When Milwaukee Brewers pitcher Chris Capuano reports for spring
training in April, he will be anxious to demonstrate the effects of a
performance-enhancing off-season.
His brain will benefit from a sharper focus, while his throwing arm will boast an extra boost that has been missing since 2006.
Stimulants? Steroids? Scandal?
No. Capuano just had LASIK surgery for his eyes and "Tommy John"
surgery for his injured elbow. And if he chooses, he could have a few cups of coffee
before the game. Of course, were he to choose amphetamines to improve
his focus or steroids to increase his strength, he would be banned and
berated.
Society decides
There is confusion over the means and methods athletes have available to enhance their performance.
Certainly, corrective eye surgery to raise your vision level to 20/20
seems fair, but many athletes go into the procedure hoping to come out
with enhanced 20/15 or 20/10 eyesight.
Replacing a damaged elbow ligament with a tendon doesn't seem like
cheating, but what if it's done on a healthy elbow hoping for a few more
miles per hour on a fastball that has faded over the years?
In December of last year, a commentary in the journal Nature recommended a fresh look at cognitive-enhancing drugs
and where to draw the line in the sand between natural performance and
enhanced performance. The authors, an esteemed group of neuroscientists
and ethicists, argued that "enhanced" is only defined by the rules set
by society.
Abuse of prescription drugs, such as Ritalin and Adderall, is
illegal because of the potential, harmful side effects. Still, reports
of the rising use of these drugs by college students and professionals
show the demand for options beyond nutrition, exercise and sleep.
These drugs are just the first generation of possible brain boosting supplements, which is why the Nature
commentators are calling for an organized, stigma-free approach to
evaluating the risks, benefits and ethics of future products.
Even in Major League Baseball, there is mounting evidence that
cognitive-enhancing drugs may be on the rise. Since MLB banned
amphetamines in 2006, there has been a dramatic rise in the number of
therapeutic use exemptions issued to players for attention-deficit disorder
diagnoses, for which drugs like Ritalin and Adderall can be
legitimately prescribed. In 2006, 28 players applied for the exemption,
while a year later there were 103. There is suspicion that many of
these ADD diagnoses are just excuses to get the pills.
Legal jolt
So, what if there was a cognitive-enhancing, sports supplement that
increased alertness, concentration, reaction time and focus while also
decreasing the perception of muscle fatigue? Even more encouraging,
this supplement is sold in millions of outlets and is socially accepted
worldwide. It comes in three sizes, tall, grande or venti — coffee.
More specifically, caffeine has been the subject of many recent studies of its effectiveness, both cognitively and physiologically.
Earlier this year, Dr. Carrie Ruxton completed a literature survey
to summarize 41 double-blind, placebo-controlled trials published over
the past 15 years to establish what range of caffeine consumption would
maximize benefits and minimize risk for cognitive function, mood,
physical performance and hydration. The studies were divided into two
categories, those that looked at the cognitive effects and those that
looked at physical performance effects.
The results concluded that there was a significant improvement in
cognitive functions like attention, reaction time and mental processing
as well as physical benefits described as increased "time to
exhaustion" and decreased "perception of fatigue" in cycling and
running tests.
Given these results, how exactly does caffeine perform these
wonderful tricks? Dr. Ruxton explains: "Caffeine is believed to impact
on mood and performance by inhibiting the binding of both adenosine and
benzodiazepine receptor ligands to brain membranes. As these
neurotransmitters are known to slow down brain activity, a blockade of
their receptors lessens this effect."
Bottom line, the chemicals in your brain that would cause you to
feel tired are blocked, giving you a feeling of ongoing alertness. This
pharmacological process is very similar to that of the ADD drugs.
Ban coffee?
If caffeine is such a clear-cut performance enhancing supplement,
why did the World Anti-Doping Agency (WADA) first add caffeine to its
banned substance list, only to remove it in 2004? At the time that it
was placed on the banned list, the threshold for a positive caffeine
test was set to a post-exercise urinary caffeine concentration of about three to four cups of strong coffee.
However, more recent research has shown that caffeine has ergogenic
effects at levels as low as the equivalent of one to two cups of coffee. So,
it was hard for WADA to know where to draw the line between athletes
just having a few morning cups of coffee/tea and those that were
intentionally consuming caffeine to increase their performance level.
If Chris Capuano has a double espresso before pitching, his brain,
eyes and arm should enhance his performance in the game. Is that an
unfair advantage? Science will continue to offer new and improved
methods for raising an athlete's game above the competition. Players,
league officials and fans will have to decide where to draw the line.
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.
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."
When
it comes to improving your golf game, you can spend thousands of
dollars buying the latest titanium-induced, Tiger-promoted golf clubs;
taking private lessons from the local "I used to be on the Tour" pro;
or trying every slice-correcting, swing-speed-estimating,
GPS-distance-guessing gadget. But, in the end, it’s about getting that
little white sphere to go where you intended it to go. Don't worry,
there are many very smart people trying to help you by designing the
ultimate golf ball. Of course, they are also after a slice of this
billion dollar industry, as any technological advancement that can grab
a few more market share points is worth the investment.
In
fact, the golf ball wars can get nasty. Earlier this month, Callaway
Golf won a court order permanently halting sales of the industry's
leading ball, Titleist's Pro V1, arguing patent infringements involving
its solid core technology which Callaway acquired when it bought
Spaulding/Top Flite in 2003. Titleist disagrees with the decision and
will appeal, but in the meantime has altered its manufacturing process
so that the patents in question are not used.
The
challenge for golf ball manufacturers is to design a better performing
ball within the constraints set by United States Golf Association. The
USGA enforces limits on the size, weight and initial performance
characteristics in an attempt to keep the playing field somewhat level.
Every "sanctioned" golf ball must weigh less than 1.62 ounces with a
diameter smaller than 1.68 inches. It also must have a similar initial
velocity when hit with a metal striker, and rebound at the same angle
and speed when hit against a metal block. So, what is left to tinker
with? Manufacturers have focused on the internal materials in the ball
and its cover design.
Today's
balls have 2, 3 or 4 layers of different internal polymer materials to
be able to respond differently when hit with a driver versus, say, a
wedge. When hit with a driver at much higher swing speed, the energy
transfer goes all the way to the core by compressing ball, reducing
backspin. During a slower swing with a club that has more angle loft,
the energy stays closer to the surface of the ball and allows the
grooves of the club to grab onto the ball's cover producing more spin.
When driving the ball off of the tee, the preference is more distance
and less loft, so a lower backspin is required. For closer shots, more
backspin and control are needed.
The Science of Dimples
Which
brings us to the cover of the ball and all of the design possibilities.
Two forces affect the flight and distance of flying spheres, gravity
and aerodynamics. Eventually, gravity wins once the momentum of the
ball is slowed by the aerodynamic drag. Since all golf clubs have some
angular loft to their clubface, the struck ball will have backspin. As
explained by the Magnus Force effect, the air pressure will be lower on
the top of the ball since that side is moving slower relative to the
air around it. This creates lift as the ball will go in the direction
of the lower air pressure. Counteracting this lift is the friction or
drag the ball experiences while flying through the air.
Think about a boat moving through
water. At the front of the boat, the water moves smoothly around the
sides of the boat, but eventually separates from the boat on the back
side. This leaves behind a turbulent wake where the water is agitated
and creates a lower pressure area. The larger the wake, the more drag
is created. A ball in flight has the same properties.
The
secret then is how to reduce this wake behind the ball. Enter the
infamous golf ball dimples. Dimples on a golf ball create a thin
turbulent boundary layer of air molecules that sticks to the ball's
contour longer than on a smooth ball. This allows the flowing air to
follow the ball's surface farther around the back of the ball, which
decreases the size of the wake. In fact, research has shown that a
dimpled ball travels about twice as far as a smooth ball.
So,
the design competition comes down to perfecting the dimple, since not
all dimples are created equal! The number, size and shape can have a
dramatic impact on performance. Typically, today's balls have 300-500
spherically shaped dimples, each with a depth of about .010 inch.
However, varying just the depth by .001 inch can have dramatic effects
on the ball's flight.
Regarding shape, these traditional round dimple patterns cover up to 86
percent of the surface of the golf ball. To create better coverage,
Callaway Golf's HX ball uses hexagon shaped dimples that can create a
denser lattice of dimples leaving fewer flat spots. Creating just the
right design has traditionally been a trial-and-error process of
creating a prototype then testing in a wind tunnel. This time-consuming
process does not allow for the extreme fine-tuning of the variables.
Simulation Solution
At
the 61st Meeting of the American Physical Society's Division of Fluid
Dynamics last month in San Antonio, a team of researchers from Arizona
State University and the University of Maryland is reporting new
findings that may soon give golf ball manufacturers a more efficient
method of testing their designs. Their research takes a different
approach, using mathematical equations that model the physics of a golf
ball in flight. ASU's Clinton Smith, a Ph.D. student and his advisor
Kyle Squires collaborated with Nikolaos Beratlis and Elias Balaras at
the University of Maryland and Masaya Tsunoda of Sumitomo Rubber
Industries, Ltd. The team has been developing highly efficient
algorithms and software to solve these equations on parallel
supercomputers, which can reduce the simulation time from years to
hours.
Now
that the model and process is in place, the next step is to begin the
quest for the ultimate dimple. In the meantime, when someone asks you,
"What's your handicap?" you can confidently tell them, "Well, my golf
ball's design does not optimize its drag coefficient which results in a
lower loft and spin rate from its poor aerodynamics."
The loneliest men in sports have not been making any friends lately.
Both
umpires and referees have been making news, despite their often
repeated goal, stated by World Series rookie umpire Tom Hallion said after Game 3: “As an umpire, you never want to be involved
in the outcome of the game.” He added: “We like to get every play
right. We’re human beings, and sometimes we get them wrong.”
Hallion and his five partners at October's Fall Classic did not quite reach their goal. In
Game 3, Hallion called Carl Crawford safe at first on a close play, but
replays showed he was out. In Game 4, it was the Phillies who benefited
after veteran umpire, Tim Welke, called Jimmy Rollins safe at third
during a rundown, despite an obvious tag on his backside.
The men in stripes are not doing any better. Veteran NFL referee, Ed Hoculi (aka "Guns"), blew a call in Week 2's Broncos/Chargers game.
Broncos' quarterback Jay Cutler let the ball slip out of his hand and
the Chargers recovered. However, Hoculi ruled the play an incomplete
pass. The video replay booth called it a fumble, but since Hoculi had
blown his whistle, the call could not be reversed.
Not
to be outdone by their American counterparts, two English soccer
officials have set a new standard for head-scratching calls.
In a Sept. 22 game between Watford and Reading,
referee Stuart Atwell and one of his linesmen, Nigel Bannister,
combined to become the ultimate sales pitch for any type of goal-line
replay technology. After a scramble in front of goal, the ball bounced
across the end line, two yards wide of the nearest goalpost. As both
teams headed up the field and Watford prepared for a goal kick,
Bannister signaled to Atwell that he saw the ball cross the line
between the goalposts and that Reading should be awarded a goal. To the
astonishment of all 22 players on the field and the 14,761 fans, Atwell
overruled his own eyes and gave the goal to Reading. The replay made it
painfully obvious how wrong the call was:
So, assuming officials want some kind of automated technical assistance, what is available?
First,
pure video instant replay gives officials a second, slower chance to
see the play again and possibly adjust their live call. All four major
sports leagues in the United States use replay at some level.
In
addition to judging if a shot was taken before the buzzer, the NBA
added replay this season to differentiate 2-point versus 3-point
baskets. MLB commissioner Bud Selig has put a stop to the spread of
replay beyond the home run/foul ball call for now, but public pressure
may change that. The NHL’s use of replay focuses mainly on different
goal scoring scenarios. The NFL is the most advanced user of replay to
judge multiple situations.
Second,
an emerging selection of decision-support tools can make the actual
call for the officials using location-based technology. In tennis, the Hawk-Eye system is being used at such high-profile events as Wimbledon and the U.S. Open.
A
system of six high-speed cameras records a ball's movement, which is
useful when it bounces near one of the court lines. It feeds the
cameras' input to a central computer that analyzes the data from all
angles and then creates a motion graphic that simulates the ball's
location when it bounces on the court, either on the line or next to
the line, with a judgment of "in" or "out."
A
player can challenge a line umpire's original call, but Hawk-Eye's
ruling is then final. The interesting illusion that tennis fans have
accepted is watching this 3D simulation as if it is based on a single
camera’s footage of the ball. Actually, the sequence shown to viewers
is Hawk-Eye's best estimate as to what actually happened based on the
data it received from the cameras. There have been more than 550
challenges at the U.S. Open since 2006 when Hawk-Eye was installed.
Thirty percent of those challenges resulted in a call being reversed.
In soccer, Adidas and Cairos Technologies
have partnered to create an "intelligent" ball that includes a
microchip that transmits its location on the field to a computer.
The
system also places a thin, underground electrical wire that surrounds
each goal. If the ball's location is sensed to be completely inside the
boundary of the goal, a signal is sent to a watch worn by the referee
indicating that a goal has been scored.
This
technology would have saved Atwell and Bannister from their
embarrassment. However, after extensive testing at several FIFA
tournaments, Sepp Blatter, president of FIFA, announced in March that
instead of technology, two additional human referee assistants would be
used to judge whether a goal was scored. "Let it be as it is and let's
leave it (soccer) with errors," Blatter said. "The television companies
will have the right to say he (the referee) was right or wrong, but
still the referee makes the decision — a man, not a machine."
Interestingly, the English Premier League was also testing the use of
Hawk-Eye as an alternative to Adidas' smart ball.
Even if the umps and refs don't want to use the technology, sports television producers still want to empower the fans.
In
baseball, ESPN's "K-zone" and Fox Sports' "Fox Trax" show a virtual
representation of pitches and the strike zone to let us judge the
accuracy of the home-plate umpire's calls. Think that last called
strike was a bit outside? Watch the computer generated replay that is
accurate to within one-half inch.
Then, go ahead and yell at the ump. If only they could come up with a way to transmit our voices directly into the stadium.
A
player can feel it during a game when they hit a match-winning goal
or when they miss a wide open net. A team can feel it when they come
back from a deficit late in the game or when their lead in the league vanishes. A fan can feel it as their team "catches fire" or goes "as
cold as ice". And, play-by-play announcers love to talk about it. We
know it as the "Big Mo", the "Hot Hand", and being "In The Zone" while
the psychologists call it Psychological Momentum. But, does it really
exist? Is it just a temporary shift in confidence and mood or does it
actually change the outcome of a game or a season? As expected, there
are lots of opinions available.
The Oxford Dictionary of Sports Science defines psychological momentum as, "the
positive or negative change in cognition, affect, physiology, and
behavior caused by an event or series of events that affects either the
perceptions of the competitors or, perhaps, the quality of performance
and the outcome of the competition. Positive momentum is associated
with periods of competition, such as a winning streak, in which
everything seems to ‘go right’ for the competitors. In contrast,
negative momentum is associated with periods, such as a losing streak,
when everything seems to ‘go wrong’." The interesting phrase in
this definition is that Psychological Momentum (PM) "affects either the
perceptions of the competitors or, perhaps, the quality
of performance and the outcome of the competition." Most of the
analyses on PM focus on the quantitative side to try to prove or
disprove PM's affect on individual stats or team wins and losses.
Regarding PM in baseball, a Wall St. Journal article
looked at last year's MLB playoffs, only to conclude there was no
affect on postseason play coming from team momentum at the end of the
regular season. More recently, Another Cubs Blog
also looked at momentum into this year's playoffs including opinion
from baseball stats guru, Bill James, another PM buster. For
basketball, Thomas Gilovich's 1985 research
into streaky, "hot hand" NBA shooting is the foundation for most of
today's arguments against the existence of PM, or at least its affect
on outcomes.
This view that if we can't see it in the numbers, more than would be
expected, then PM does not exist may not capture the whole picture. Lee
Crust and Mark Nesti have recommended that researchers look at psychological momentum more from the qualitative side.
Maybe there are more subjective measures of athlete or team confidence
that contribute to success that don't show up in individual stats or
account for teams wins and losses. As Jeff Greenwaldput it in his article, Riding the Wave of Momentum, "The
reason momentum is so powerful is because of the heightened sense of
confidence it gives us -- the most important aspect of peak
performance. There is a term in sport psychology known as
self-efficacy, which is simply a player's belief in his/her ability to
perform a specific task or shot. Typically, a player’s success depends
on this efficacy. During a momentum shift, self-efficacy is very high
and players have immediate proof their ability matches the challenge.
As stated earlier, they then experience subsequent increases in energy
and motivation, and gain a feeling of control. In addition, during a
positive momentum shift, a player’s self-image also changes. He/she
feels invincible and this takes the "performer self" to a higher level."
There would seem to be three distinct areas of focus for PM; an
individual's performance within a game, a team's performance within a
game and a team's performance across a series of games. So, what are
the relationships between these three scenarios? Does one player's
scoring streak or key play lift the team's PM, or does a close,
hard-fought team win rally the players' morale and confidence for the
next game? Seeing the need for a conceptual framework to cover all of
these bases, Jim Taylor and Andrew Demick created their Multidimensional Model of Momentum in Sports, which is still the most widely cited model for PM. Their definition of PM, "a
positive or negative change in cognition, affect, physiology, and
behavior caused by an event or series of events that will result in a
commensurate shift in performance and competitive outcome", leads to the six key elements to what they call the "momentum chain".
First, momentum shifts begin with a "precipitating event", like an
interception or fumble recovery in football or a dramatic 3-point shot
in basketball. The effect that this event has on each athlete varies
depending on their own perception of the game situation, their
self-confidence and level of self-efficacy to control the situation.
Second, this event leads to "changes in cognition, physiology, and
affect." Again, depending on the athlete, his or her base confidence
will determine how strongly they react to the events, to the point of
having physiological changes like tightness and panic in negative
situations or a feeling of renewed energy after positive events.
Third, a "change in behavior" would come from all of these internal
perceptions. Coaches and fans would be able to see real changes in the
style of play from the players as they react to the positive or
negative momentum chain.
Fourth, the next logical step after behavior changes is to notice a
"change in performance." Taylor and Demick note that momentum is the
exception not the norm during a game. Without the precipitating event,
there should not be noticeable momentum shifts.
Fifth, for sports with head to head competition, momentum is a two-way
street and needs a "contiguous and opposing change for the opponent."
So, if after a goal, the attacking team celebrates some increased PM,
but the defending team does not experience an equal negative PM, then
the immediate flow of the game should remain the same. Its only when
the balance of momentum shifts from one team to the other. Levels of
experience in athletes has been shown to mitigate the effects of
momentum, as veteran players can handle the ups and downs of a game
better than novices.
Finally, at the end of the chain, if momentum makes it that far, there
should be an immediate outcome change. When the pressure of a
precipitating event occurs against a team, the players may begin to get
out of their normal, confident flow and start to overanalyze their own
performance and skills. We saw this in Dr. Sian Beilock's research in
our article, Putt With Your Brain - Part 2.
As an athlete's skills improve they don't need to consciously focus on
them during a game. But pressure brought on by a negative event can
take them out of this "automatic" mode as they start to focus on their
mechanics to fix or reverse the problem. As Patrick Cohn, a sport psychologist, pointed out in a recent USA Today article on momentum,
"You stop playing the game you played to be in that position. And the
moment you switch to trying not to screw up, you go from a very
offensive mind-set to a very defensive mind-set. If you're focusing too
much on the outcome, it's difficult to play freely. And now they're
worried more about the consequences and what's going to happen than
what they need to do right now."
There
is no doubt that we will continue to hear references to momentum swings
during games. When you do, you can conduct your own mini experiment and
watch the reactions of the players and the teams over the next section
of the game to see if that "precipitating event" actually leads to a
game-changing moment.
Jim Taylor, Andrew Demick (1994). A multidimensional model of momentum in sports Journal of Applied Sport Psychology, 6 (1), 51-70 DOI: 10.1080/10413209408406465
If there is a poster child sport for our favorite phrase, "Sports Are 80 Percent Mental",
it must be golf. Maybe its the slow pace of play that gives us plenty
of time to think between shots. Maybe its the "on stage" performance
feeling we get when we step up to that first tee in front of our
friends (or strangers!) Maybe its the "high" of an amazing approach
shot that lands 3 feet from the cup followed by the "low" of missing
the birdie putt.
From any angle, a golf course is the sport
psychologist's laboratory to study the mix of emotions, confidence,
skill execution and internal cognitive processes that are needed to
avoid buying rounds at the 19th hole. Last time, we looked at some of
the recent research on putting mechanics, but, as promised, we now turn to the mental side of putting.
An underlying theme to this work is the concept of automaticity,
or the ability to carry out sport skills without consciously thinking
about them. Performing below expectations (i.e. choking) starts when we
allow our minds to step out of this automatic mode and start thinking
about the steps to our putting stroke and all of those "swing thoughts"
that come with it ("keep your elbows in", "head down", "straight
back").
Our brain over analyzes and second-guesses the motor skills we
have learned from hundreds of practice putts. Previously, we looked at automaticity in other sports.
Of course, a key distinction to the definition of choking is that you
are playing "well below expectations". If you normally shoot par, but
now start missing easy putts, then there may be distractions that are
taking you out of your normal flow. Choking implies a temporary and
abnormal event. Automaticity theory would claim that it is these
distractions from some perceived pressure to perform that are affecting
your game.
Most research into sport skill performance divides the world into two
groups, novices and experts. Most sports have their own measures of
where the dividing line is between these groups. Expertise would imply
performance results not just experience. So, a golfer who has been
hacking away for 20 years but still can't break 100 would still be put
in the "novice" category.
Sport scientists design experiments that
compare performance between the groups given some variables, and then
hypothesize on the reason for the observed differences. Beilock, et al
have looked at golf putting from several different angles over the
years. Their research builds on itself, so let's review in reverse
chronological order.
Back in 2001, they began by comparing the two competing theories
of choking, distraction theory vs. explicit monitoring theory, and
designed a putting experiment to find the better explanation.
Distraction theory explains choking by assuming that the task of
putting requires your direct attention and that high pressure
situations will cause you to perform dual tasks - focus on your putting
but also think about the pressure. This theory assumes there is no
automaticity in skill learning and that we have to focus our attention
on the skill every time.
Explicit monitoring theory claims that over
time, as we practice a skill to the point of becoming an "expert", we
proceduralize the task so that it becomes "automatic". Then, during a
high pressure situation, our brain becomes so concerned about
performance that it takes us out of automatic mode and tries to focus
on each step of the task. The research supported the explicit
monitoring theory as it was shown that the golf putting task was
affected by distractions and pressure for the experts but not the
novice putters.
So, how do we block out the pressure, so that our automaticity can kick in? Another 2001 study by Beilock
looked at mental imagery during putting. Using the same explicit
monitoring theory, should we try to think positive thoughts, like "this
ball is going in the hole" or "I have made this putt many times"? Also,
what happens if a stray negative thought, "don't miss this one!" enters
our brain? Should we try to suppress it and replace it with happy
self-talk?
She set up four groups, one receiving positive comments, one
receiving negative comments, one receiving negative comments followed
by positive comments and one receiving none as a control group. As
expected, the happy people did improve their putting over the course of
the trials, while the negative imagery hurt performance.
But, the
negative replaced with positive thought group did not show any more
improvement over the control group. So, when faced with a high
pressure, stressful situation ripe with the possibilities of choking,
try to repeat positive thoughts, but don't worry too much if the
occasional doubt creeps in.
Our strategy towards putting should also vary depending on our current
skill level. While learning the intricacies of putting, novices should
use different methods than experts, according to a 2004 study by Beilock, et al.
Novice golfers need to pay attention to the step by step components of
their swing, and they perform better when they do focus on the
declarative knowledge required.
Expert golfers, however, have practiced
their swing or putt so often that it has become "second nature" to the
point that if they are told to focus on the individual components of
their swing, they perform poorly. The experiment asked both novices and
expert golfers to first focus on their actual putting stroke by saying
the word "straight" when hitting the ball and to notice the alignment
of the putter face with the ball.
Next, they were asked to putt while
also listening for a certain tone played in the background. When they
heard the tone they were to call it out while putting. The first
scenario, known as "skill-focused", caused the novices to putt more
accurately but the experts to struggle. The second scenario, called
"dual-task", distracted the novices enough to affect their putts, while
the experts were not bothered and their putting accuracy was better.
Beilock showed that novices need the task focus to succeed while they
are learning to putt, while experts have internalized the putting
stroke so that even when asked to do two things, the putting stroke can
be put on "auto-pilot".
Finally, in 2008, Beilock's team added one more twist
to this debate. Does a stress factor even affect a golfer's performance
in their mind before they putt? This time, golfers, divided into the
usual novice and expert groups, were asked to first imagine or "image
execute" themselves making a putt followed by an actual putt. The
stress factor was to perform one trial under a normal, "take all the
time you need" time scenario and then another under a speeded or
time-limited scenario.
The novices performed better under the
non-hurried scenario in imagining the putt first followed by the actual
putt. The experts, however, actually did better in the hurried scenario
and worse in the relaxed setting. Again, the automaticity factor
explains the differences between the groups.
The bottom line throughout all of these studies is that if you're
learning to play golf, which includes putting, you should focus on your
swing/stroke but beware of the distractions which will take away your
concentration. That seems pretty logical, but for those that normally
putt very well, if you feel stress to sink that birdie putt, don't try
to focus in on the mechanics of your stroke. Trust the years of
experience that has taught your brain the combination of sensorimotor
skills of putting.
Just remember the Chevy Chase/Ty Webb philosophy;
"I'm going to give you a little advice. There's a force in the universe
that makes things happen. And all you have to do is get in touch with
it, stop thinking, let things happen, and be the ball.... Nah-na-na-na,
Ma-na-na-na...."
Sian L. Beilock, Thomas H. Carr (2001). On the fragility of skilled performance: What governs choking under pressure? Journal of Experimental Psychology: General, 130 (4), 701-725 DOI: 10.1037//0096-3445.130.4.701
Sian
L. Beilock; James A. Afremow; Amy L. Rabe; Thomas H. Carr (2001).
"Don't Miss!" The Debilitating Effects of Suppressive Imagery on Golf
Putting Performance Journal of Sport and Exercise Psychology, 23 (3)
Beilock
S.L.; Bertenthal B.I.; McCoy A.M.; Carr T.H. (2004). Haste does not
always make waste: Expertise, direction of attention, and speed versus
accuracy in performing sensorimotor skills Psychonomic Bulletin & Review, 11 (2), 373-379
Sian
Beilock, Sara Gonso (2008). Putting in the mind versus putting on the
green: Expertise, performance time, and the linking of imagery and
action The Quarterly Journal of Experimental Psychology, 61 (6), 920-932 DOI: 10.1080/17470210701625626
If
Mark Twain thinks golf is "a good walk spoiled", then putting must be a
brief pause to make you reconsider ever walking again. With about 50%
of our score being determined on the green, we are constantly in search
of the "secret" to getting the little white ball to disappear into the
cup.
Lucky for us, there is no shortage of really smart people also
looking for the answer. The first 8 months of 2008 have been no
exception, with a golf cart full of research papers on just the topic
of putting.
Is the secret in the mechanics of the putt stroke or maybe
the cognitive set-up to the putt or even the golfer's psyche when
stepping up to the ball? This first post will focus on the mechanical
side and then we'll follow-up next time with a look inside the golfer's
mind.
Let's start with a tip that most golf instructors would give, "Keep
your head still when you putt". Jack Nicklaus said it in 1974, "the
premier technical cause of missed putts is head movement" (from "Golf My Way") and Tiger Woods said it in 2001, "Every good putter keeps the head absolutely still from start to finish" (from "How I Play Golf").
Who would argue with the two greatest golfers of all time? His name is Professor Timothy Lee,
from McMaster University, and he wanted to test that observation. So,
he gathered two groups of golfers, amateurs with handicaps of 12-40,
and professionals with scratch handicaps. Using an infrared tracking
system, his team tracked the motion of the putter head and the golfer's
head during sixty putts.
As predicted, the amateurs' head moved back in unison with their putter
head, something Lee calls an "allocentric" movement, which agrees with
the advice that novice golfers move their head. However, the expert
golfers did not keep their head still, but rather moved their heads
slightly in the opposite direction of the putter head.
On the
backswing, the golfer's head moved slightly forward; on the forward
stroke, the head moved slightly backward. This "egocentric" movement
may be the more natural response to maintain a centered, balanced
stance throughout the stroke. "The exact reasons for the opposite
coordination patterns are not entirely clear," explains Lee. "However,
we suspect that the duffers tend to just sway their body with the
motions of the putter.
In contrast, the good golfers probably are
trying to maintain a stable, central body position by counteracting the
destabilization caused by the putter backswing with a forward motion of
the head. The direction of head motion is then reversed when the putter
moves forward to strike the ball." Does that mean that pro golfers like
Tiger are not keeping their heads still? No, just that you may not have to keep your head perfectly still to putt effectively.
So, what if you do have the bad habit of moving your head? Just teach
yourself to change your putting motion and you will be cutting strokes
off of your score, right? Well, not so fast. Simon Jenkins of Leeds Metropolitan University tested 15
members of the PGA European Tour to see if they could break old
physical habits during putting. His team found that players who usually
use shoulder movement in their putting action were not able to change
their ways even when instructed to use a different motion. Old habits
die hard.
Let's say you do keep your head still (nice job!), but you still 3-putt
most greens? What's the next step on the road to birdie putts? Of the
three main components of a putt, (angle of the face of the putter head
on contact, putting stroke path and the impact point on the putter),
which has the greatest effect on success?
Back in February, Jon Karlsen of the Norwegian School of Sport Sciences
in Oslo, asked 71 elite golfers (mean handicap of 1.8) to make a total
of 1301 putts (why not just 1300?) from about 12 feet to find out. His
results showed that face angle was the most important (80%), followed
by putter path (17%) and impact point (3%).
OK, forget the moving head thing and work on your putter blade angle at
contact and you will be taking honors at every tee. Wait, Jon Karlsen
came back in July with an update.
This time he compared green reading, putting technique and green
surface inconsistencies to see which of those variables we should
discuss with our golf pro. Forty-three expert golfers putted 50 times
from varying distances. Results showed that green reading (60%) was the
most dominant factor for success with technique (34%) and green
inconsistency (6%) trailing significantly.
So, after reading all of this, all you really need is something like the BreakMaster,
which will help you read the breaks and the slope to the hole! Then,
keep the putter blade square to the ball and don't move your head, at
least not in an allocentric way, that is if you can break your bad
habit of doing it. No problem, right? Well, next time we'll talk about
your brain's attitude towards putting and all the ways your putt could
go wrong before you even hit it!
Timothy
D. Lee, Tadao Ishikura, Stefan Kegel, Dave Gonzalez, Steven Passmore
(2008). Head–Putter Coordination Patterns in Expert and Less Skilled
Golfers Journal of Motor Behavior, 40 (4), 267-272 DOI: 10.3200/JMBR.40.4.267-272
Jenkins, Simon (2008). Can Elite Tournament Professional Golfers Prevent Habitual Actions in Their Putting Actions? International Journal of Sports Science & Coaching, 3 (1), 117-127
Jon
Karlsen, Gerald Smith, Johnny Nilsson (2007). The stroke has only a
minor influence on direction consistency in golf putting among elite
players Journal of Sports Sciences, 26 (3), 243-250 DOI: 10.1080/02640410701530902
It
sounds like a sales job from a 12 year old; "Actually, Dad, this is not
just another video game. Its a virtual, scenario-based microcosm of
real world experiences that will enhance my decision-making abilities
and my cognitive perceptions of the challenges of the sport's
environment." You respond with, "So, how much is Madden 09?"
With over 5 million copies of Madden 08 sold, the release of the latest
version two weeks ago is rocketing up the charts. Days and late nights
are being spent all over the world creating rosters, customizing plays
and playing entire seasons, all for pure entertainment purposes. Can
all of those hours spent with controller in hands actually be
beneficial to young athletes? Shouldn't they be outside in the fresh
air and sunshine playing real sports? Well, yes, to both questions.
Playing video games, (aka "gaming"), as a
form of learning has been receiving increased recent attention from
educational psychology researchers. At this month's American
Psychological Association annual convention, several groups of
researchers presented studies of the added benefits of playing video games,
from problem-solving and critical thinking to better scientific
reasoning. In one of the studies by Fordham University psychologist Fran C. Blumberg, PhD,
and Sabrina S. Ismailer, MSED, 122 fifth-, sixth- and seventh-graders'
problem-solving behavior was observed while playing a video game that
they had never seen before. As the children played the game, they were
asked to think aloud for 20 minutes. Researchers assessed their
problem-solving ability by listening to the statements they were making
while playing. The results showed that playing video games can improve cognitive and perceptual skills.
"Younger children seem more interested in setting short-term goals for
their learning in the game compared to older children who are more
interested in simply playing and the actions of playing," said
Blumberg. "Thus, younger children may show a greater need for focusing
on small aspects of a given problem than older children, even in a
leisure-based situation such as playing video games."
Also, in a recent article on video game learning, David Williamson Shaffer, professor of educational psychology at the University of Wisconsin-Madision and author of the book "How Computer Games Help Children Learn",
argues that if a game is realistically based on real-world scenarios
and rules, it can help the child learn. “The question though is,"
Shaffer said, "is what they are doing a good simulation of what is
happening in the real world?" Shaffer explains the research happening
on this topic at his UW lab, named Epistemic Games:
There are some words of caution out there. In a recent article, educational psychologist Jane M. Healy, author of "Failure to Connect: How Computers Affect our Children's Minds and What We Can Do About It," urges educators to proceed carefully. "The
main question is whether the activity, whatever it is, is educationally
valid and contributes significantly to whatever is being studied," she
says. "The point is not whether kids are
'playing' with learning, or what medium they are playing in — a ball
field or a Wii setup or a physics lab or art studio — but rather why
they are doing it. Just because it is electronic does not make it any
better, and it may turn out not to be as valuable."
If we accept that there is some validity
to teaching/learning with video game simulations, how can we move this
to the sports arena? Obviously, there is no substitute for playing the
real game with real players, opponents, pressure, etc., but more teams
and coaches are turning to simulation games for greater efficiency in
the learning process. If the objective is to expose players to plays,
tactics, field vision and critical thinking, then a gaming session can
begin to introduce these concepts that will be validated later on the
field during "real" practice. This homework can also be done at home,
not requiring teammates, fields, equipment, etc. As mentioned in the
videos above, another driving factor in the use of games is to reach
this young, Web 2.0 audience through a medium that they already know,
understand and enjoy. The motivation to learn is inherent with the use
of games. The "don't tell them its good for them" secret is key to
seeing progress with this type of training.
One of the best examples of video game adaptation for sports learning is from XOS Technologies
and their modified version of the Madden NFL game. In 2007, they
licensed the core development engine from EA Sports and created a
football simulation, called SportMotion,
that can be used for individual training. With the familiar Madden
user interface, coaches can first load their playbook into the game, as
well as their opponent's expected plays. Then, the athlete can "play"
the game but will now see their own team's plays being run by the
virtual players. Imagine the difference in learning style for a new
quarterback. Instead of studying static X's and O's on a
two-dimensional piece of paper, they can now watch and then play a
virtual simulation of the same play in motion against a variety of
different defenses. With a "first-person" view of the play unfolding,
they will see the options available in a "real-time" mode which will
force faster reaction and decision-making skills. To take the
simulation one step further, XOS has added a virtual reality option
that takes the game controller out of the player's hands and replaces
it with a VR suit and goggles allowing him to physically play the game,
throw the ball, etc. through his virtual eyes. Take a look at this
promotional video from XOS:
XOS is winning some high praise for its system, including none other than Phillip Fulmer, Head Coach of the University of Tennesee football team.
“We’re leading the nation by taking advantage of this cutting-edge
technology and we couldn’t be more pumped about it,” Fulmer said. “UT
football has a long and storied tradition of success and because we
look to pioneer groundbreaking concepts before anyone else, we’ll
proudly continue that history. The XOS PlayAction Simulator begins a
new chapter for UT and we’re pleased to add it to our football training
regiment.” Albert Tsai, vice president of advanced research at XOS
Technologies, says, “We’ve basically added functionality to popular EA
video games such as customizable playbooks, diagrams and testing
sequences to better prepare athletes for specific opponents.
Additionally, the software includes built-in teaching and reporting
tools so that coaches Fulmer, Cutcliffe and Cooter can analyze and
track the tactical-skill development of the team. At the same time, the
Volunteers can experience immediate benefits because the familiarity
with the EA SPORTS brand requires little to no learning curve for their
players.”
So, the next time your son (or daughter!)
is begging for 10 more minutes on the Xbox to make sure the Packers
destroy the Vikings once again (sorry, a little Wisconsin bias), you
may want to reconsider pulling the plug. Then, send them outside for
that fresh air.
Michael
Phelps, Nastia Liukin, Misty May-Treanor and Lin Dan are four Olympic
athletes who have each spent most of their life learning the skills
needed to reach the top of their respective sports, swimming,
gymnastics, beach volleyball and badminton (you were wondering about
Lin, weren't you...) Their physical skills are obvious and amazing to
watch. For just a few minutes, instead of being a spectator, try to
step inside the heads of each of them and try to imagine what their
brains must accomplish when they are competing and how different the
mental tasks are for each of their sports.
On
a continuum from repetitive motion to reactive motion, these four
sports each require a different level of brain signal to muscle
movement. Think of Phelps finishing off one more gold medal race in
the last 50 meters. His brain has one goal; repeat the same stroke
cycle as quickly and as efficiently as possible until he touches the
wall. There isn't alot of strategy or novel movement based on his
opponent's movements. Its simply to be the first one to finish. What
is he consciously thinking about during a race? In his post-race
interviews, he says he notices the relative positions of other
swimmers, his energy level and the overall effort required to win (and
in at least one race, the level of water in his goggles.) At his
level, the concept of automaticity (as discussed in a previous post)
has certainly been reached, where he doesn't have to consciously
"think" about the components of his stroke. In fact, research has
shown that those who do start analyzing their body movements during
competition are prone to errors as they take themselves out of their
mental flow.
Moving
up the continuum, think about gymnastics. Certainly, the skills to
perform a balance beam routine are practiced to the point of fluency,
but the skills themselves are not as strictly repetitive as swimming.
There are finer points of each movement being judged so gymnasts keep
several mental "notes" about the current performance so that they can
"remember" to keep their head up or their toes pointed or to gather
speed on the dismount. There also is an order of skills or routine
that needs to be remembered and activated.
While
swimming and gymnastics are battles against yourself and previously
rehearsed movements, sports like beach volleyball and badminton require
reactionary moves directly based on your opponents' movements. Rather
than being "locked-in" to a stroke or practised routine, athletes in
direct competition with their opponents must either anticipate or react
to be successful.
So,
what is the brain's role in learning each of these varied sets of
skills and what commands do our individual neurons control? Whether we
are doing a strictly repetitive movement like a swim stroke or a
unique, "on the fly" move like a return of a serve, what instructions are sent from our brain to our muscles? Do the neurons of the primary motor cortex (where movement is controlled in the brain) send out signals of both what to do and how to do it?
Researchers at the McGovern Institute for Brain Research at MIT
led by Robert Ajemian designed an experiment to solve this "muscles or
movement" question. They trained adult monkeys to move a video game
joystick so that a cursor on a screen would move towards a target.
While the monkeys learned the task, they measured brain activity with
functional magnetic resonance imaging (fMRI) to compare the actual
movements of the joystick with the firing patterns of neurons. The
researchers then developed a model that allowed them to test hypotheses
about the relationship between neuronal activity that they measured in
the monkey's motor cortex and the resulting actions. They concluded
that neurons do send both the specific signals to the muscles to make
the movement and a goal-oriented instruction set to monitor the success
of the movement towards the goal. Here is a video synopsis of a very similar experiment by Miguel Nicolelis, Professor of Neurobiology at Duke University:
To back this up, Andrew Schwartz, professor of neurobiology at the McGowan Institute for Regenerative Medicine
at the University of Pittsburgh School of Medicine, and his team of
researchers wanted to isolate the brain signals from the actual muscles
and see if the neuron impulses on their own could produce both intent
to move and the movement itself. They taught adult monkeys to feed
themselves using a robotic arm while the monkey's own arms were
restrained. Instead, tiny probes the width of a human hair were placed
in the monkey's motor cortex to pick up the electrical impulses created
by the monkey's neurons. These signals were then evaluated by software
controlling the robotic arm and the resulting movement instructions
were carried out. The monkeys were able to control the arm with their
"thoughts" and feed themselves food. Here's a video of this experiment in action:
"In
our research, we've demonstrated a higher level of precision, skill and
learning," explained Dr. Schwartz. "The monkey learns by first
observing the movement, which activates his brain cells as if he were
doing it. It's a lot like sports training, where trainers have athletes
first imagine that they are performing the movements they desire."
It
seems these "mental maps" of neurons in the motor cortex are the end
goal for athletes to achieve the automaticity required to either repeat
the same rehearsed motions (like Phelps and Liukin) or to react
instantly to a new situation (like May-Treanor and Dan). Luckily, we
can just practice our own automaticity of sitting on the couch and
watching in a mesemerized state.
AJEMIAN,
R., GREEN, A., BULLOCK, D., SERGIO, L., KALASKA, J., GROSSBERG, S.
(2008). Assessing the Function of Motor Cortex: Single-Neuron Models of
How Neural Response Is Modulated by Limb Biomechanics. Neuron, 58(3), 414-428. DOI: 10.1016/j.neuron.2008.02.033
Velliste,
M., Perel, S., Spalding, M.C., Whitford, A.S., Schwartz, A.B. (2008).
Cortical control of a prosthetic arm for self-feeding. Nature, 453(7198), 1098-1101. DOI: 10.1038/nature06996
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Abuse of prescription drugs, such as 
The results concluded that there was a significant improvement in
cognitive functions like attention, reaction time and mental processing
as well as physical benefits described as increased "time to
exhaustion" and decreased "perception of fatigue" in cycling and
running tests.
Which
brings us to the cover of the ball and all of the design possibilities.
Two forces affect the flight and distance of flying spheres, gravity
and aerodynamics. Eventually, gravity wins once the momentum of the
ball is slowed by the aerodynamic drag. Since all golf clubs have some
angular loft to their clubface, the struck ball will have backspin. As
explained by the Magnus Force effect, the air pressure will be lower on
the top of the ball since that side is moving slower relative to the
air around it. This creates lift as the ball will go in the direction
of the lower air pressure. Counteracting this lift is the friction or
drag the ball experiences while flying through the air.
