Purpose: The aim of this study was to investigate the effects of coaching the Australian recommended fundamental overarm throwing skill criteria for less-skilled adolescents on movement competency using three-dimensional (3D) motion analysis. Methods: Less-skilled non-sports-active and skilled sports-active pupils were assigned to FMS Group (n = 97) and Sports Group (n = 129), respectively. Demographic, anthropometric, whole-body kinematic (discrete and time-series angular displacement and angular velocity data), motor coordination (segmental sequencing) and motor performance (maximum ball release speed) were analyzed. Baseline data were compared using independent T-tests and Chi-Square tests; interaction effects were assessed using repeated-measure ANOVAs. Changes in time-series kinematic data were analyzed by comparing the areas enclosed by the 95% confidence intervals. Results:There was merely a modest improvement in motor competency for the less-skilled pupils. The FMS group significantly acquired 13/75 discrete kinematic variables (p < .01) and four movement patterns but not motor coordination (p = .469) and motor performance (p = .756). Prior to the intervention, the pupils acquired 4/7 recommended skill criteria. The descriptions of another three criteria were not appropriate with no improvement in motor coordination and performance. Two new skills were identified and improved after the FMS intervention. Conclusions: The recommended skill criteria for children were not developmentally and age-appropriate for early adolescents. The use of quantitative 3D motion data provided a more precise and developmentally applicable fundamental overarm throwing criteria than content validated skill criteria. The recommended skill criteria should be modified to facilitate teachers and coaches for effective education.
Keywords: Adolescents; biomechanics; coaching; efficiency of movement; fundamental movement skills; gross motor skills; motion analysis; physical education; quantitative.