Introduction to Sports Biomechanics: Analysing Human Movement ...

INTRODUCTION
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two approaches. Finally, I present a cautionary tale of unreliable data as a warning to the
analysis of data containing unacceptable measurement errors, providing a backdrop for
the last three chapters.
Chapters 4 to 6 focus mainly on quantitative analysis of sports movements. Chapter
4 covers 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 will be considered, along with the advantages and limitations of
two- and three-dimensional recording of sports movements. I will outline the possible
sources of error in recorded movement data and describe experimental procedures that
would minimise recorded errors in two- and three-dimensional movements. The need
for smoothing or filtering of kinematic data will be covered, and the ways of performing
this will be touched on. I will also outline the requirement for accurate body segment
inertia parameter data and how these can be obtained, and some aspects of error
analysis. Projectile motion will be 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 will be
explained. We will also look at the calculation of linear velocities and accelerations
caused by rotation and conclude with a brief consideration of three-dimensional
rotation.
Chapter 5 deals with linear ‘kinetics’, which are important for an understanding
of human movement in sport and exercise. This includes the definition of force, the
identification of the various external forces acting in sport and how they combine, and
the laws of linear kinetics and related concepts, such as linear momentum. We will
address how friction and traction influence movements in sport and exercise, including
reducing and increasing friction and traction. Fluid dynamic forces will also be considered
and I will outline the importance of lift and drag forces on both the performer
and on objects for which the fluid dynamics can impact on a player’s movements. We
will emphasise both qualitative and quantitative aspects of force–time graphs. The
segmentation method for calculating the position of the whole body centre of mass of
the sports performer will be explained. The vitally important topic of rotational kinetics
will be covered, including the laws of rotational kinetics and related concepts such as
angular momentum and the ways in which rotation is generated and controlled in
sports motions. The use of force plates in sports biomechanics will be covered, including
the equipment and methods used, and the processing of force plate data. We will
also consider the important measurement characteristics required for a force plate in
sports biomechanics. The procedures for calibrating a force plate will be outlined, along
with those used to record forces in practice. The different ways in which force plate data
can be processed to obtain other movement variables will be covered. The value of
contact pressure measurements in the study of sports movements will also be considered.
Some examples will be provided of the ways in which pressure data can be
presented to aid analysis of sports movements.
Chapter 6 focuses on the anatomical principles that relate to movement in sport and
exercise. This includes consideration of the planes and axes of movement and the