Introduction to Sports Biomechanics: Analysing Human Movement ...

QUALITATIVE ANALYSIS OF SPORTS MOVEMENTS
Olympic Association, which I was privileged to chair in the early years of the millennium,
recognised this interdisciplinarity through the make-up of the group, which
included notational analysts, sports biomechanists and motor skills specialists, together
with coaches and performers.
The various approaches used by movement analysts have focused on biomechanics,
motor development or pedagogy, and have sometimes been cross-disciplinary. Previous
work has included development approaches, for example looking at whole-body
developmental sequences, as in the four stages of acquiring throwing skills, or adopting
a ‘movement-component approach’, focusing on the legs, the arms or the trunk. More
recent developments have included logical decision trees, as in Figure 2.1.
The focus has varied in the various pedagogical approaches. Sometimes the observer
has been recommended to attend to the temporal phases and spatial aspects of the
movement. Other approaches have integrated various disciplines, have considered the
pre-observation, observation and post-observation stages of analysis, and introduced
the concept of critical features – those that contribute most to successful performance of
the skill.
The various biomechanical approaches have typically identified the critical features
of a skill using ‘biomechanical principles’ (better called ‘movement principles’). These
approaches include POSSUM – the Purpose-Observation System of Studying and
Understanding Movement. In this approach, the movement is classified by its purpose,
as in Figure 2.2(a), which is associated with ‘observable dimensions’ of the movement
that the observer evaluates. In the example of Figure 2.2(a), the focus is a projectile –
the whole body of a sports performer or an object, such as a shot. If the purpose is
height, then the release or take-off is vertical; if the purpose is horizontal distance
(range), the release is around 45° (but see Chapter 4 for further consideration of this
point); if the purpose is speed, the release is nearly horizontal. The focus of the observer
can be on the whole body or on specific body segments. This approach was extended
around ten core concepts of ‘kinesiology’, as in Figure 2.2(b). Other biomechanical
approaches have also tended to be based on a list of movement principles, for
example Figure 2.2(c). It is instructive to compare such sets of principles, such as those
Figure 2.1 Simplified logical decision tree approach to qualitative classification of fast bowling technique.
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