David Donner Bsc MBCO is a fully qualified and practising Optometrist with more than a passing interest in Sports Vision. This blog looks at this captivating science and David relates his expertise in Sports Vision to the big sporting events happening around the world today!
Thursday, 19 January 2017
Thursday, 8 October 2015
Rugby World Cup 2015 - Back Row
All rugby players need to be able to tackle, but the back row probably put in
more tackles per game than most other players. So it seems reasonable to talk about
the visual requirements in tackling for back row players. These would also be
largely the same for other players, though the backs might be more likely to
find themselves isolated in a one-on-one situation.
Some of the most common mistakes made in tackling include: planting the
feet; not getting close enough; not driving in with the shoulder; tackling too
high; and getting the head in the wrong position.
The tackler will take responsibility for guarding a channel, so will be
looking out for potential ball carriers running into that channel. Once that
ball carrier has been identified, the tackler should immediately switch their
focus to the ball carrier’s core area (around the stomach), because where the
core goes, the player goes. The tackler might also start visualising the
tackle.
“Visualise” in this sense means much more than imagining what something
will look like: it’s more about imagining the feel of the shoulder making
contact with the target area. An early switch of focus to the core means that
the tackler will be able to react to a change in direction from the ball
carrier, but the initial visualisation might for instance involve the right
shoulder driving into the right thigh of the ball carrier level with the bottom
of the shorts. This clear preparation should ensure that the head is safely to
the side of the ball carrier, “cheek to cheek”. If the tackler drops their
head, or gets it on the wrong side, serious injury could result.
We are all naturally drawn to look at other people’s faces, and this is
why tackles are often attempted too high. So in training, it’s important that
players make sure that they make this early switch in focus and visualisation
each time, whilst ensuring that they do not drop their head.
At non-elite levels, you often see players planting their feet quite
wide apart, sometimes stretching their arms out to the side, supposedly making
themselves a more difficult target to avoid. But it’s very difficult to get any
power into the tackle from that position, and it’s also very difficult to react
to any late movement from the ball carrier. The tackler often ends up having to
dive to make a tackle. This is likely to be ineffective if high, and runs the
risk of their head getting in the way of a stray boot if the tackle is low. The
tackler is also vulnerable to the hand off if the ball carrier runs straight at
them because they are in such a weak position.
The tackler should aim to get their feet in close to the ball carrier,
so it’s essential to keep their feet “active” with small steps. One tip is to
imagine a hula hoop around the ball carrier, and if the tackler is aiming with
their right shoulder, they should try and get their right foot within that
hoop. Another tip when training is to get the tackler to keep their hands in to
their chest, and to push against a ball carrier without extending their arms,
which again ensures they’ve got in close.
As the ball carrier gets in range, the tackler dips the shoulder
(dipping the shoulder too early can expose the head), but it’s still essential
to keep the head up. So the eyes focus on the target before contact, and then
past the ball carrier when contact is made. The feet must keep moving with
small steps to drive through the tackle as the arms close around the ball
carrier. If the tackle is made from the side, the ball carrier’s own momentum
should cause them to fall over with the tackler on top.
David Donner
Wednesday, 30 September 2015
Rugby World Cup 2015 - Props
It is essential for their own safety that props have the correct body
alignment before the scrum engages. They can check, for instance, that their
back is straight by crouching alongside a mirror, at home or in the gym. They
can do this with their eyes closed, and then look in the mirror to see if the
correct position has been achieved, and the forces from the players behind will
be transferred forward in a straight line.
It can be really helpful to video one versus one scrums, so you can
check that they have maintained the correct position on engagement. The players
can view it themselves so they can confirm that there sensation of body
position matches the reality.
The position of the head and neck are vital as it’s very easy to get
into an unnatural position, and serious injury could result. Once the player is
in the crouched position, you can get him to stand up straight, but making sure
that his head and neck position are unchanged. Do they remain in a natural
position? If the neck is unnaturally forward or back it is in an unsafe
position.
One suggestion for finding the correct head position is to wear a pair
of sunglasses. In the crouched position, you lift your head up until you can
just see over the top of them. You check this as before by standing up and
seeing if it still in a natural position.
One technique that can be really useful for props to get maximum power
in the scrum is centring. This is a visualisation technique that involves
putting the focus on the centre of your body. This makes the player more
balanced, and therefore increases power, especially as the focus is on the area
where there are larger, more powerful groups of muscles.
Getting into the correct body position is also very important in
lifting at the lineout. A common fault is to allow the head to fall forward, so
that the arms cannot lift straight up but at an angle, with the resulting loss
of power and direction. Lifters also need to make sure that they keep forwards
to their fellow lifter. If they look up, they are almost certain to tip back a
bit and lose the ideal strong position for maximum lift.
David Donner
Thursday, 10 September 2015
Rugby World Cup 2015 - Hookers
In honour of the rugby World Cup, I thought I’d do a short series on the visual requirements for some of the different positions starting with the hooker.
When people talk of visual requirements, they usually refer to the visual requirements of the player - things like having good visual acuity and peripheral vision. I tend to approach it another way, by looking at the visual requirements of the sport itself.
For a hooker, one of the main requirements is to be able to throw a ball into a lineout in such a way that it can be caught by the intended player on your side, and not intercepted by the opponents. Of course, it’s not always the hooker’s fault when this doesn’t happen, as it’s very much a team effort between thrower, lifters and catcher, and also depends on the ability of the opposition to defend.
One of the main difficulties for hookers is that they don’t actually have a target to aim for. They’re aiming for a space above the catchers head. But if it’s a throw towards the back of the line out, they often have to throw the ball in a parabola to evade the opposition’s catcher in the middle. If that’s someone like Devin Toner, who’s nearly seven feet tall before he’s lifted, that’s not an easy task.
You can get hookers to practise their throwing by aiming at a mark on a post, and that would certainly be better than nothing. But the best way to practise getting the correct trajectory for deeper throws would be to throw the ball through a hoop. The hoop would be set at the height of the opposition’s front jumpers.
I’ve seen this done with a tyre suspended from the cross bar. But ideally you’d want this to be hoop on an adjustable stand, and you’d want a second one set for the height of your tail catcher. The hooker then practises getting the ball through both hoops. This can be done as an individual practice, just with one set of forwards, and as fully contested lineouts.
The hooker should also spend some time throwing whilst blindfolded, giving the brain a chance to concentrate on the kinaesthetic (muscle) feedback with each throw. The position of the hands holding the ball, especially the little finger, must be identical each time (see earlier blogs).
The visual requirements of hooking the ball are minimal, certainly at elite level, because there’s hardly any hooking these days. Put-ins are still as straight as a dog’s hind leg, so it’s more important to push than to hook the ball. I read that Sean Fitzpatrick used to practice with his eyes closed, so he could still hook the ball even if he couldn’t see it because he was pushed out of position by the opposition scrum. Unless or until referees insist on the put-in being straight, I can’t see many people practising that today.
David Donner
When people talk of visual requirements, they usually refer to the visual requirements of the player - things like having good visual acuity and peripheral vision. I tend to approach it another way, by looking at the visual requirements of the sport itself.
For a hooker, one of the main requirements is to be able to throw a ball into a lineout in such a way that it can be caught by the intended player on your side, and not intercepted by the opponents. Of course, it’s not always the hooker’s fault when this doesn’t happen, as it’s very much a team effort between thrower, lifters and catcher, and also depends on the ability of the opposition to defend.
One of the main difficulties for hookers is that they don’t actually have a target to aim for. They’re aiming for a space above the catchers head. But if it’s a throw towards the back of the line out, they often have to throw the ball in a parabola to evade the opposition’s catcher in the middle. If that’s someone like Devin Toner, who’s nearly seven feet tall before he’s lifted, that’s not an easy task.
You can get hookers to practise their throwing by aiming at a mark on a post, and that would certainly be better than nothing. But the best way to practise getting the correct trajectory for deeper throws would be to throw the ball through a hoop. The hoop would be set at the height of the opposition’s front jumpers.
I’ve seen this done with a tyre suspended from the cross bar. But ideally you’d want this to be hoop on an adjustable stand, and you’d want a second one set for the height of your tail catcher. The hooker then practises getting the ball through both hoops. This can be done as an individual practice, just with one set of forwards, and as fully contested lineouts.
The hooker should also spend some time throwing whilst blindfolded, giving the brain a chance to concentrate on the kinaesthetic (muscle) feedback with each throw. The position of the hands holding the ball, especially the little finger, must be identical each time (see earlier blogs).
The visual requirements of hooking the ball are minimal, certainly at elite level, because there’s hardly any hooking these days. Put-ins are still as straight as a dog’s hind leg, so it’s more important to push than to hook the ball. I read that Sean Fitzpatrick used to practice with his eyes closed, so he could still hook the ball even if he couldn’t see it because he was pushed out of position by the opposition scrum. Unless or until referees insist on the put-in being straight, I can’t see many people practising that today.
David Donner
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).

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.
Tuesday, 30 June 2015
Mind The Gap
A new batsman comes to the wicket. He surveys the field,
making a careful note of the fielders’ positions. After blocking a few
deliveries, he starts to play some more expansive shots, and hits them,
unerringly, straight to the fielders.
From a ruck, the ball is passed to the first receiver who
runs forward a couple of steps before being driven back in the tackle by two
defenders.
A succession of crosses and corners fail to beat the first
defender. When the winger does finally manage to locate his centre forward, the
latter isn’t able to generate enough power in his header to trouble the
goalkeeper.
What’s going on? The answer is that each player is telling
his subconscious brain to pay attention to the position of the opposing players
(or his own player in the last example). The brain is then told what skill to
execute. The task is then carried out using those visual cues as targets.
Even if you told your brain something like “Don’t hit the
ball to the fielder”, the subconscious brain, which doesn’t understand spoken
language very well, just hears “hit – ball – fielder”.
The answer, if you’re a coach, is not to tell your players
to look for where the fielders/defenders are, but to look for where the gaps
are. So a new batsman would survey the field looking for those gaps, and maybe
start visualising hitting the ball into those gaps. In net practice, you can
put markers on the net to indicate fielding positions. But if the batsman
doesn’t seem good at avoiding them, you might want to highlight the gaps between
them using coloured markers.
You might also want to remind your players that cricket,
rugby and football pitches are pretty large compared to the size of even
adults. If they were a bird flying over the ground they would see lots of gaps.
So in cricket, if there are few gaps in a ring of close fielders, they need to
think about how they could safely hit the ball over them into those gaps.
Imagining they were high above the ground looking down might help them.
In sports such as football and rugby, the task for coaches
is to get their players to think of themselves as “space invaders”.
David Donner
Wednesday, 10 June 2015
The Problem With Cricket Nets
A few years ago I was umpiring a junior cricket match when a
young man came out to bat when his side was in trouble, having lost early
wickets for not many runs. He scored a rapid 50, which at least put his side
back in with a chance of winning.
You might think I’d be impressed by this innings, yet I felt
it encapsulated what is wrong with a lot of traditional coaching. Because
whilst there were a lot of impressive strokes to the boundary, there were also
a lot of horrendous misses and streaky edges (as well as a couple of dropped
dolly catches).
It seemed to me as if nearly all his shots were
pre-meditated, and I just had the impression that this was someone who spent a
lot of time practising in nets, especially against a bowling machine. He
clearly had a good eye, but had no idea how to build an innings, and wasn’t
using all the available visual cues that are required for good decision making.
The great players in the past have generally learned their
cricket by playing games in the street, park or beach. This meant that they
could spend many hours developing their technique by self discovery, rather
than learning to play in the way that a coach thought they should. But also, by
playing games these players were able to develop the mental side of the game, as
well as the ability to deal with unexpected challenges.
One cricket academy that tried to introduce a more
game-centred approach was the Cricket Australia Centre of Excellence in
Brisbane. They reduced the field of play to a 30-metre circle, marked by a low
net. This meant that they could play games in which everybody was involved, but
it also meant that they could put in a variety of conditions to challenge the
players and develop their skills. For instance, the batsmen would have to hit
the ball into specific zones in order to score runs. They could alter the sizes
of bats and the types of balls, and make any number of changes to the rules of
the game.
This type of approach can be used in most if not all sports.
Although the method of learning is self discovery, the coach still has a
crucial role to play, not least in setting up the game conditions, but also in
using techniques such as questioning and feedback to aid that process of skill
development.
More on feedback in cricket next time.
David Donner
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