The aim of this study is to compare and validate an Inertial Measurement Unit (IMU) relative to an optic system, and to propose methods for pattern recognition to capture behavioural dynamics during sport performance. IMU validation was conducted by comparing the motions of the two arms of a compass, which was equipped with IMUs and reflective landmarks detected by a multi-camera system. Spearman's rank correlation tests showed good correlations between the IMU and multi-camera system, especially when the angles were normalized. Bland-Altman plot, root mean square and the normalized pairwise variability index showed low differences between the two systems, confirming the good accuracy levels of the IMUs. Regarding pattern recognition, joint angle and limb orientation was respectively studied for 25 m during breaststroke swimming and 10 m of indoor rock climbing in athletes of various skill levels. Pattern recognition was also conducted on a macroscopic parameter that captured inter-limb coordination. IMUs revealed the potential to assess movement and coordination variability between and within individuals from joint angle measures in swimming and limb orientation time-series data in climbing.

No abstract

Abstract

Coaches and scientists share a preoccupation with understanding athletic performance. The aim of this study was to investigate coaches' practical knowledge about forward ice hockey skating with reference to the biomechanical research findings in order to improve understanding of the skating task and encourage the design of more representative research. For this purpose, 10 expert ice hockey coaches were interviewed. Semistructured interviews were transcribed and meanings units were selected and grouped to build the main categories after verbatim analysis. The qualitative analysis revealed that the coaches detailed forward skating based on three categories: posture, lower limb kinematics, and arm movements. They used performance indicators to specify their practical knowledge. These indicators were generally consistent with recent biomechanical research and when the coaches held different opinions, they expressed intuitive ideas that often suggested new research perspectives. This study illustrates how the interaction of scientists and coaches, via their respective knowledge, can supply new research perspectives.