Introduction
The free throw, in particular, is especially important because it
provides an opportunity for a team to score free uncontested points (Malone,
Gervais, Steadward, 2002). One point can
make all the difference between victory and defeat. The foul shot line is 15
feet from the rim and you have 10 seconds to shoot, hence, the free throw
should be one of the easiest shots in basketball. The highest free throw
percentage during the 2003-2004 NBA regular season was 92.7%. On the other
hand, some players made less than 50%. The lower percentage shooters often
shoot with little backspin, which hits the rim, backboard, or the bridge
between the rim and board and leave the sagittal plane (Okubo & Hubbard,
2006).
There are two successful
techniques used to shoot a foul shot in basketball, the underhand loop shot and
the over hand hook shot. Underhand loop shot has a stepper angle of entry and
smaller drift of the ball from better stability provided by holding the ball
with both hands and applying greater spin. Rick Barry, former NBA All-Star forward is the
second-best free throw shooter of all time at 90.0% used the underhanded shot (Reilly
2006). Although in the current game the underhand loop shot is rarely used as
it doesn’t transfer to the shooting technique required in a game situation as
well as players being concerned with the image of the shot, as they say it’s
ugly and players are too concerned about what they look like (Reilly 2006). Therefore
the over hand hook shot is the most common technique used in today’s game. Using
the over hand hook shot technique we are going to analyse how to optimise the
art of a foul shot.
The Phases
The saying ‘practice makes perfect’ is somewhat
correct when it comes to foul shooting, although it is essential for a
successful foul shooter to have the mentality ‘proper practice makes perfect’. A foul shot should reoccur the same
mechanics in every attempt. The phases are a basic base on what a shooter
should perform over six stages.
Phase one: Preparation.
Begin with a wide base
of support to ensure stability feet shoulder width apart and position the
shooting arm at approximately a 90 degree angle at the elbow. The shooting hand
behind the ball supporting hand beside the ball for stability ball around eye
level and have a focus point.
Phase two: Force
Production.
Flexion at the knee and
the hip and dorsiflexion at the ankle.
Phase three: Upward
Acceleration.
Extension should occur
at the knees and hip and plantar flexion at the ankle. The weight distribution
should be moving towards the heels.
Phase four: Transfer of
Power.
A transfer of power will
follow from the lower limbs via kinetic linking. The shooting elbow almost at
full flexion, while the other hand, also known as the guide hand is resting
gently on the side of the ball. An increase of hip extension as the shooter is
moving into upright position.
Phase five: Shot
initiation and Action.
The elbows will almost
be in full extension and flexion should occur at the shoulders and wrist. The
ball is brought up above eye level and released.
Phase six: Shot Follow
Through.
Wrist is in full flexion
with a very important 'wrist flick' both elbows in complete extension with full
upward extension of the body on the toes.
The Mechanics
Within the phases, there
are four major principles that effect the shot. The principles include, force,
impulse, angular position and torque. Below will summarise how these principles
work.
Force is used in
reference to Newton’s 3rd law of motion: for every action there is
an equal and opposite reaction. Therefore, if the force is sufficiently large
and force is directed appropriately, there will be acceleration in the desired
direction (Blazevich, 2010).
Impulse is best
described as the product of force and time. Essentially the greater the
impulse, the greater the change in momentum, this is the impulse-momentum
relationship which gives hints how best to accelerate our body (Blazevich,
2010).
There are two focus
points for angular position, angular displacement and angular velocity. Angular
velocity is the rate of change in the angle of performer. Angular displacement
is the angle that a rotating body goes through. In this instance the path travelled is directly proportional to the
angular displacement of the hand at the wrist
Torque is a measure of how much force is acting on an
object that causes the object to rotate.
THE ANSWER
To answer the question,
using the phases from above and breaking them into three basic phases, we will
analyse the impact four major biomechanical factors, which have a significant
impact on the art of a foul shot. These include force, impulse, angular
displacement, angular velocity and torque. Lets analyse how to optimise the art
of a foul shot..
Firstly, the Preparatory
Phase/ Wind Up Phase. To begin it is important to be relaxed and block
out irrelevant cues; try to practice having the mindset as though you’re in a
game, it makes the skill of relaxing easier and think about the mechanics of
the shot you have practiced away from a game situation. The mechanics and
phases of the shot you should recite are as follows.
Position the legs
shoulder width a part. A right-handed shooter should place right foot slightly
further forward than their left, approximately making a 30-degree angle, as in
Figure 1 and the opposite for a left
hand shooter. The shoulder width stance creates a better balance and stable
base. Once in stance, bend the knees, lowering the centre of gravity. The
higher the centre of gravity above the base of support, the less stable the object
is. Athletes often lower their centre of gravity by bending the knees in order
to increase stability (Smyth, Brown,
Pritchard, Gervasoni, Wright, 2009).
FIGURE 1.
It is important to have
a routine, whether it is spinning the ball to yourself and/or taking a dribble
or two before the shot, as seen in Figure 1.1. Try and do this every time, becoming a rhythmic
sequence. Focus on the target; generally people try teaching someone to focus
one of 1 of 3 points in the follow through on their shot: 1.Behind the ring, 2.Inside
the ring, 3.For the rim Figure 1.2. Get
the ball on your fingertips, meaning leave a space between the ball and palm of
your hand. Having the ball in the palm of your hand gives you a lot less
control of the ball compared to having the ball in your fingertips. Bend the
elbow at a 90-degree angle (L-shaped) at the ring. Bend knees further, the legs
are to produce the force for the basketball to reach the basket. Lift the ball,
keeping the elbow in close to the body and not allowing it to flare out. The
relative height at take-off affects the angle of approach. The height of the
shot will be more successful if the shot starts at eye level as opposed to
lower near chest or stomach. As in Figure 1.3,
FIGURE 1.2 The arrow point to the areas of focus.
FIGURE 1.3. Performer has ball in your fingertips, bent the elbow at a 90-degree angle (L-shaped) at the ring, knees bent. Ball is lifted to eye level as opposed to lower near chest or stomach and positioned the ball slightly to the right.
We now follow onto the Force
Producing Phase. To produce force we need to refer to Newton’s 3rd
law of motion; for every action there is an equal and opposite reaction. This
law means that if we apply a force against something that doesn’t move the
object will exert an equal and opposite reaction force against us. This
reaction force is important for two reasons. First, to have the greatest force
applied to us, we need to apply the greatest possible force against that
object. Second, if we need the force to accelerate us to a specific direction,
we need to produce it in a very specific, and opposite, direction (Blazevich,
2010). Flexion at the knee and the hip and dorsiflexion at the ankle facilitate
downward acceleration. Forces are being built up the legs by the shooter
flexing at the knees, as in Figure 1.3.
The impulse is dependent on the magnitude of the forces exerted and the time
that the forces act. The kinetic linking occurs to transfer the force generated
in the legs up the arms to the wrist. As extension occurs at the knee the force
begins to transfer through the legs and up through the arms to the wrist
through kinetic linking to increase acceleration (Brimmell, 2012). The Impulse can be modified to
improve performance by optimizing the magnitude of the forces acting on the
ball; the ultimate situation consists of the performer producing the most force
over a relatively short period of time. Therefore you want one slick and quick
movement, with your eye on your target we now get carried onto the follow
through phase...
FIGURE 1.4. Follow through phase in finalisation, from front.
FIGURE 1.5. Follow through phase in finalisation, from back.
The follow through phase
is the execution of the shot. The guide hand goes in straight line up with the
shot helping to guide and shooting hand should be flicked down at the target
and the body should be upright, on toes as shown in Figure 1.4 and Figure 1.5 It is very
important during shot initiation that the wrist starts in full extension and at
the end of the follow-through phase the wrist should be in full flexion. The
path travelled is directly proportional to the angular displacement of the hand
at the wrist. Angular velocity is another factor and can be modified by
decreasing the amount of time taken to produce full flexion of the hand at the
wrist. A fast ‘flick’ of the wrist will produce a faster angular velocity. The
angular velocity with which the ball leaves the hand determines the arc height
and distance and thus determines if the ball will make it to the hoop. Most of
the time you will shot with the 3 fingers, as show in Figure 1.6. If the other two fingers come into play the ball will
begin to shoot with different rotation, rather than backspin. The spin of the
ball, like every shot, should be spun backwards. Torque enables the shooter to
provide backspin on the ball. When extending the arm and snapping the wrist
downwards your fingers will push the ball out of your hands and pull the seams
downward creating the backspin on the ball (Brimmell, 2012). To improve torque
and maximize backspin the shooter could change the amount of force applied at
the wrist o the perpendicular distance of the ball to the wrist, relating to
where the ball is sitting on your hand. To optimize torque the performer should
make sure the ball rollers of the fingers tips during shot, the middle finger
should be the last finger on the ball, hence it has the most impact on the
backspin and direction of release. If you shoot without backspin then you are likely to
have the ball bounce violently back to you, whereas, the backspin helps
increase the chance of the basketball bouncing into the rim, a term known as
the ‘lucky bounce’.
Video 1 demonstrates a routine performed by a player which puts all the
above phases together.
VIDEO 1. Sequence of foul shot.
HOW ELSE CAN WE USE THIS INFORMATION?
Such analyses can
be used by biomechanists to better understand the factors influencing
performance in many sports. Understanding position velocity and acceleration
also can help us work out tactics for many individual and sports teams
(Blazevich, 2010). Therefore, not only is it useful in a particular technique
but also in a team situation to understand which athlete can be most successful
in certain areas for team tactics, such as who can jump the highest of and/or who
has the fastest acceleration. Although it is
not just the performers but also the coaches and teachers who can use the
knowledge gained for reasons such as, understanding the principles of sports to
discovering new and more effective techniques for skills to aiding injury
prevention and rehabilitation.
When it comes to
forces; while it might seem a simple concept that producing forces in a
specific direction is important for sporting success, too few athletes and
coaches consider how to optimise force production (Blazevich, 2010). Force
production is a major factor of the foul shot, the shooter has to produce enough
force for the ball to make it to the ring, but not too much so we over shoot. To
have the optimum level of force production is similar in many sports, for
example, when bowling a cricket ball, if you bowl too hard the ball is more
likely to be inaccurate and when not producing enough force the batsman has an
increased chance of hitting the ball and hitting the ball further. It is important to understand the
successful amount of force to produce within the desired skill for optimum
achievement.
Finally, all the
information stated throughout can also be transferred into other sports and
skills. Whether it’s within the game of basketball, where converting similar
techniques into a jump shot or whether its netball and the understanding of
balance stability or optimum angle of approach. Further biomechanical detail
can be explored to work out the optimum angle of release. Which would lead to
further discussion in areas such as, does a player’s height influence the
mechanics of the shot?
References:
Blazevich, A. (2010). Sports biomechanics, the basics: Optimising
human performance. A&C
Black.
Brimmell, M. (2012). Qualitative
Anatomical Analysis of a Basketball Free Throw Shot. Prezi Presentation, 24 November 2012
<http://prezi.com/suy5xhslnvxs/basketball-free-throw>
Malone, L., Gervasis, P, Steadward, R.
2002. Shooting mechanics related to player classification and free throw
success in wheelchair basketball. Journal
of Rehabilitation Research and Development 39.6 (Nov/Dec 2002): 701-9.
Okubo, h., Hubbard, M. (2006) Dynamics of the basketball
shot with application to the free throw. Journal
of Sport Sciences. Volume 24, Issue 12
Reilly, R. (2006).
Paging Dr. Barry. Sports Illustrated,
105, 124.
Smyth, D., Brown, H., Pritchard, R.,
Gervasoni., Wright P. 2009. Live It Up 1 VCE Physical Education Units 1&2. Volume 4 of Live It up Series. Australia. John Wiley &
Sons
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