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• Keep your eye on the ball, is one of the first pieces of sporting advice

• we are all given.

• Which seems pretty sensible, when facing an object potentially moving at 100 mph plus.

• But is it even possible?

• The average male tennis pro has a serve of around 125mph.

• Baseball pitchers are throwing on average a 100mph fastball.

• With cricket fast bowlers coming in at a pedestrian 85mph.

• But when considering reaction times, speed isn't the only factor,

• we have to take in to account the distance too.

• If we take tennis, and consider the server's height and position on the court, the ball

• has about 75 feet to travel towards the receiver. Wind resistance, air friction and the impact

• of hitting the surface will slow the ball by roughly half, by the time it reaches the

• receiver. Meaning the overall journey of the ball takes an estimated 700 milliseconds.

• For context, blink twice. That was 700 milliseconds.

• But consider now that it takes around 500 milliseconds for the brain to process information received

• from the eyes, and 25 milliseconds for the motor cortex

• to send a message to the arms and legs. It will take a further 150 milliseconds to

• swing the racquet, meaning the receiver has about 25 milliseconds to gauge the flight

• of the ball, and act accordingly.

• Decent odds if you're a fly, less so for a mere human.

• Now add to all this that it is extremely unlikely

• for the ball to be visible to the human eye until the point it crosses the net,

• which means the receiver really has only around 400 milliseconds to react.

• The maths just doesn't add up. If you watch the ball by the time you've

• swung the ball will be past you. For big servers like John Isner or present

• world record-holder Sam Groth the journey time from the net is reduced to about

• 300 milliseconds, less than half the time needed to judge and execute the shot.

• So watching Groth's delivery to get to it, is impossible

• You cannot be serious man

• And in order to return it, you'll need to predict where the ball is going.

• You cannot be serious!”

• Fortunately, your brain is able to do exactly that. With a little practice.

• While we've all heard that, practice makes perfect, well this is especially true for

• elite athletes. Where practice isn't just about technique

• but about cutting down on thinking time. Eight-time Grand Slam winner Andre Agassi

• says that his game was at its best when he was able to, stop thinking and start feeling.

• Stop thinking. Let things happen.

• Practice isn't just about improving your own game. It also helps you to understand

• The brain contains a catchily-named action observation network

• of linked regions, including the cerebellum, which governs motor control

• and the superior parietal cortex, that assists hand-eye coordination.

• The AON helps us recognise familiar patterns and anticipate future action.

• Like Ronaldo here, scoring in the dark. The more an athlete prepares and practices,

• the more effective the AON becomes. For example, in a football penalty shootout,

• even if the striker isn't known at all to the goalkeeper, they can still look for familiar

• gestures and body-shapes in the run-up to help with their prediction.

• Elite athletes show enormous capacity for making such predictions, with the best tennis

• players able to regularly anticipate the trajectory of their opponent's shot even before they

• make contact with the ball.

• So how does this even work? The eyes help to determine the trajectory

• of the ball through tiny, rapid movements known as saccades.

• When we look at a picture, our eyes establish multiple fixation points for us to focus on,

• to help us make sense of what we are seeing. When a tennis ball is struck, the brain is

• able to draw a line from point of impact, to where it thinks the ball is likely to be

• in future, creating, an imaginary fixation point.

• The eyes are able to track the ball along this path, and suddenly saccade away to this

• imaginary point, allowing the player to prepare for the shot before the ball has arrived.

• So with the right amount of training and mental preparation,

• returning a 125mph serve is a piece of cake.

• In theory.

Keep your eye on the ball, is one of the first pieces of sporting advice

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# Returning a pro tennis serve: just don't watch the ball

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joey joey に公開 2021 年 08 月 05 日