Thursday 30 July 2015

Facing a 90mph Fast Bowler

A recent Test Match Special podcast featured Simon Hughes talking to Jonathan Agnew about batsmen’s eyesight, and in particular how batsmen cope with facing a bowler bowling at 90mph.
                  
Any regular readers of these blogs will not be surprised to hear that elite batsmen don’t follow the ball all the way. In fact, they don’t even attempt to. Instead they make a jump or “saccade” to the part of the pitch where they expect the ball to bounce.
                  
Saccades are nothing exceptional. If you are reading a book, every time you get to the end of a line your eyes will make a saccade to get to the next line. During that period when your eyes are making these jumps, your vision will be blurred, but this is suppressed by your brain so you don’t notice it.
                  
There are several people researching this area in both the UK and Australia, but in my opinion the foremost paper was by Mann, Spratford & Abernethy (2013). They found that elite batsmen make two distinct saccades: the first one to predict where the ball will bounce; and a second one to the predicted contact area between bat and ball. This enabled them to align their gaze with the contact area on 100% of good length deliveries, and 90% of short length trials. By contrast, sub-elite batsmen could align their gaze to the contact point on only 13% of good length deliveries (and 80% of short length ones).

The authors suggest that these saccades don’t just happen because the ball is going too fast to be tracked by the human eye. In fact, Croft, Button & Dicks (2009) found that even when the ball was bowled at speeds low enough to be tracked, batsmen still made saccadic movements to the predicted pitch point. It’s suggested that this enables elite batsmen to use their peripheral vision to concentrate on the path of the ball either side of the pitch point. By observing closely how the speed of the ball varies before and after pitching, as well the bounce of the ball after pitching, they are better able to predict the position and timing of the contact point between bat and ball.

One important distinction between elite and club batsmen found by Mann et al was that whereas club batsmen aligned their eyes with the ball (less saccadic movement), elite batsmen aligned their head with the ball. They use the analogy of a miner’s lamp attached to the head, which would shine on the ball throughout its path for the elite batsmen, but not for the club batsmen. So for the elite batsmen, if they didn’t make any saccades, the ball would stay in the centre of their vision, assuming they kept their eyes still as their head followed the ball.

Even when the elite batsmen do make saccades, their head still stays in alignment with the ball, despite the ball being in the periphery of their vision. The authors describe this ability to couple the head to eth movement of the ball as an “important hallmark of expertise in batting”. This may be related to the fact that there are neurons in the brain that respond to the position of an object relative to the head, regardless of where the eyes are looking. The suggestion is that these elite batsmen can use this information about where the ball is relative to their head to predict where the bat/ball contact will be, so they only need to concentrate on when it will happen.

The BBC website (http://www.bbc.co.uk/guides/zy476fr) contains some suggestions from the likes of Graham Thorpe as to how to prepare to face bowling of 90mph. One suggestion is for the coach to use a side-arm thrower, which is a cricketing version of the ball thrower used for dogs in the park. What’s needed is a smaller version of this that fits onto a bowler’s hand, so the ball can be bowled with a normal action, but comes out much faster (without being a beamer).

Then, the answer to the question of how to face a bowler bowling at 90mph, would be to practise facing a bowler at 95 or even 100mph.