The Science of Canoeing By Richard Cox

Synergist (or neutralisers). Many muscles act over two or more joints. In certain co-ordinated actions, not all the
joints controlled by the prime mover may be required to move and a muscle or group of muscles is therefore
required to prevent any undesired joint movement For example, if a prime mover muscle flexes and rotates, but
only rotation is required, an extensor muscle might work statically to counter balance or neutralise the flexor
action of the prime mover. The action of the extensor muscle is known as synergic muscle action and makes the
prime mover more effective because the force of contraction is directed solely towards the desired action. In
extension of the shoulder joint during the pull phase the infraspinatus and teres minor contract to prevent inward
rotation.
Regardless of the movement or exercise performed, it will be appreciated that a vast and complex network of
muscular action takes place however simple the movement may appear. Often when people analyse a
movement, or devise an exercise to strengthen it, only the prime movers are given consideration. Similarly,
when attempting to define the action of a muscle, the many varied ways in which the muscle takes part are often
overlooked.
Before identifying the different joints and muscle groups employed in canoeing and the functions they perform,
one must first analyse technique. Before doing that, it would be helpful to learn how bodily movements are
described by the sports scientist. This will help one understand some of the terminology used later in the course
of the text
Movement Reference System
Planes
To describe bodily movements sports scientists first identify the plane in which they take place. Three planes,
each lying at right angles to each others are used.
Sagittal Plane
The sagittal plane is a vertical plane which passes through the body from front to rear as if bisecting it into two
37