The A-Z of Sports Vision - Knowledge

Coaches are expected to give their athletes some feedback about their performance, and this can mean the athletes can gain different types of knowledge. Knowledge of results tells athletes how they have performed in relation to the goal they were trying to achieve, whereas knowledge of performance tells them about the quality of their performance, regardless of the outcome. Knowledge of results includes how far a long jumper has jumped, or the score of an archery shooter. Of course, there are many times when the result is obvious to the athlete, such as whether or not a shot has resulted in a goal or been saved. There are risks involved, however. For instance, a tennis player can see if their serve has landed in or out, and may be tempted to play safe and go for accuracy which may limit the development of their serve. Novice tennis players will know that they are hitting some shots harder than others, but are unlikely to have precise information about how fast the ball is travelling. Davies (1989) used an artificial method of giving this feedback so that the speed of the serve could be increased. The player served at a wall the same distance away that the net would be. Two lines were marked on the wall – one at the height of the net and another some feet higher, above which it had been assessed that the service would be “long”. The knowledge of results came in the form of the distance of the rebound from the wall. The player’s service speed rose rapidly, and the player was able to select for himself the most appropriate service technique. This is essential; otherwise when knowledge of result is withdrawn the performance will decline to its previous level since nothing will have been learned. Knowledge of performance might include the coach telling the player they should have passed the ball when they took a shot, or a technical comment about a bowler’s action. Video can be an effective way of giving athletes knowledge of their performance. I recently videoed some scrum halves passing the ball, and it was immediately apparent that they tended to kick their back leg out as they released the ball. This is clearly an attempt by the subconscious brain to retain balance, but it suggests that they are not as balanced as they should be in the first place. The trick now will be to get them to be more balanced without having to think consciously about their feet placement, as such an internal focus is likely to affect their performance adversely. I’d like to give them an image that would encapsulate the whole movement. By the time we get to “V for video”, I should know how successful I've been. David Donner