods. The aforementioned findings played a crucial role in the successful design of an optimized training device for eccentric hip adduction training.
CONCLUSION:
A novel solution for eccentric hip adduction training has been introduced. The initial prototype of the OTD was developed based on insights from measurements using the ASD. This developed OTD prototype stands out for its affordability, robustness, and user-friendly design, offering potential contributions to injury prevention across various athletic activities.