Many injuries that occur during change of direction could occur to tissue damage caused by feeble coordination during the change. To prevent or reduce this risk when training for agility we need to focus more underlying movement principles that optimises coordination. One of the most important principles in agility is the “upper body first” or proximal initiation principle.
This principle of proximal initiation ensure increased pre-tension hence better tensegrity and concert the muscle fascial system for improved rapid dynamic stiffness and better dispersion of high forces, coming from the change of direction. The synchronization of shoulders and hips, stimulated by proximal initiation, also reduces rotational forces through the plant leg and hence could reduce the risk of ie ACL injury.
Like other skills this movement principle must be rooted in the system with effective variations and perturbations. The video below shows how Leigh Egger uses the hydrovest for perturbations and effective feedback from the water.