What Biomechanical knowledge is required to enhance/improve basketball
players lay ups?
The basketball layup shot for goal is most commonly used if a
player is dribbling towards the basket and doesn’t want to pass the ball and
can get around the defenders. Its accuracy is also a cause for why it is so
popular. For a player to improve their layup, improve accuracy, make the shot
more efficient and speed up the run into the shot it is important to look at a
few biomechanical principals. These principals tell us how to move our body
efficiently and improve our skills.
Biomechanics is concerned with two areas of study. The biological
area; the biological aspects for movement and motion in the human body; and the
mechanics; this utilizes Newtons laws and principals and applies them to human
movement and motion (Wuest & Fisette, 2012). Biomechanists study how
various forces affect human motion and how movements can be improved in terms
of efficiency and effectiveness (Wuest & Fisette, 2012).
In the layup shot the player runs towards the basket while
dribbling the ball in their right hand, they then place their right foot
followed by their left and take off, releasing the ball towards the basket by
completely extending their shooting arm (Sandeep & Bhardwaj, 2011). The layup
is considered one of the more basic shots in basketball. The main obstacle when
performing a layup is getting near the baskets rim and avoiding the taller
defenders blocks (Sandeep & Bhardwaj, 2011). The layup is made with one
hand and from a position under or beside the basket (Sandeep & Bhardwaj, 2011).
Biomechanics relating to the
preparation phase of the layup (the run up).
Momentum
To change an objects momentum we have
to apply a force, the larger the force, the greater the change in momentum. When
a player hits the ground with their feet, they need to apply the largest force
possible for the longest time possible. The greater the impulse, the greater
the change in momentum; since our mass will change, our velocity should (Blazevich,
2010).
When a player’s foot lands at a greater angle in front of the
body the braking impulse is large. The total positive impulse is therefore
smaller so acceleration is smaller. When a players foot lands at a smaller
angle and further under the body, the braking impulse is smaller (Blazevich, 2010).
The total positive impulse, however, is likely to be larger. So while players
want to minimise the braking force, a small force plays a large role in the
ability to run at high speeds (Blazevich, 2010). In sprinting, the braking
impulse is usually greater when the foot lands further in front of the body;
there is a trade-off where a small braking force is useful but a large force,
generated when the foot lands well in front of the body’s centre of mass, is
detrimental (Blazevich, 2010). However, in basketball braking and sideways impulses
are important for the players who need to slow down and change direction
quickly. In the layup the dribble towards the basket needs to have some speed
however, the two steps before the jump should be controlled and slower. From
this information we can also say that when running and dribbling player’s feet
should not land on their heels, more like the middle.
Newtons First Law
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
(inertia) (Blazevich, 2010). All objects that have a mass have inertia, the
larger the mass of an object the more difficult it is to change the objects
state of motion (Blazevich, 2010). So if players want to jump higher, they need
to work out how to change their state from rest or from a constant horizontal
running velocity to vertical motion. In basketballs case this is when the
player takes those two steps and uses their legs to throw their bodies into the
air to reach the basket.
Newton’s second law
Newton’s second law states that the acceleration of an object
is proportional to the net force acting on it and inversely proportional to the
mass of the object (Blazevich, 2010). To
change the state of motion of an object, we need to apply a force. The formula
f=ma informs us that the lighter the object, the faster it will accelerate, or
that less force will be needed to cause a given acceleration (Blazevich, 2010).
The lighter a person is, the more they can accelerate their body under a given
force.
This also applies when players are moving the ball up into
the basket. They need to understand how much force to place on the ball to get
it up and through the hoop. Players need to understand the balance between too
much force (causing the ball to go out of control) and too little force (the
ball doesn’t get enough height). This knowledge of how much force to apply to
the ball comes with practice.
What biomechanical aspects
relate to the power production phase of the layup (the jump)?
Centre of Mass
In evasive sports such as basketball, players try to move
their centre of mass around an opponent, but to evade them they only need part
of their body to be out of reach at any one point (Blazevich, 2010). In basketball,
players might try to ‘hang’ in the air to block a shot or provide upper body
stability to make a shot of their own. Players do this by bringing their legs
up and under their body after they leave the ground during a jump (Blazevich, 2010).
When someone would normally be about to fall back down towards the ground under
the influence of gravity, players rapidly extend their legs downwards, to
conserve momentum, their upper body moves upwards (Blazevich, 2010). In effect,
since their body’s centre of mass is moving downwards but, relative to it, their
upper body is moving upwards, their upper body momentarily remains stationary
or ‘hangs’. Another important use of this centre of mass information is in
helping players obtain balance during complex skills (Blazevich, 2010). This
technique is useful when performing the jump in the layup; players want to have
as much air time as possible.
When accelerating during running it is helpful for players to
allow their centre of mass to move forward of their base support, this will
cause a forward rotation of their body. This rotation, which is caused by the
force of gravity, provides a forward acceleration that helps us move. By
players implementing this rotation it helps with their movement efficiency.
Magnus Effect The most common explanation of the Magnus’s effect is that the spinning ball ‘grabs’ the air that flows past it because of the friction between the air and the ball, so these air particles start to spin with the ball (Blazevich, 2010). According to the Magnus effect, if a player puts spin on the ball, where the top of the ball spins over the bottom of the ball (i.e. top spin), the air on top will slow down and the air underneath will move relatively quicker (Blazevich, 2010). Therefore, the pressure on top of the ball would be higher, a Magnus force would be directed down towards the ground and the ball would dip. This can help shooters to get the basketball to hit the back board and fall into the hoop.
Newtons
Third Law
Newton’s third law states that for every action, there is an equal
and opposite reaction (Blazevich, 2010). When a player steps onto the ground a
vertical downward forced is applied. The ground exerts an equal and opposite
reaction force, this is called the ground reaction force (GRF), which stops player’s
feet from sinking into the earth. During running and jumping, players apply a
force with both vertical and horizontal components (Blazevich, 2010). The ground
exerts equal and opposite GRF, which can accelerate us forwards if the force is
large enough to overcome our inertia (Blazevich, 2010). It is very important to
produce large vertical forces, or have a lower body mass, to jump very high. For
the layup this means players must use the power in their legs to propel them
into the air, towards the hoop.
Jump– work,
power, energy, and efficiency:
The amount of work when someone jumps is equal to the average
force that is applied multiplied by the distance over which it is applied. Several
forces might act at any one time (Blazevich, 2010). The concept of work is
important in sport in general, because we often need to manipulate it. The
greater the total work done the better the performance will be (Blazevich, 2010).
At any time, the greater the force, or the faster the velocity,
the power is greater. Power is increased when players do a given amount of work
in less time or do more work in a given time (Blazevich, 2010). Increasing power
results in an increase in the velocity of an object, as long as its mass
remains constant. This principal also applies to people (Blazevich, 2010).
To jump up high, a basketballer has to perform a greater
amount of work, or attain higher power but they also need to repeat such jumps
numerous times in a game (Blazevich, 2010). If players jump in the air they
increase their potential energy. This also means that players need to have a lot
of energy to repeatedly perform jumps and movements throughout the game.
Efficiency is the ratio of energy output to input (Blazevich,
2010). To improve a players jumping efficiency, not just their jump height,
they need to increase the output (kinetic energy, resulting in greater jump
height) while decreasing the input (the energy required to jump) (Blazevich, 2010).
The power that players use to jump comes from muscle contraction.
Follow through and recovery
phase aspects
The kinetic chain
One of the kinetic chain pattern categories is the push-like
movement pattern. A push-like movement pattern is when a person moves as if
they are pushing something. Players tend to extend all the joints in their
kinetic chain simultaneously in one single movement (Blazevich, 2010). The benefits
of using a push-like movement pattern are that the joins are acting simultaneously
the cumulative forces (torques) generated about each joint result in a high overall
force, it is efficient, highly accurate, and results in a straight-line
movement at the end point of the chain (Blazevich, 2010). However, a drawback
of the push-like movement is slow movement speed (Blazevich, 2010). However, in
the layup this slow movement speed can be helpful to players; it allows them
more control over the ball. The throw-like movement pattern produces higher
speeds but this isn’t an attribute required for the layup, the ball does not
have to travel at high speeds when performing the shot.
A flick of the wrist directs the ball into hoop. Once the
ball is released from the players hand the fingers must follow in a flick like
motion with the wrist. This helps direct the ball into the hoop and ends the
kinetic chain completely.
Landing – landing with soft knees. As with
any landing it is important for players to land with soft knees
Layup sequence and relevant
skill cues according to phase
Preparation
Phase (Thurston,
2011):
Players dribble towards the basket
Players take two steps
Player’s eyes should be focused on
the top right square of the backboard
Players should dribble with the
outside hand
Power
Production Phase (Thurston,
2011):
Players then jump up – step right
and jump off their left foot
Player’s right knee bends up
Players then extend their arm and
release the ball at the peak of reach
Follow
Through Phase:
Players then flick their wrist
downwards
Players then land with soft knees
How else can we use this
information?
This blog demonstrates the many
different biomechanical aspects related to the basketball layup, these aspects
also transfer into other skills in basketball as well as many other sports.
Other basketball shots have the same biomechanical aspects involved in them. Some
of the biomechanical aspects covered also apply to a person’s general running
technique. Many aspects cross over into other sports, but the most closely
linked sport would be netball.
If players take into consideration
the biomechanics of the shot they can improve not only their technique and accuracy
but also protects the longevity of their bodies. With the biomechanical aspects
in mind players and coaches can work together to learn and practice the shot to
the best of their ability.
Through biomechanical analysis of any
skill from any sport the aspects can be interpreted to achieve the best outcome
and movement pattern relating to the skill. For teachers, players and coaches
the information gained from biomechanics can give them the background information
needed to teach the basic skill and then later refine and advance that skill.
Biomechanics is not just necessary for the older more experienced players. In
some cases it is more important to inform younger players the reasons why we
run a particular way. It is better for them to form good habits younger as it
is harder to change habits as players get older. Although some skill techniques
can differ due to individual preference, more players can find more success and
accuracy when applying the correct biomechanical principals.
References:
Blazevich, A.J. (2010). Sports Biomechanics: The basics optimising
human performance. (2nd ed.). London A&C Black.
Sandeep, K., Bhardwaj, B.
(2011). Relationship among Selected Biomechanical Variables with Lay Up Shot
Performance of Basketball Players. VSRD
Technical and Non-Technical Journal, 2(5): 229-233.
Thurston, T. (2011). Basketball
Skills. Shooting. Viewed on 15 June 2014. Available at http://edtech2.boisestate.edu/travisthurston/502/basketball/shoot.html
Wuest, D., Fisette, J. (2012).
Foundations of Physical Education, Exercise Science, and Sport (17th
ed). McGraw-Hill New York.
Images:
Progression
shot = https://guywithglasses.com/portfolio/illustration/basketball-sequence-illustration-springfield-college
Jump shot = http://www.knoxnews.com/photos/galleries/2012/nov/09/tennessee-76-kennesaw-state-67-mens-basketball/56008/
