Jump Spin Serve: Bio Mechanical Breakdown (4 step approach)
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Preliminary Movements: get ball, determine where you want the ball to go, ball is held in hitting hand sitting at hip level, non dominant foot is forwards. Ball is tossed high and in front of hitting arm, with backspin. As ball is released from your hands, medium step with dominant foot is taken.
Backswing Movements: footwork-Non dominant foot takes a medium step forwards, other foot takes a large step and increases the bend in the knee, non dominant takes a small step to close and jump Arm Swing- After ball is tossed, both arms are extended in the sagittal plane on the 2nd step, then rotated forwards on the third to be flexed and extended with the jump. Hitting arm is drawn back with a flexed, high elbow. Body-hips are externally rotated Force-Producing Movements: extension of the arm to hit the ball, internal rotation of the hips and core to generate torque Critical Instant: ball is contacted with an extended arm, body is in mid jump Follow Through: wrist is "snapped" or flexed, generating spin on the ball, landing from jump with bent knees |
7 Principles of BioMechanics
Stability:
Moments of Forced Instability-tossing the ball (leaning forwards), in jump, the body needs to generate torque by rotating the hips and the core, followed by the arm swing, very unstable moments. Centre of mass is not lowered, not very wide base of support and weight is not evenly distributed throughout the motions.
Maximun Effort:
Joints are being used to their full potential; hips, knee, ankle, shoulder, elbow and wrist. Power is generated by using these joints through full range of motion.
Maximum Velocity:
All Joints are being used from largest to smallest
Lower Body- hips, knee, ankle
Upper Body-hips, shoulder, elbow, wrist, fingers
Impulse:
the force applied to the ball for a greater time will generate more impulse, momentum and velocity.
Direction of Applied Force:
All force producing movements (steps, jump, swing) are oriented in the desired direction of travel (forward)
To vary direction of the ball, there are 2 options:
Production of Angular Motion (Torque):
Angular motion is produced by applying a force at a certain distance from an axis. When doing a jump top spin serve, the magnitude of the applied force is great and the arm is completely extended (lengthened lever arm) generating torque.
Conservation of Angular Momentum:
Angular momentum is the product of angular velocity (amount of rotations/time) and moment of inertia. Since the moment of inertia is the object's resistance to change in its rate of angular rotation or distribution of mass from the axis, the ball has a very small resistance due to its spherical shape. A good top spin serve will have a large angular velocity and so the angular momentum will be greater. When the ball is in the air, the angular momentum is constant.
Moments of Forced Instability-tossing the ball (leaning forwards), in jump, the body needs to generate torque by rotating the hips and the core, followed by the arm swing, very unstable moments. Centre of mass is not lowered, not very wide base of support and weight is not evenly distributed throughout the motions.
Maximun Effort:
Joints are being used to their full potential; hips, knee, ankle, shoulder, elbow and wrist. Power is generated by using these joints through full range of motion.
Maximum Velocity:
All Joints are being used from largest to smallest
Lower Body- hips, knee, ankle
Upper Body-hips, shoulder, elbow, wrist, fingers
Impulse:
the force applied to the ball for a greater time will generate more impulse, momentum and velocity.
Direction of Applied Force:
All force producing movements (steps, jump, swing) are oriented in the desired direction of travel (forward)
To vary direction of the ball, there are 2 options:
- Square hips up to desired position and start approach from there
- Rotate the wrist to finish and follow through pointing at desired direction or place
Production of Angular Motion (Torque):
Angular motion is produced by applying a force at a certain distance from an axis. When doing a jump top spin serve, the magnitude of the applied force is great and the arm is completely extended (lengthened lever arm) generating torque.
Conservation of Angular Momentum:
Angular momentum is the product of angular velocity (amount of rotations/time) and moment of inertia. Since the moment of inertia is the object's resistance to change in its rate of angular rotation or distribution of mass from the axis, the ball has a very small resistance due to its spherical shape. A good top spin serve will have a large angular velocity and so the angular momentum will be greater. When the ball is in the air, the angular momentum is constant.
Applications of Newton's Laws to the Sport of Volleyball
The Law of Inertia:
"Objects in motion tend to stay in motion unless acted upon by a net unbalanced force."
This law can be applied to any skill used in volleyball, but let's look at a pass and a hit. When a player return or passes a hit from the other side, the ball changes velocity and directions due to the force applied from the platform of the pass. This can also be said about a hit. If the hitter did not hit the set, the ball would continue in its parabolic motion, but since the player intercepts this path and applies a downward force, this parabolic motion is unbalanced and the result is a change in velocity and direction.
The Law of Acceleration:
"F=Ma"
The relationship between Force, mass and acceleration can describe the difference between different hitter's strength. Since the mass of the volleyball remains constant, the only variable that will impact the acceleration of the ball is the force applied. Therefore, the greater the force applied to the ball, the greater the acceleration and the harder the hit is to return.
The Law of Action-Reaction:
"For every action, there is an equal, but opposite reaction."
Let's look at a serve. When a player makes a good, hard serve with a large force applied to the ball, the ball applies the same force back to their hand, leaving it a little bit sore or red. This demonstrated Newton's Third Law very well. Your hand will sting or turn red because of this action-reaction force.
"Objects in motion tend to stay in motion unless acted upon by a net unbalanced force."
This law can be applied to any skill used in volleyball, but let's look at a pass and a hit. When a player return or passes a hit from the other side, the ball changes velocity and directions due to the force applied from the platform of the pass. This can also be said about a hit. If the hitter did not hit the set, the ball would continue in its parabolic motion, but since the player intercepts this path and applies a downward force, this parabolic motion is unbalanced and the result is a change in velocity and direction.
The Law of Acceleration:
"F=Ma"
The relationship between Force, mass and acceleration can describe the difference between different hitter's strength. Since the mass of the volleyball remains constant, the only variable that will impact the acceleration of the ball is the force applied. Therefore, the greater the force applied to the ball, the greater the acceleration and the harder the hit is to return.
The Law of Action-Reaction:
"For every action, there is an equal, but opposite reaction."
Let's look at a serve. When a player makes a good, hard serve with a large force applied to the ball, the ball applies the same force back to their hand, leaving it a little bit sore or red. This demonstrated Newton's Third Law very well. Your hand will sting or turn red because of this action-reaction force.