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| Ray Allen is one of the best foul shooters with a career average of 89.39% |
Introduction
The foul shot is one of the most important
shots to make in basketball. All basketball players must be efficient from the
foul line because it can be a determining factor in the result of the game.
Repetition of practicing foul shots, a set routine at the foul line and sound
technique help in a high success rate of foul shot makes. The basic technique
for a foul shot is as follows:
·
Have the same foot as your shooting hand
slightly forward of the other foot.
·
Bend at the knees and as the ball is almost
released, rock upwards onto the toes.
·
Support ball with the hand of your non-shooting
arm.
·
Keep forearm vertical before shooting.
·
Shoulder, elbow, and wrist should be in line
with the rim before shooting.
·
During shooting, ball should move from below
the chin towards an upward and forward direction.
·
Extend elbow fully at the ball release.
·
Follow-through by snapping wrist forward, so
that the shooting hand is facing downward.
·
Release ball with your fingertips.
·
Hold follow-through (keep wrist firm) until
the ball reaches the rim (Lam, Maxwell & Masters, 2009).
How to create power in a foul shot?
Newton’s laws of motion explains force
production in a variety of sporting movements, including the basketball foul
shot. Newton’s first law states that “An
object will remain at rest or continue to move with constant velocity as long
as the net force equals zero” (Blazevich, 2010, p.44). An object that stays in
its present state is called inertia and all objects that have a mass have
inertia including a basketball (Blazevich, 2010). The larger the mass, the more
inertia there is. Having a higher amount of inertia makes it difficult to
create velocity of an object, stop an object and for the object to change
direction (Blazevich, 2010). The foul shooter needs to create force, and can do
so by using Newton’s third law, ground reaction force. “For every action, there
is an equal and opposite reaction (Blazevich, 2010, p 45). Ground reaction
force is present during the foul shot. When the foul shooter foot contacts the
ground, the ground uses an equal and opposite reaction force (Blazevich, 2010).
This allows the shooter to create enough force to overcome the inertia and
propel the ball towards the ring. Newton’s second law allows the shooter to get
power in the shot. “The acceleration of an object is proportional to the net
force acting on it and inversely proportional to the mass of the object (F = M
x A)” (Blazevich, 2010, p 45). A foul shooter must apply force to create motion
of the ball.
Notice how Steve Nash gets a lot of power from his knees and extends upwards vertically. Steve Nash is the most successful foul shooter in NBA history making 90.43% of his total foul shots.
The sum of forces is the momentum given to the
object by each body part and occurs sequentially. To generate maximum momentum
using each segment of the body from the large muscles in the legs into the
small muscles last to generate force. Correct timing, through to the
great range of motion will gain maximum momentum (Brancazio, 1981). To attain
power and efficiency in the foul shot the whole body is used. The shot begins
with the movement of the legs, pushing into the ground. The force then travels
from the legs into the shoulders, into the forearms and into the tips of the fingers
when the ball is released (Brancazio, 1981).
Momentum
is needed to exert the force needed to get the object moving to overcome
inertia. In order to change an objects momentum we
need to apply force. To accelerate vertically we need larger vertical impulses,
this will propel us into the air. Impulse is a production of force and time
therefore the greater the impulse the greater the change in momentum
(Blazevich, 2010). This principle is more prevalent in the basketball jump shot,
however it is still required in the foul shot because momentum is needed to
overcome inertia.
What is the ideal projection for a foul shot?
The angle of the foul shot is determined by the height of the player. Research
by Gablonsky and Lang (2005) found that the taller the person, the better the
free throw shooter should be. Their height allows them a larger margin of error
for the angle of the shot. If a tall player is having issues with foul
shooting, it is caused by the player shooting at a wrong angle or inconsistencies
in their release angle and release velocity (Gablonsky & Lang, 2005).
Shorter basketball players need a larger release angle and this is due to
shorter people having to cover more distance vertically (Gablonsky & Lang, 2005).
The
trajectories that allow the biggest margin of error go through the basket
between the center and the back of the rim (Gablonsky & Lang, 2005). The
shorter the player, the closer to the back of the rim they should aim (Gablonsky
& Lang, 2005). Tran and Silverberg (2008) suggest that the best release for
a foul shot is between 52 and 53 degrees and the top of ball’s trajectory is just 4cm
below the top of the backboard. The player should aim at the back of the rim so that the gap between the ball and
the back of the ring as the ball passes through the ring is about 5 cm (Tran
& Silverberg, 2008). The player should release the ball as high above the
ground as possible, as long as this does not adversely affect his launch consistency
and the player should release the ball so it follows the line joining the
player and the basket (Tran & Silverberg, 2008). The player should launch
the ball with a smooth body motion to obtain a consistent release (Tran &
Silverberg, 2008).
The best release angle is between 53-53 degrees
Table 1. Optimum Trajectories for People of
Various Heights
Height
|
Height (m)
|
Release Angle (°)
|
5’
|
1.52
|
56.64
|
5’1”
|
1.55
|
56.47
|
5’2”
|
1.57
|
56.31
|
5’3”
|
1.60
|
56.14
|
5’4”
|
1.63
|
55.97
|
5’5”
|
1.65
|
55.80
|
5’6”
|
1.68
|
55.63
|
5’7”
|
1.70
|
55.45
|
5’8”
|
1.73
|
55.28
|
5’9”
|
1.75
|
55.11
|
5’10”
|
1.78
|
54.94
|
5’11”
|
1.80
|
54.77
|
6’
|
1.83
|
54.60
|
6’1”
|
1.85
|
54.43
|
6’2”
|
1.88
|
54.25
|
6’3”
|
1.91
|
54.08
|
6’4”
|
1.93
|
53.91
|
6’5”
|
1.96
|
53.74
|
6’6”
|
1.98
|
53.57
|
6’7”
|
2.01
|
53.40
|
6’8”
|
2.03
|
53.22
|
6’9”
|
2.06
|
53.05
|
6’10”
|
2.08
|
52.88
|
6’11”
|
2.11
|
52.71
|
7’
|
2.13
|
52.54
|
7’1”
|
2.16
|
52.37
|
Source: Gablonsky &
Lang, 2005.
Magnus effect is the changing of trajectory of an object towards the
direction of spin which is the result from the Magnus Force (Blazevich, 2010). Magnus
force is the lift force acting on a spinning object (Blazevich, 2010). As
backspin on a basketball increases, the capture area becomes larger (Hubbard
& Okubo. 2006). Brancazio explains that back spinning balls experience a
greater decrease in translational and total energy than a forward spinning ball
when it makes contact with the ring. Putting back spin on a free throw (or any
basketball shot) is very important. If back spin is applied on a foul shot,
there is more chance of the ball bouncing up and going through the ring, even
if the shot is too long or short (Hubbard & Okubo, 2006). A player should
release their shot with approximately 3 Hz of back spin (Tran & Silverberg,
2008). 3 Hz translates to the ball rotating backwards approximately three times
before reaching the hoop (Tran & Silverberg, 2008). It is actually
difficult for a shooter to put more than 3 Hz of back spin on a ball without
having a negative effect on the consistency of the shot release (Tran &
Silverberg, 2008).
The biggest impact on missing foul shots is the velocity of the ball
when released. It is more important for the player to use the right velocity as
compared to the correct angle of release (Tran & Silverberg, 2008). A study
conducted by Mullineaux and Uhl (2010) on college players in America found that
slower ball release was found to distinguish misses from swishes in a foul shot.
The study found that the change in release speed is caused by the player perceiving
the technique to be inappropriate and trying to correct the shot (Mullineaux
& Uhl, 2010). By having a release velocity close to the perfect velocity,
the foul shooter is able to have a bigger margin of error in terms of release
angle. As can be seen in table 2 below, most shooters have an error range of
2-2.5 degrees in their release angle if the velocity of their release is
correct.
Table 2. Optimum Release Velocity and Max Error in Angle Release
Height
|
Height (m)
|
Release Velocity (m/s)
|
Max Error (°)
|
5’
|
1.52
|
7.34
|
2.08
|
5’1”
|
1.55
|
7.32
|
2.09
|
5’2”
|
1.57
|
7.29
|
2.11
|
5’3”
|
1.60
|
7.26
|
2.13
|
5’4”
|
1.63
|
7.24
|
2.15
|
5’5”
|
1.65
|
7.21
|
2.17
|
5’6”
|
1.68
|
7.18
|
2.18
|
5’7”
|
1.70
|
7.16
|
2.20
|
5’8”
|
1.73
|
7.13
|
2.22
|
5’9”
|
1.75
|
7.10
|
2.24
|
5’10”
|
1.78
|
7.08
|
2.26
|
5’11”
|
1.80
|
7.05
|
2.27
|
6’
|
1.83
|
7.02
|
2.29
|
6’1”
|
1.85
|
7.00
|
2.31
|
6’2”
|
1.88
|
6.97
|
2.33
|
6’3”
|
1.91
|
6.95
|
2.35
|
6’4”
|
1.93
|
6.92
|
2.36
|
6’5”
|
1.96
|
6.89
|
2.38
|
6’6”
|
1.98
|
6.87
|
2.40
|
6’7”
|
2.01
|
6.84
|
2.42
|
6’8”
|
2.03
|
6.82
|
2.43
|
6’9”
|
2.06
|
6.79
|
2.45
|
6’10”
|
2.08
|
6.76
|
2.47
|
6’11”
|
2.11
|
6.74
|
2.49
|
7’
|
2.13
|
6.71
|
2.50
|
7’1”
|
2.16
|
6.69
|
2.52
|
7’2”
|
2.18
|
6.66
|
2.54
|
7’3”
|
2.21
|
6.64
|
2.55
|
Source: Gablonsky & Lang, 2005.
How does this translate into a good
foul shot?
Taking a foul shot is a whole body technique but most people do not realise this. As the power needed to make the shot comes from the summation of forces, the initial power is created from the legs and sequentially works its way up through the body into the arms. The basketball shot is a push-like motion which helps create force because all joints act together creating a high overall force (Blazevich, 2010). The angle of release is important in a foul shot, but having a sound velocity at the release is more important because it allows for the shooter to have a higher margin of error for the angle of release. Putting back spin on the ball allows for the shot to be either too short or long and still have the possibility to bounce of the ring or backboard and still go through the hoop.
Ben Wallace is the worst foul shooter in NBA history. Has made only
41.80% of total foul shots attempted.
References:
Blazevich,
A. (2010). Sports Biomechanics, the
Basics: Optimising Human Performance. A&C Black.
Brancazio, P. J. (1981). Physics of Basketball.
American Journal of Physics, 49(4), 356-365.
Gablonsky, J. M., & Lang, A. S. (2005).
Modelling Basketball Free Throws. Siam Review, 47(4), 775-798.
Hubbard, H & Okubo, M. (2006). Dynamics of the
Basketball Shot with Application to the Free Throw. Journal of Sports Science,
24(12), 1303-1314.
Lam, W. K., Maxwell, J. P., & Masters, R.
S. W. (2009). Analogy Versus Explicit Learning of a Modified Basketball
Shooting Task: Performance and Kinematic Outcomes. Journal of Sports Sciences,
27(2), 179-191.
Mullineaux, D. R., & Uhl, T. L. (2010).
Coordination-variability and kinematics of misses versus swishes of basketball
free throws. Journal of sports sciences, 28(9), 1017-1024.
Tran, C. M., & Silverberg, L. M. (2008).
Optimal Release Conditions for the Free Throw in Men's Basketball. Journal
of Sports Sciences, 26(11), 1147-1155.
