Monday, April 22, 2013

What are the biomechanics principles of a basketball lay-up?

The Question:

What are the biomechanics principles of a basketball lay-up?

Introduction

A lay-up is one of the most fundamental actions in the game of basketball. It is used mainly by players who are not tall enough to dunk the ball when open on a fast break as well as for players who are close to the basket with no opponents in their path. Learning how to shoot a basketball lay up is an efficient action for all basketball players and can help to make them all a better well rounded player. However there are many biomechanical principles involved in performing an efficient basketball lay up. In this blog I am going to explore the many biomechanical principles involved in a basketball lay up as well as giving you an idea how to perform or improve your basketball lay up skills.
 

Biomechanical Principles:

As mentioned there are a number of biomechanical principles involved in performing a basketball lay up. These include:

  • Momentum
  • Vertical Jump
  • Force
  • Mass
  • Inertia, and
  • Impulses

 

Momentum

Evidence in the basketball lay up:

  • This can be seen through the running movement towards the basketball ring.
Mo = MV [Momentum = Mass x Velocity]

Momentum is the amount of motion acquired by a moving body and is measured using the body’s mass and velocity. This implies that the larger the mass of an object, the greater it’s momentum will be. The velocity on the ball is the sum of the shooters speed and the balls speed (Flores, 2003).

A lay up varies from a regular shot in basketball because instead of using your arms to throw the ball at the basket you are laying the ball up on the backboard to help it go in. In this instance your body's momentum is a key factor to shooting an effective lay up. Certain aspects such as your height and speed will change your momentum. Making sure you gain enough speed during the run up is essential to gain momentum and performing a successful lay up, more importantly being able to transfer the momentum from running into the vertical jump.

It is suggested that you should start your run toward the basket between 5 and 10 feet from the low block on the lane. If the player is also on a 45˚ angle it is suggested that the lay up will have a higher successful rate.

 

Vertical Jump


Evidence in the basketball lay up:

  • This can be seen through players jumping when close to the ring to perform the lay up.

The vertical jump is a jumping ability in which an athlete can elevate himself or herself from a standing position in a vertically. In accordance with Newton’s third law whichever direction the player applies force there will be and opposite direction force applied back. Therefore in order to achieve a successful vertical jump the player must quickly applies force straight down to the ground, which the ground will cause a reaction that will propel them straight up. It is also essential to remember to keep your body straight and upright to maintain balance.

The vertical jump is an essential fundamental skill that most children learn at a young age and is an important factor in executing an effective basketball lay up. This is because it places you in the perfect position to be able to lay the ball. The body movement must also be transferred upward, instead of forward. To accomplish this, stretch out the last stride as the takeoff foot is planted and with the next step a shorter one, lift the jumping leg hard with the knee coming high as you can lift it. When shooting a lay up on the right side of the basket, you should make sure that your final step is your left foot and use it to step and then jump toward the basket, making sure you get as high up in the air as possible, Remembering to keep your body straight and upright. Jumping off the proper foot will give your body the right angle to the basket.

Note: A lay-up on the right side means your final step should be done off the left foot, while a lay-up on the left side should be done off the right foot.

 
 

Force


Evidence in the basketball lay up:

  • This can be seen through running, shooting
F=MA [Force = Mass x Acceleration]

Force is the “product of mass and acceleration; includes a change in the mobile state of an object” (Blazevich, 2010). As Newton’s Third Law states, every action has an equal and opposite reaction. Therefore in order to move in one direction you must apply force in the opposite direction. In this instance of a basketball lay up momentum is the most important factor however speed is also required. Speed requires a greater force applied in order to acquire a better result, although differences in the mass of the body will affect performance. You will also see evidence of Newton's third law when a player shoots or passes the ball.

The basketballs mass determines how much force a player must use when laying up. If a player uses too much or too little force applied to the ball, in relation to the ball's mass, the ball will not go where it is intended to go. Because the lay up is focused mainly on the height of the vertical jump opposed to other shooting styles there is less force required to achieve the intended outcome.

 
 

Mass


Evidence in the basketball lay up:

  • This can be seen through balance of running, jumping and landing.
Mass is the quantity of matter that makes up an object and has an effect most biomechanical processes for physical activity such as inertia and acceleration. The heavier you are the more stable you will be. Stability and balance helps to make sure that you have your mass centred in order to form a centre of gravity and is important when performing actions. In order to hold a steady balance you should hold your body weight directly above your base support. 

To perform a sufficient basketball lay up there are two masses you must consider this is first, the mass of the player and the second is the mass of the ball. The mass of the player is important as if you are aware of the players mass you can determine their centre of gravity. This will help with their balance and stability while running as well as how high they can jump in the vertical jump when force is applied. The mass of the ball however is also important when performing the lay up action because if too much force or not enough force is applied when laying the ball, the ball will not go where it was aimed.

 

Inertia


Evidence in the basketball lay up:

  • This can be seen through the vertical jump and laying up the ball with wrist.

Newton’s First law about inertia states an object will remain at rest or continue to move with constant velocity as long as the net force equals zero. This suggests that a body will continue in its state of rest or uniform motion unless acted upon by an applied force and that the greater the mass an object has the more inertia it has.

If no forces were present the ball would continue to travel in the direction it was aimed. Factors such as gravity acts upon the ball to pull it down to earth, the player then needs to judge the force of gravity and consider the weight of the ball to be able to find the path or line of trajectory so the ball will have the correct angle to fall into the basket.  


Impulse (Braking Impulse / Propulsive Impulse)


Evidence in the basketball lay up:

  • This can be seen through running, dribbling.
I = FT [Impulse = Force x Time]

 An impulse is the change of momentum that occurs when a force is applied to an object and is determined by the mass of the force applied to the object and the amount of time it is applied for.  Any change in momentum is equal to the impulse that produces it. Impulses have a strong relationship with momentum as the greater the applied impulse, the greater the increase in velocity.  If the breaking impulse (negative impulse) is less than the propulsive impulse (positive impulse), the players horizontal velocity is increased and if the breaking and propulsive impulse are both equal there is no change in the players velocity. However if the breaking impulse is greater than the propulsive impulse the players horizontal velocity is decreased.

Therefore in the run up the player will want to create lower breaking impulse and higher propulsive impulse as possible to increase the velocity and create a higher momentum. The impulse that a player delivers to the floor is also an indication of the player’s ability to jump.

 

Sub Questions


-          How would I overcome inertia to jump to greater heights?


In order to over come inertia a direct and large amount of force against the ground must be applied thus will then apply an equal and opposite force against the player. In order to produce forces to jump to greater heights we must first consider your mass and vertical forces. This is because the lower your mass the less gravity will affect the player and therefore less force you will need to produce. Optimising each of these areas will help in producing a successful vertical jump and therefore a more effective basketball lay up.

 -          How would I gain momentum to perform a more efficient basketball lay up?


Momentum is an essential factor in performing a basketball lay up. In order to increase the momentum of a player we must consider both mass and velocity. Both of these factors have the ability to increase momentum. If the mass of a player is increased, then their momentum will be too. The same can be said for velocity, as velocity increases the momentum will increase with it. Impulses are another contribution to increasing momentum.  This can be done by having the player produce more propulsive (positive) impulses in comparison to breaking (negative) impulses. Optimising these areas will help to gain more momentum and therefore create a more successful basketball lay up.

The Answer


There are many biomechanical principals involved in a basketball lay up, but regardless to knowing about them it is different to be able to execute in a game, this is because there will always be a slight change when performing this action. For example the momentum gained will vary depending on the length of your run up. The height of your vertical jump will change according to how much force you have applied and if it is applied straight down or with a slight angle. Your mass will change over time and therefore you will need to alter other areas to allow for this and finally the forces around you will constantly change due to environment and equipment. However if you remember the steps and think about the factors that contribute to perfecting the lay up then you will be able to develop and improve your skills.

Tips


Run up


1.       Gain as much momentum as possible as you run toward the basket.

2.       Produce higher propulsive impulses and lower breaking impulses

3.       Have a high mass, this will increase momentum

4.       Increase velocity.

5.       Be aware of centre of gravity for stability

Vertical Jump


1.       Take off on opposite leg [Left leg for right side lay up, Right Leg for Left Side Lay Up]

2.       Transfer the momentum into the vertical jump

3.       Create as much force straight down

4.       Having lower mass will increase vertical height

5.       Keep body upright

6.       Lift the knee of the same side your arm is raising, in order to keep balance

 Lay Up


1.       Transfer through the body into wrist

2.       Gently push or guide the ball towards the backboard [top corner]

3.       Be aware of angles and how the aim of the ball may change
 
 

 

How Else We Can Use This Information


This information can be used to determine how to coach a player to perform a more efficient basketball lay up. By observing a player you can establish where they are struggling and what areas they need to improve. For instance if a player is not jumping high enough you may want to consider the impulses and whether the player is applying all their force straight down to achieve the maximum height. You will also be able to determine the best angle to travel towards the basketball depending on the player’s form of laying up and where a player should aim on the backboard depending on the amount of force they use in their wrist to lay the ball up. Finally this information should be considered by all basketball players as different environments and equipment can change the outcome of the lay up, but having the knowledge and understanding how to change your form to still achieve an efficient lay up is the most important thing.

 

References

 
 
 
Blazevich, Anothony J. (2010). Sports Biomechanics The Basics Optimising Human Performance. London: Bloomsbury. 246, 2.
 
Wrisberg, C. A. (2007). Sport skill instruction for coaches. Champaign, IL: Human Kinetics. Ebooks available via HK. F796.07 W955s
 
Williams and Hodges (2004). Skill acquisition in sport. Routledge 796.01 S628
 
Flores, Darrick A. (2003).  The Physics of Basketball.
 
Burkett, G. (2010). Sports mechanics for coaches (3rd ed.). Champaign, IL: Human Kinetics. F612.76 C311
 
Bartlett (2007) Introduction to sports biomechanics. Routledge 612.76 B291i.2
 
Sandeep Kr. & Bhardwaj, B. (2011). Relationship among Selected Biomechanical Variables with Lay Up Shot Performance of Basketball Players. 229-233, 2. Accessed online at: ww.visualsoftindia.com/vsrd/vsrdindex.html