Introduction to Sports Biomechanics: Analysing Human Movement ...

INTRODUCTION TO SPORTS BIOMECHANICS
Figure 4.15 Angular orientation showing angles of somersault (φ), tilt (θ) and twist (ψ).
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SUMMARY
In this chapter, we covered the use of videography in the study of sports movements,
including the equipment and methods used. The necessary features of video equipment
for recording movements in sport were considered, as were the advantages and limitations
of two- and three-dimensional recording of sports movements. We outlined the
possible sources of error in recorded movement data and described experimental procedures
that will minimise recorded errors in two- and three-dimensional movements.
The need for smoothing or filtering of kinematic data was covered and the ways of
performing this were touched on. We also outlined briefly the requirement for accurate
body segment inertia parameter data and how these can be obtained, and some aspects
of error analysis. Projectile motion was considered and equations presented to calculate
the maximum vertical displacement, flight time, range and optimum projection angle
of a simple projectile for specified values of the three projection parameters. Deviations
of the optimal angle for the sports performer from the optimal projection angle were
explained. We looked at the calculation of linear velocities and accelerations caused by
rotation and concluded with a brief consideration of three-dimensional rotation.