Football
Of all of the decisions parents face regarding
their children's future, choosing between shoulder pads or running
shoes for their Christmas present seems trivial. Well, according to
Kevin Reilly, president of Atlas Sports Genetics, this is a decision you should not take lightly.
"If
you wait until high school or college to find out if you have a good
athlete on your hands, by then it will be too late," he said in a
recent New York Times interview. "We need to identify these kids from 1 and up, so we can give the parents some guidelines on where to go from there."
In
December, Reilly's company began marketing a $149 saliva swab test for
kids, aged 1 to 8, to determine which variant of the gene ACTN3 is in their DNA. According to a 2003 Australian study,
ACTN3 was shown to be a marker for two different types of athletic
prowess, explosive power or long endurance. While everyone carries the
gene, the combination of variants inherited, one from each parent,
differs.
Science of success
The R
variant of ACTN3 signals the body to produce a protein,
alpha-actinin-3, which is found exclusively in fast-twitch muscles. The
X variant prohibits this production. So, athletes inheriting two R
variants may have a genetic advantage in sports requiring quick,
powerful muscle contractions from their fast-twitch muscle fibers.
In the ACTN3 study, Dr. Kathryn North
and her lab at the Institute for Neuromuscular Research of the
University of Sydney looked at 429 internationally ranked Australian
athletes and found significant correlation between power sport athletes
and the presence of the R variant. All of the female sprint athletes
had at least one R variant, as did the male power-sport athletes. In
fact, 50 percent of the 107 sprinters had two copies of the R variant.
What about those aspiring athletes that were not fortunate enough to inherit the R variant and its protein producing qualities?
North's
team also noted that the elite endurance athletes seemed to be linked
to the XX variation, although only significantly in the female sample.
In 2007, her team pursued this link by developing a strain of mice that
was completely deficient in the alpha-actinin-3 protein similar to an
athlete with an XX allele. They found the muscle metabolism of the mice
without the protein was more efficient. Amazingly, the mice were able
to run 33 percent farther than mice with the normal ACTN3 gene.
Cloudy future
Additional research is showing mixed results, however.
In
2007, South African researchers found no significant correlation
between 457 Ironman triathletes, known for their endurance, and the XX
combination. This year, Russian researchers at the St. Petersburg
Research Institute of Physical Culture also failed to establish the
XX-endurance performance link among 456 elite rowers but did find the
RR connection among a sample of Russian power sports athletes.
So, can we at least find the next Usain Bolt among our kids?
"Everybody
wants to predict future athletic success based on present achievement
or physical makeup. But predicting success is much more difficult than
most people think," Robert Singer, professor and chair of the
department of exercise and sport sciences at the University of Florida
warns in the book "Sports Talent" (Human Kinetics Publishers, 2001) by Jim Brown.
"There
are too many variables, even if certain athletes have a combination of
genes that favors long-range talent," Singer said. "A person's genetic
makeup can be expressed in many different ways, depending on
environmental and situational opportunities. Variables such as
motivation, coachability, and opportunity can't be predicted."
Destiny?
Just
as we assume that kids that are at the 99 percent percentile in height
are destiny-bound for basketball or volleyball, having this peek into
their genome may tempt parents to limit the sports choices for their
son or daughter.
Even Mr. Reilly expressed his concern
in the Times article: "I'm nervous about people who get back results
that don't match their expectations," he said. "What will they do if
their son would not be good at football? How will they mentally and
emotionally deal with that?"
For those parents that are just not ready to discover the sports
destiny of their child, or just want to save the $150, there is a much
simpler alternative. Hold your son or daughter's hand, palm up. Measure
the lengths of their index finger and their ring finger. Divide the
former by the latter. According to John Manning, professor of
psychology at the University of Central Lancashire, if the ratio is
closer to .90 than 1.0, you may have a budding superstar.
Manning explains in his aptly named new book, "The Finger Book"
(Faber and Faber, 2008),that the amount of a fetus' exposure to
testosterone in the womb determines the length of the ring finger,
while estrogen levels are expressed in the length of the index finger.
According to Manning's theory, more testosterone means more physical
and motor skill ability.
The digit ratio theory, as it
is known, has been the subject of more than 120 studies to find its
effect on athletic, musical and even lovemaking aptitude.
Don't
worry if the ratio is closer to 1.0, which is by far the norm. Plus,
you will be able to relax, enjoy your kids' sports events and only
worry about their genetic disposition to being happy.
Please visit my other articles on LiveScience.com and Sports Are 80 Percent Mental
As first seen on LiveScience.com
From the "athletes behaving badly" department (in the past month, anyway):
• NHL bad boy (Sean Avery) was suspended for six games for a crude remark.
• Six NFL players were suspended for allegedly violating the league's drug policy.
•
Another NFL player (Adam "Pacman" Jones) returned to his team's roster
after being suspended, again, for an off-field altercation.
• Oh, and NFL receiver (Plaxico Burress) accidentally shot himself in a nightclub with a gun he was not licensed to carry.
Despite
the 24/7 media coverage of each of these incidents, sports fans have
become accustomed to and somewhat complacent with hearing about
athletes and their deviant acts.
In fact,
new statistics reveal that bad behavior is clearly evident among high
school athletes, particularly in high-contact sports.
It starts young
Besides
the highly publicized stories, there are thousands more across the
nation involving amateur athletes taking risks both on and off the
field. From performance-enhancing supplements to referee/official abuse
to fights, guns and recorded crimes, the image of sports as a positive
influence on athletes may need a second look.
Granted,
in a population of any size there will be a few bad apples. However,
these actions have become so prevalent that academic researchers have
created a branch of study called "deviance in sports" attached to the
sports sociology tree.
They are
asking questions and challenging some assumptions about cause and
effect. Is there a connection between sports participation and
deviance? Does the intense competition and battle on the field shape a
player's off-the-field lifestyle? Since success in sports brings
attention and prestige to athletes, does the risk of losing that status
cause a need to take risks to maintain their "top dog" positions?
In their new book, "Deviance and Social Control in Sport,"
researchers Michael Atkinson and Kevin Young emphasize the confusing
environment surrounding athletes. They describe two types of deviance:
wanted and unwanted.
Owners,
players and fans may know that certain behaviors are literally against
the rules but are at the same time appreciated as a sign of doing
whatever it takes to win. Performance-enhancing drugs are not allowed
in most sports, but athletes assume they will improve their
performance, which helps their team win and keeps fans happy. Fights in
hockey will be, according to the rule book, penalized, but this
deviance is assumed to be wanted by fans and teammates as a sign of
loyalty.
However, related bad behavior can quickly turn on a player to being socially unwanted.
Abuse
of drugs that don't contribute to a win, (marijuana, cocaine, alcohol),
will transform that same player into a villain with shock and outrage
being reported in the media. In the Sean Avery example, a hockey player
fighting to defend his teammates on the ice can then be suspended from
the team and criticized by those same teammates for an off-color remark.
Real statistics
Most
athletes who make it to the professional level have been involved in
sports since youth. Sports sociologists and psychologists often look at
the early development years of athletes to get a glimpse of patterns,
social norms and influences that contribute to later behaviors.
In a recent American Sociological Review article,
Derek Kreager, assistant professor of sociology at Penn State
University, challenged the long-held belief that youth sports
participation is exclusively beneficial to their moral character
development.
With the focus on
teaching teamwork, fair play, and self esteem, sports are often cited
as the antidote to delinquency. But Kreager notes that other studies
have looked at the culture that surrounds high school and college
athletes and identified patterns of clichés, privileges and attitudes
of superiority. For some athletes, these patterns are used to justify
deviant behavior.
In fact, his
most recent research attempted to find a cause-and-effect link between
deviant behavior and specific sports. Specifically, he asked if
high-contact, physical sports like football and wrestling created
athletes who were more prone to violent behavior off the field.
Using
data from the National Longitudinal Study of Adolescent Health, more
than 6,000 male students from across 120 schools were included. The
data set included a wide collection of socioeconomic information,
including school activities, risk behaviors and at-home influences.
Kreager's study analyzed the effects of three team sports (football,
basketball, and baseball) and two individual sports (wrestling and
tennis) on the likelihood of violent off-field behavior, specifically,
fighting.
To isolate the effect
of each sport, the study included control groups of non-athletes and
those that had a history of physical violence prior to playing sports.
For
team sports, football players were 40 percent more likely to be in a
confrontation than non-athletes. In individual sports, wrestlers were
in fights 45 percent more often, while tennis players were 35 percent
less likely to be in an altercation. Basketball and baseball players
showed no significant bias either way.
"Sports
such as football, basketball, and baseball provide players with a
certain status in society," Kreager said. "But football and wrestling
are associated with violent behavior because both sports involve some
physical domination of the opponent, which is rewarded by the fans,
coaches and other players. Players are encouraged to be violent outside
the sport because they are rewarded for being violent inside it."
Sports Are 80 Percent Mental
Visit any youth soccer field, baseball diamond,
basketball court or football field and you will likely see them:
parents behaving badly. Take a look at this Good Morning America
report:
These
are the extremes, but at most games, you can find at least one adult
making comments at the referee, shouting at their child, or having a
verbal exchange with another parent. Thankfully, these parents
represent only a small percentage of those attending the game. Does
that mean the others don't become upset at something during the game?
Usually not, as there are lots of opportunities to dispute a bad call
or observe rough play or react to one of these loud parents. The
difference is in our basic personality psyche, according to Jay Goldstein, a kinesiology doctoral student at the University of Maryland School of Public Health. His thesis, recently published in the Journal of Applied Social Psychology
(see reference below), hypothesized that a parent with
"control-oriented" personality would react to events at a game more
than a parent with an "autonomy-oriented" personality.
According to Goldstein, defending our ego
is what usually gets us in trouble when we feel insulted or take
something personally. At youth sports games, we transfer this pride to
our kids, so if someone threatens their success on the field, we often
take it personally. The control-oriented parent is more likely to
react with a verbal or sometimes physical response, while an
autonomy-oriented parent is better able to internalize and maintain
their emotions. This "control" vs. "autonomy" comparison has also been
seen in research on "road rage", when drivers react violently to
another driver's actions.
Goldstein and his team focused their
research on suburban Washington soccer parents back in 2004. They
designed a survey for parents to fill out prior to watching a youth
soccer game that would help categorize them as control or
autonomy-oriented. Immediately after the game ended, another survey
was given to the parents that asked about any incidents during the game
that made them angry on a scale of 1, slightly angry, to 7, furious.
They were also asked what action they took when they were angry.
Choices included "did nothing" to more aggressive acts like walking
towards the field and/or yelling or confronting either the referee,
their own child, or another player/parent. 53% of the 340 parents
surveyed reported getting angry at something during the game, while
about 40% reported doing something about their anger.
There was a direct and significant
correlation between control-oriented parents, as identified in the
pre-game survey, and the level of angry actions they took during the
game. Autonomy-oriented parents still got mad, but reported less
aggressive reactions. As Goldstein notes, “Regardless of their
personality type, all parents were susceptible to becoming more
aggressive as a result of viewing actions on the field as affronts to
them or their kids. However, that being said, it took
autonomy-oriented parents longer to get there as compared to the
control-oriented parents.”
So, now that we know the rather obvious
conclusion that parents who yell at other motorists are also likely to
yell at referees, what can we do about it? Goldstein sees this study
as a first step. He hopes to study a wider cross-section of sports and
socio-economic populations. Many youth sports organizations require
parents to sign a pre-season "reminder" code of conduct, but those are
often forgotten in the heat of the battle on the field. Maybe by
offering the same type of personality survey prior to the season, the
"control-oriented" parents can be offered resources to help them manage
their tempers and reactions during a game. Since referees were the
number one source of frustration reported by parents, two solutions are
being explored by many organizations; more thorough referee training
and quality control while also better training of parents on the rules
of the game which often cause the confusion.
Sports contests will always be emotional,
from kids' games all the way up to professionals. Keeping the games in
perspective and our reactions positive are tough things to do but when
it comes to our kids, it is required.
Goldstein, J.D., Iso-Ahola, S.E. (2008). Determinants of Parents' Sideline-Rage Emotions and Behaviors at Youth Soccer Games. Journal of Applied Social Psychology, 38(6), 1442-1462. DOI: 10.1111/j.1559-1816.2008.00355.x
Sports Are 80 Percent Mental
Most baseball general managers live in obscurity most of their careers. Its
their first hire, the manager, that usually gets the red hot spotlight,
after every win and loss, second-guessed by reporters with recorders
and then later by fans. The GM puts the players on the field and lets
the manager and his coaches take it from there. Billy Beane
, Oakland A's general manager, could have also been an unknown, albeit
interesting, name to the baseball audience if it were not for author
Michael Lewis' 2003 book, Moneyball
. Moneyball was a runaway hit (even today, 5 years later, it is #19 on
Amazon's list of baseball books). It has morphed into a full-fledged
catchphrase philosophy used by everyone from Wall Street (where Beane
borrowed the concept) to business consulting. The general theme is to
find undervalued assets (ballplayers) by focusing on statistics that
your competition is ignoring. Of course, you have to believe in your
metrics and their predictive value for success (why has everyone else
ignored these stats?) The source of most of Beane's buried treasure of
stats was Bill James and his Sabrmetrics. Like picking undervalued
stocks of soon to explode companies, Beane looked for the diamond in
the dust (pun intended) and sign the player while no one was looking.
Constrained by his "small-market" team revenues, or maybe by his
owners' crowbar-proof wallets, he needed to make the most from every
dollar.
The combination of a GM's shrewd
player selection and a manager who can develop that talent should
reward the owner with the best of both worlds: an inexpensive team that
wins. This salary vs. performance metric is captured perfectly in this
"real-time" graphic at BenFry.com
. It connects the updated win-loss record for each MLB team with its
payroll to show the "bang for the buck" that the GMs/managers are
getting from their players. Compare the steep negative relationship
for the Mets, Yankees, Tigers and Mariners with the amazing results of
the Rays, Twins and Beane's own A's. While the critics of Moneyball
tactics would rightly point to the A's lack of a World Series win or
even appearance, the "wins to wages" ratio has not only kept Beane in a
job but given him part ownership in the A's and now the newly
resurrected San Jose Earthquakes of soccer's MLS. Beane believes the
same search for meaningful and undiscovered metrics in soccer can give
the Quakes the same arbitrage advantage. In fact, there are rumours
that he will focus full-time on conquering soccer as he knows there are
much bigger opportunities worldwide if he can prove his methods within
MLS.
In baseball, Beane relied on the
uber-stat guru, Bill James, for creative and more relevant statistical
slices of the game. In soccer, he is working with some top clubs
including his new favorite, Tottenham-Hotspur,
of the English Premier League. While he respects the history and
tradition of the game, he is confident that his search for a
competitive advantage will uncover hidden talents. Analytical tools
from companies such as Opta in Europe and Match Analysis
in the U.S. have combined video with detailed stat breakdowns of every
touch of the ball for every player in each game. Finding the right
pattern and determinant of success has become the key, according to
Match Analysis president Mark Brunkhart as quoted earlier this year,
"You
don't need statistics to spot the real great players or the really bad
ones. The trick is to take the players between those two extremes and
identify which are the best ones. If all you do is buy the players
that everyone else wants to buy then you will end up paying top dollar.
But if you take Beane's approach - to use a disciplined statistical
process to influence the selection of players who will bring the most
value - then you are giving yourself the best chance of success. Who
would not want to do that?"
Not to feel left out (or safe from scrutiny), the NBA now has its own sport-specific zealots. The Association for Professional Basketball Research (APBR)
devotes its members time and research to finding the same type of
meaningful stats that have been ignored by players, coaches and fans.
They, too, have their own Moneyball-bible, "The Wages of Wins " by David Berri, Martin Schmidt, and Stacey Brook. David Berri's WoW journal/blog
regularly posts updates and stories related to the current NBA season
and some very intriguing analysis of its players and the value of their
contributions. None other than Malcolm Gladwell, of Tipping Point and
Blink fame, provided the review of Wages of Wins for the New Yorker.
One of the main stats used is something called a player's "Win Score"
which attempts to measure the complete player, not just points,
rebounds and assists.
Win
Score (WS) = PTS + REB + STL + ½*BLK + ½*AST – FGA – ½*FTA – TO –
½*PF. (Points, Rebounds, Steals, Blocked Shots, Assists, Field Goal
Attempts, Free Throw Attempts, Turnovers, Personal Fouls)
WS is then adjusted for minutes played with the stat, WS48. Of course,
different player positions will have different responsibilities, so to
compare players of different positions the Position Adjusted Win Score
per 48 minutes or PAWS48 is calculated as: WS48 – Average WS48 at
primary position played. This allows an apples to apples comparison
between players at a position, and a reasonable comparison of players
value across positions. Berri's latest article looks at the fascination with Michael Beasley and some early comparisons in the Orlando Summer League.
Will
these statistics-based approaches to player evaluation be accepted by
the "establishment"? Judging by the growing number of young,
MBA-educated GMs in sports, there is a movement towards more efficient
and objective selection criteria. Just as we saw in previous evidence-based coaching articles , the evidence-based general manager is here to stay.
Sports Are 80 Percent Mental
Two
Euro 2008 games and two questionable offsides calls against Italy, one
on defense, the other on offense, are still being talked about this
weekend. First, in the Netherlands opener,
van Nistelrooy scores from an obvious offsides position... except for
Panucci, who is lying on the ground next to the goal. In fact, UEFA had
to defend their referee
for a correct interpretation. The call that did not get an explanation
was Luca Toni's offsides on a cross from Zambrotta in the Romania match, which disallowed a first half goal. The first call was deemed correct, the second one was a blatant error.
Calling
offsides correctly is one of the most difficult officiating duties in
sports. In fact, some have argued that it is nearly impossible given the
limitations of the human eye and the number of objects that need to be
tracked by one assistant referee. Back in 2004, Francisco Belda
Maruenda, M.D. of Centro de Salud de Alquerías in Murcia, Spain, took a
look at the eye movements necessary along with their associated
durations to determine if it was a humanly possible task. Let's look at
his logic.
First, some eye physiology definitions are needed:
Saccadic
movements - when we shift our eyes' focus from one object to another,
we are making a saccadic movement. As an assistant referee (AR) looks
from the ball carrier to the last defender to the offensive players, he
needs to make several saccadic movements to take in the whole scene.
Vergence
movements - there are two types, convergence (changing gaze from
objects far away to objects closer to you), and divergence (just the
opposite, near to far).
Accomodation - to change the focus of the eye from far to near or near to far, the convexity of the retina lens needs to change.
All
of these eye movements, saccadic, vergence and accomodations take time
to accomplish. Let's see how Maruenda added these up for an offsides
call:
- the AR needs to keep track of at least four objects, the
ball, the last two defenders and the offensive receiver of the pass.
There may also be more offensive players to track as well.
- to make
saccadic movements from the first object to each of the remaining
objects will take about 130ms for the first object and then another
10ms per object after that. With four objects to track, that would be a
total of about 160ms.
- if some of the players are on the far side
of the field and some on the near side, then a vergence movement and an
accomodation would be required, taking an additional 360ms for the
accomodation and 640ms for the far to near vergence movement.
- of
course, the players are constantly moving during the play, so their
position is changing rapidly. If the speed of an offensive player is
assumed to be 7.14 m/s, then in 100ms, they will have moved 71cm. This
movement could be the difference between an onside position and an
offside position. See the diagrams below (taken directly from the
article)
Top: No offside, players in correct position.
Bottom: 100 ms later (players' velocity 7.14 m/s), offsides
The
conclusion then, is that the total time needed for the AR to focus on
at least four different objects in sequential order and process their
positions cognitively is beyond the 100ms that would be needed for an
offensive player to move from an onside position when the ball is
played to a perceived offsides position when the AR finally focuses on
him.
There have been some responses to Maruenda's logic, mainly
centered on the fact that ARs have long known they can't watch the ball
and the last defender, so they instead listen for the sound of the ball
being struck while staying focused on the line of defense. This method
may be used, but the sound of the crowd, the muted sound of the boot on
the ball and the slower speed of sound may also have an effect on this
judgement.
There is technology being developed to make offsides
calls with multiple cameras, etc., but FIFA is not in favor of taking
the flag away from the AR yet, just as they are against obvious goal
line technology to watch for goals. It appears the debates and
arguments will live on for the near future.
Source: Belda Maruenda, F. (2004). Can the human eye detect an offside position during a football match?. BMJ, 329(7480), 1470-1472. DOI: 10.1136/bmj.329.7480.1470
Sports Are 80 Percent Mental
Back in April, 80 teams of researchers from 15 countries got together to compete in the 2008 RoboCup German Open,
a soccer tournament where the "athletes" are all totally autonomous
robots like the one pictured above. Four players and a goalkeeper per
team play on a 20x14 meter field and are independent of any human
remote control. They need to have sub-systems that "see" the field,
opponents and the goal; have locomotion logic to move forward, sideways
and back; some tactical logic to sense an opponent and avoid "it"; and
targeting to kick the ball in the direction of the goal. You can see
some brief clips of the robots on the pitch here.
Try the second video to see the most game highlights. The discussion is
in German, if any of you speak it, but the game clips are what to focus
on. The more practical future applications of these sub-systems is to
program robots to do more meaningful tasks like search and rescue
operations in dangerous areas, (fire, earthquake, enemy zones), using
the same visual, locomotion, search algorithms that guide the robot on
the soccer field. In fact, there is a RoboRescue competition as well.
What
struck me most about watching these robots was the complexity of the
logic that needs to be programmed. The visual system that must learn
the field, the sidelines, the dimensions of the goal, the difference
between a teammate and an opponent. The tactical system that must be
"goal" directed, (pun intended). It must learn that the object of the
game is to put the ball into the opponent's goal and stop the ball from
entering your own goal. The constant motion sensor to understand where
they are on the field, when to dribble, when to stop, when to aim and
when to kick. The researchers/programmers in this competition are some
of the brightest minds in the world, yet when you watch the video, you
might have the same reaction that I did; that this is an impressive
start, but they still look rather rudimentary.
Thinking about
the topics we cover here, we often take for granted all of the logic
and skills that human athletes demonstrate every day. I'm thinking
especially of our kids that can easily surpass the performance of these
robots, even as young as 3 years old. My fascination, and probably
these researchers, is HOW we are able to do these tasks so easily. If
we understand more about the "how", then we can also design better
practice environments to advance those skills even faster.
Source: Fraunhofer-Gesellschaft (2008, April 4). Soccer Robots Compete For The Title. ScienceDaily. Retrieved May 29, 2008, from http://www.sciencedaily.com/releases/2008/04/080401110128.htm#
Sports Are 80 Percent Mental
Whether you bend it like Beckham or Ronaldo or Juninho or even
Nakamura; the curving free kick is one of the most exciting plays in
soccer/football. Starting with Rivelino in the 1970 World Cup and on to
the specialists of today, more players know how to do it and understand
the basic physics behind it, but very few can perfect it. But, when it
does happen, by chance or skill, it is the highlight of the game.
But
let's take a look at this from the other side, through the eyes of the
goalkeeper. Obviously, its their job to anticipate where the free kick
is going and get to the spot before the ball crosses the line. He sets
up his wall to, hopefully, narrow the width of the target, but he knows
some players are capable of bending the ball around or over the wall
towards the near post. If you watch highlights of free kick goals, you
often see keepers flat-footed, just watching the ball go into the top
corner. Did they guess wrong and then were not able to react? Did they
guess right but misjudged the flight trajectory of the ball. How much
did the sidespin or "bend" affect their perception of the exact spot
where the ball will cross the line?
Researchers at Queen's University Belfast and the University of the Mediterranean in France tried to figure this out in
this paper.
They wanted to compare the abilities of expert field players and expert
goalkeepers to accurately predict if a free kick would result in an
on-target goal or off-target non-goal. First, a bit about why the ball
"bends". We can thank what's called the "Magnus Force" named after the
19th-century German physicist Gustav Magnus. As seen in the diagram
below, as the ball spins counter clockwise (for a right-footed player
using his instep and kicking the ball on the right side), the air
pressure on the left side of the ball is lower as the spin is in the
same direction as the oncoming air flow. On the right side of the ball,
the spin is in the opposite direction of the air flow, building higher
pressure. The ball will follow the path of least resistance, or
pressure, and "bend" or curve from right to left. The speed of the spin
and the velocity of the shot will determine the amount of bend. For a
clockwise spin, the ball bends from left to right.
The
researchers showed the players three different types of simulated
kicks, a kick bent to the right, a kick bent to the left and a kick
with no spin at all. They showed the players these simulations with
virtual reality headsets and computer controlled "kicks" and "balls"
which they could vary in flight with different programming. The balls
would disappear from view at distances of 10 and 12.5 meters from the
goal. The reasoning is that this cutoff would correspond with the
deadline for reaction time to make a save on the ball. In other words,
if the keeper does not correctly guess the final trajectory and
position of the ball by this point, he most likely will not be able to
physically get to the ball and make the save.
The results showed
that both the players and the keepers, (all 20 were expert players from
elite clubs like AC Milan, Marseille, Bayer LeverkusenSchalke 04), were
able to correctly predict the result of the kicks with no spin added.
However, as 600 RPM spin, either clockwise or counter-clockwise, was
added to the ball, the players success declined significantly.
Interestingly, the keepers did no better, statistically, then the field
players. The researchers conclusion was that the players used the
"current heading direction" of the ball to predict the final result,
rather than factoring the future affect of the acceleration and change
in trajectory caused by the spin.
Game Highlights
Just as we saw in the
Baseball Hitting post,
our human perception skill in tracking flying objects, especially those
that are spinning and changing direction, are not perfect. If we
understand the physics of the spinning ball and we can better guess at
its path, but the pitcher or the free kick taker doesn't usually offer
this information beforehand! In the next few posts, I'll be looking at
a related topic in perception; a concept known as "Quiet Eye",
developed by
Prof. Joan Vickers. Check back as this is one of the best applications of cognitive science in sports that I have seen.
