Top athletes do not have sharper eyesight than athletes who compete at lower levels. Their advantage lies in visual skills that have to work at speed. A study of 598 athletes, led by researchers at the Second Faculty of Medicine of Charles University in Prague, found that professionals outperformed nonprofessionals on 6 of 10 visual-motor measures, including depth perception, reaction time and tracking several moving objects at once. On visual clarity and contrast sensitivity, the two groups did not differ.