THE KINEMATICS OF INACCURACY IN BASKETBALL SHOOTING

Abstract

INTRODUCTION: A number of studies exist which detail the kinematic characteristics of successful basketball shots from a variety of distances (e.g., Miller and Bartlett, 1996). Unsuccessful shots, and their contributory factors, have received little attention. The objective of this study was to compare the kinematic characteristics and variability of successful and unsuccessful basketball shots. METHODS: Thirteen accomplished male basketball players participated in the study. Each attempted a sufficient number of shots from a distance of 6.40 m on a regulation basketball court until five successful and five unsuccessful attempts had been made. Shots were filmed using standard two-dimensional video recording techniques. Images were digitised at a sampling frequency of 50 fields per second, and incorporated fields prior to the first movement of the shooter and after ball release. Variability was measured using the root mean square error term from ANOVA. RESULTS AND DISCUSSION: [table] Results, shown in table 1, were unexpected. Slightly greater variability in release speed, angle and height - the primary factors determining outcome - was found for successful shots. Greater variability was also evident for successful shots in the angular velocity of the elbow and shoulder at release. The expectation that lower variability would be found for successful shots was only realised for hip and knee angular velocities. Findings are supported by recent evidence which challenges the widely-held belief that skilled performance is characterised by minimisation of variability. The data show that the selection of release parameters is both inconsistent and independent of outcome. This seems to be due, at least in part, to variability in joint angular velocities at release. CONCLUSION: It was concluded that variability in multi-segmental accuracy-based movements may not be an appropriate method of assessing inaccuracy, and that variability is apparently an integral aspect of such skills.