Taking sides
14 Jul 01
Does being right or left-footed favour a footballer, or would a
more balanced approach help? John Illman investigates
IT WAS A superb cross that landed near the penalty spot, a gift for
the unmarked centre-forward. The goal was wide open, the defenders
out of place and he was perfectly placed to take a shot with his left
foot. Unfortunately, like many football stars, a great striker with one
foot isn't always so hot with the other. He shifted his footing so that
he could use his dominant right, literally tripped over his own feet and
missed.
If Paul Morgan had his way, this would never have happened. A sports
psychologist and adviser to the Great Britain and Irish rugby league
teams, Morgan reckons that his nine-year-old daughter Natasha has
better bilateral coordination than most world-class soccer and rugby
players.
Morgan's boast is not as remarkable as it sounds. Natasha plays the
piano and does so, like all pianists, with both hands. Two-handed
practice helps musicians develop the kind of bilateral skills lacking in
sport, Morgan believes. He's now suggesting ways to take some of
the ideas from his daughter's piano lessons to the sports ground to
find how to play on natural variations in handedness, footedness and
even dominant eyes. His plan is then to design training regimes to
compensate for any weaknesses. It opens up a whole new range of
possibilities for tactical planning and sporting strategy.
The potential benefits of two-sided dexterity in sport are immense. In
cricket, ambidextrous fielders leave batsmen uncertain about where to
steer their shots. In rugby league, it is customary to put weaker
defensive players on the left-the opposition's right-because fewer
balls move this way. And in soccer, it's well known that forcing a
player with a weak left foot onto that side will render him ineffective.
All these considerations are taken into account in planning tactics.
But it needn't be that way. Improving the non-dominant side of a new
pupil is the starting point for every music teacher, says Morgan.
Youth sport coaches, he says, should be doing the same. "Most
coaches do not appreciate the significance of the relationship
between lateral preference and sporting achievement," he says.
To be fair, the relationship is far more complex than it might appear.
For a start, there are exceptions, such as David Gower, arguably the
most elegant batsman in cricket history. He bats left-handed, but
does everything else right-handed, showing that different motor skills
don't always reside in a single brain hemisphere. But Stanley Coren,
author of the book Left-Handers, and Clare Polac, his research
collaborator at the University of British Columbia, have found some
general trends which might help sportsmen and women work to their
strengths-and work on their weaknesses.
Coren and Polac measured the dominant hands, feet and eyes of 2611
people in 15 sporting fields, and found that different combinations
favoured different sports. Being a mixed-hander or footer, equally at
ease using left and right, clearly has advantages in sports like
basketball, football and rugby. Bilaterality was also a plus in hockey
or
ice hockey, where the player has to shift grip rapidly to power a shot
from the right or left. But racket sports such as tennis, squash and
badminton seemed to favour strongly or consistently handed players.
Hand-eye relationships also come into the reckoning. "Congruent"
hand-eye preference, where the dominant hand and eye are on the
same side, is associated with better performance in racket sports,
Coren explains. The larger field of vision covers the area where most
of the action occurs. If a player is cross-sided, with dominant eye and
hand on opposite sides, the racket is invisible from the dominant eye
for most of its swing. Because aiming is done with the dominant eye,
any small corrections in the racket's swing come quite late. But people
with crossed hand-eye preference seem to have better balance, and
so may be better suited to sports like gymnastics, running and
basketball.
Morgan hasn't yet found a way to retrain dominant eyes. But he has
begun to insist that his subjects practise with their weak hand or
foot. He's developed a training pack for teachers of 5 to 8-year-olds,
listing what he calls "multi-firing exercises" to promote sensory-motor
development. It's nothing complicated, just a regime of simple
throwing and catching using both hands, then the right hand alone,
and then the left hand alone. This is followed by kicking or passing
with the dominant and then non-dominant foot, rhythmically touching
the left knee with the right hand, then right knee with left hand, and
other such exercises.
It seems to work for musicians. A couple of years back, Lutz JÄncke
and colleagues, then at the University of DÜsseldorf in Germany,
showed that non-musicians had the largest asymmetry or discrepancy
between their hands; string musicians a smaller asymmetry; and
keyboard players, the least of all. And the earlier the musicians had
started playing, the higher their degree of mixed-handedness.
"It seems that early manual skills training interacted with development
of hand motor dominance, leading to improved performance of the
non-dominant hand," explains Morgan. "This is exactly the experience
of youngsters like my daughter." But the potential for improvement is
not restricted to the very young, he insists. "If unknown amateur
pianists can manage it, it should be a doddle for £25,000-a-week
footballers or top-class cricket and rugby stars."
It might sound great to have perfectly bilateral footballers and
cricketers, but does hard graft with the weaker side actually just take
up time that could be spent honing the natural talents of the
dominant side? Chris McManus, professor of psychology at University
College London and former co-editor of the journal Laterality, thinks it
might.
He points out a study of chimps that shows a disadvantage of
spreading the workload between two sides. Chimps get a large
proportion of their food by "fishing" from termite mounds, poking
pieces of grass into the mounds which the termites grab onto. Chimps
show handedness too, although right and left-handedness is equally
common whereas around 85 per cent of people are right-handed.
William McGrew and Linda Marchant, zoologists at Miami University in
Oxford, Ohio, found that chimps that used only one hand collected 30
per cent more termites than those using two. McManus says this
backs up the idea that it pays to specialise. "A footballer practising
with only one foot for twice as long may produce better results than
someone practising with each foot for half as long," he suggests.
You don't become ambidextrous if you learn to play the piano with
both hands, says McManus. "You don't even get transfer of training
between one skill for the two hands and another. We've looked at this
in studies with pianists and typists. But there are other things that
are transferred-motivation, discipline, enthusiasm and a willingness to
train," he says. "In the end I suspect this may be all it comes down
to."
John Illman is a medical journalist who is based in London
From New Scientist magazine, vol 171 issue 2299, 14/07/2001, page
36
© Copyright New Scientist, RBI Limited 2001