The last group is made up of those factors which are related to the game peculiarities influencing the motor skills to activate:
-the duration of the competition and the presence of breaks vary among different sports and obviously determine how long the athlete must keep the visual performance;
-the mental or physical stress which the athlete endures may have an effect on the performance. Stress, indeed, may act on the incoming visual information, by intensifying the restriction on perception. This evidence has lead the vision-care experts to consider stress as a condition in which visual abilities are highly activated;
-the degrees of predictability and stability of the environment in which the sport is performed influence the motor skill which is required (Schmidt e Wrisberg, 2006) and the most relevant visual abilities. An exchange in tennis and a counter-attack in a football match are two examples in which an open skill is required, because the opponent’s possible “movements” are unforeseeable.
Athletics’ 100 meters, swimming 100 meters freestyle, a dive from the diving-board or an exercise of physical training at the parallel bars, are all conditions in which the environment is stable and foreseeable and the skill required is closed. Open skills need a higher ability to adapt all of a sudden, hence dynamic visual skills and a fast elaboration of the information.
Edited by Fabrizio Zeri, source: P.O. Professional Optometry, August 2008