Jump shot definition: a shot at the basket made by a player releasing
the ball at the highest point of a leap (Collins English Dictionary, 2003).
According to Youth Basketball
Tips, (ukn year) A jump shot is
best used when you are charging down the court and cannot (or don't want to) dribble pass your opponent.
Force
Image 1, source unknown
Newtons Third Law
Newtons third law of motion is ‘for every
action, there is an equal and opposite reaction.’ (Blazevich, 2012) This law
means that if we apply a force against something that will not move, such as
the ground, then the object, the ground, will produce an equal and opposite
reaction force against the initial force. This concept is important as it
provides the knowledge that the amount of force applied to an object is equal or
opposite to the force received, and we need to understand the direction of
force applied determines the direction of the opposite force. For example, in a
running race the runners will push off a block to propel themselves forward.
Leavers
Within our body the system of muscles and
bones generate to create the movements we use within sport to manipulate
equipment. There are three classes of leavers, however we are discussing only
one through this biomedical blog. Within the body most of the leavers we use
are classified as third class leavers which is where the force or effort acts
between the load or weight (of the ball) and the fulcrum as shown in image 2.
With having majority third class leavers within the body there are some
advantages and some disadvantages. The biggest advantage of having mainly third
class leavers is it allows us to create high speeds at the end of the leavers,
such as the hands and feet. However the disadvantages are that the leavers
require the muscles systems to exert large forces, compared to the weight that
they are moving such as a ball, which can implicate injury in athletes. (Sport
New Zealand, ukn year)
Image
2, source unknown
Image
3, source unknown
The Magnus effect is the forces that work
around a sphere rotating through the air. “A rotating sphere, such as a ball,
was associated with a sideways (transverse) force,” (Blazevich, 2012) as shown
in image 3. When a ball is spinning through the air the ball grabs the air
flowing past it the friction between the ball and the air start or continues to
spin the ball. The flight of the ball can also be assisted by the knowledge
about newtons third law of opposite and equal reactions with the lift force on
the ball while spinning.
Push-Like v Throw-like movement patterns
In A throw-like movement pattern the joints
involved in the kinetic chain work sequentially which is where the Push-Like
movement pattern differs by all the joints extending in the kinetic chain
simultaneously. The push-like movement pattern is commonly used when the goal
is accuracy such as a squat whereas the throw-like movement pattern is commonly
used when speed is more importance than accuracy for example a baseball throw.
However by using two hands, such as a chest pass within netball, there should
be a high accuracy on the movement. (Blazevich, 2012)
The Answer:
The first is the preparation phase within this phase the player receives the ball and prepares to jump.
This is the
first stage of the basketball jump shot, the jump shot is work 2 points in the
game of basketball and is used when under pressure by defense and there is no
path to dribble and drive to the basket for a layup. Within this stage of the
jump shot the player receives the ball and prepares for the shot. This phase is
where the player whom is shooting the ball has their knees bent, eyes up towards the basket and having the ball in the
fingers however the player must first have both feet on the ground and have
balance to correctly execute the shot.
The main
skill cues used within this phase of the basketball jump shot are having the
players knees bent, having the player’s eyes up towards the basket and
acquiring the target. Having the knees bent is underpinned by the understanding
of force summation. As discussed earlier, by engaging the thigh muscles when
the knees are bent in preparation of the jump shot the force summation created
is larger and therefore creates a larger and greater force. This also assists
the preparation of the propulsion of the force through the legs into the torso
and through the arms upwards while releasing the ball. When the player’s eyes
are facing forward and acquiring their target the
player knows where the ball is going to go once the ball is shot. When the ball
is in the player’s fingers, the ball can pass through the air faster because
the fulcrum is between the effort or muscles and the ball.
The first phase of the basketball jump shot
is all about preparing the ball and the player for the shooting action and the
actions happen simultaneously in a linear motion. If the player has correctly
caught the ball and has their hands and legs in the correct position they are
able to complete the ‘release’ phase of the shooting action successfully, from
a bio-mechanical perspective.
The second phase is the release phase where the ball is released from the hands and ‘shot’ towards the basket.
The second phase of the basketball jump shot
is the releasing of the ball or the shooting action. Within the phase there is
3 underpinning bio-mechanics which play important parts in the release of the
ball.
The first is force, the upward force which is
created from the thighs assist the player the jump while taking the jump shot
in basketball. Without the player being able to create an upward force and
propel their body into the air vertically the jump shot would no longer have
the jump part associated to it. When the thigh muscles contract and work in
conjunction with the knees and the torso the player is able to jump into the
air and release the ball in the air.
The second is Newton’s law which is connected
to force. Newton’s thirst law of movement is about equal and opposite reactions
to force. As the player’s knees bend and the force is generated from the
thighs, the force that the body is pushing the group with is equal to the force
the group pushes back with. For example the basketball bounces on the floor but
it returns to the players hand with the same force that it was pushed downwards
towards the ground with. Also the force generated between the ball and the hand
has a equal and opposite reaction working towards the balls projection which is
why the ball should be released at the last moment after the reaction is at its
peak. As demonstrated in image 4.
Image
4, source unknown
The last underpinning bio-mechanics within the
release phase of the basketball jump shot as discussed within this blog is the Push-Like
and throw-like movement patterns. Within the basketball jump shot the aim of
the shot is to throw the ball with speed through the air and into the basket to
score 2 points. With the use of the extended joints in the kinetic chain
working sequentially together to shoot the ball, the throw-like movement patter
is better to use due to the joints working one at a time to create the force
and the speed to throw the ball through the basket. There is also the
consideration that the push-like movement pattern would be better used because
of the outcome of accuracy over speed however because an accurate shooting
action uses both hands to compete the shot, one for guidance and one for
shooting, the accuracy of the shot is increased by the use of both hands over
one.
The third phase is the follow through phase where the ‘shot’ is completed.
The final stage of the basketball jump shot
is the follow through phase where the ball had been shot. This phase of the
shot is dependent to all the variables within the last two phases such as
height of the player, the release of the ball, the back spin on the ball, the
projective of the ball and the way the body returns back to the ground. The
biggest skill cue within this phase is the effectiveness of the swan hand after
the shot. The swan hand demonstrates that the ball has left the hand from the
shot with backspin, as shown in image 5. This is important as we have discussed
earlier the Magnus effect of sphere shapes. The ball is spun it grabs the air
around it and uses the friction between itself and the air to continue spinning
through the air. This is important as within basketball there is a backboard
and it has been apparent that is a ball traveling towards the basket has back
spin there is more chance the ball will use the evidence of newtons third law
and bounce off the basket with equal and opposite force and spin into the
basketball.
This phase is about finishing the shot and
then moving the body to be ready to move into the next action.
Image
5, source unknown
How else we can use this information
The information provided within this blog
would be relevant to use when playing a sport which involves scoring baskets
through a shooting action. As discusses the bio-mechanics underpinning the
basketball can be useful for different sports and aspects of sports.
Force can be used in relation to a rebounding
of the ball situation in basketball, netball or Korfball. As an example the
force which is generated within the thighs and used to propel the player
upwards would assist a player to collect a rebound over another player, if
enough force is generated. It would also be effective to use the provided
information to understand the jumping of the ruck-men in the Australian Rules
Football League, the players have to propel themselves off the ground as high vertically
as they can to tap the ball to their team mates. Force also is relate able to
Newtons third law of motion, for an example, the force of the kick on a soccer
player will give an equal and opposite reaction to the ball and propel the ball
forwards or backward depending where the force is intended.
Push-Like and throw-Like movement pattern
occur in every movement we do for example, when doing sit ups in the gym or
push ups the movement pattern used is push-like and when a ball is thrown from
one player to another or kicking a ball. The different between to two is
throw-like movement pattern has an emphasis on speed of the object, like a fast
chest pass in netball, and the push-like movement pattern is for such
activities that require accuracy in the movement and speed is not an outcome
such as a rugby scrum, where the aim is to accuracy move the other players away
from the ball.
The Magnus effect can have implications
within the game of goal by creating movement of the ball from a straight
direction to a curved direction when a long shot is played. Because the ball
has a smaller mass the friction created between the air and the ball is smaller
than the example with the basketball and the ball grabs the air differently. Due
to the ball grabbing the air differently the air rotates and ball is a
transverse direction which changed the direction from a straight trajectory to
a curved trajectory.
Lastly having an understanding of leavers is
fundamental to most sports as they involve the movement of limbs in relation to
your torso. There are other classifications of leavers however these are not
described within this blog due to them not being relevant to the basketball
jump shot directly.
When considering a bio-mechanics aspect of the
basketball jump shot there requires some planning and understanding of the terms
and what they mean in relation to the jump shot. According to Blazevich (2012, p. 210) “A
detailed plan is very important in order that the most influential bio-mechanical flaws are noticed and corrected.” Through
coaching and better understanding of the bio-mechanics which underpin the
basketball jump shot players should be able improve an aspect of their shot
once the understanding can be related back into a game situation.
References
Blazevich, A., J. (2012). Sports Biomechanics the Basics: Optimising Human Performance. Bedford Square, London:
A&C Black Publishers Ltd
Collins English Dictionary.
(2003). The Free Dictionary: jump shot. Retrieved
from http://www.thefreedictionary.com/jump+shot
Sport New Zealand. (Ukn. year). Module Five: Introduction to Biomechanics.
Retrieved from; http://www.sportnz.org.nz/Documents/Communities%20and%20Clubs/Coaching/l2-module5-a.pdf
Wuest, D., Fisette, J., (2012)
Foundations of Physical Education, Exercise Science, and Sport, (7th Edition)
New York.
Youth Basketball Tips, http://www.youth-basketball-tips.com/jump-shot.html
