Matthews started researching several different sports and found different types of handedness in each.By the way,he uses 'handedness' to refer to the dominant side for feet and eyes as well as hands.Anyway,his team measured the hand,feet and eyes of 2,611 players and found that there were really three main types of laterality:mixed - you work equally well on both sides - both hand and eye;single - you tend to favour one side but both hand and eye favour the same side;and cross-laterality - a player's hands and eyes favour only one side but they are opposite sides.Let's start with hockey.Matthews found that it was best to be mixed-handed - this is because a hockey stick must be deployed in two directions - it would be a drawback to have hand or eye favouring one side.