Addressing turning and direction changes when using the Bloomfield Movement Classification

Abstract
The Bloomfield Movement Classification (BMC) allows speed agility
quickness requirements as well as injury risk of activity in team games
to be characterised. A limitation of previous applications of the BMC is
that frequencies of movement types can be over-estimated while
duration of movement instances can be under-estimated. This is
because a movement instance composed of segments performed in
different directions and / or turning activity will be presented as separate
movement instances even if the same locomotive movement type is being
performed. The current paper proposes a method of processing data
captured using the BMC to address this. The method not only
recognises movement instances composed of multiple segments but also
allows movements to be characterised by the number of turns and
direction changes performed within the movement instances. The
netball movement data used in the current investigation has limited
reliability and the results should only be considered in the knowledge
that reliability is limited. However, the way in which the results are
presented here are a good example of how the BMC can be used in
future investigations of movement in different sports where a greater
level of reliability is achieved.