qualitative analysis of a vertical jump
Goals:
Biomechanical Factors of a Vertical Jump:
· Maximum height will be impacted by
o vertical velocity
o starting jump height
· Maximum time in the air to allow more height (happy medium)
· Person’s actual height and limb length
· Person’s ability to do work- ability to produce maximum force over a distance or vertical height in this case. This will be impacted by strength, flexibility, etc.
· Vertical height will be determined by the take off phase and the countermovement.
Takeoff phase:
· To maximize vertical velocity you need to cover the greatest distance as quick as possible. The countermovement will help the jumper achieve this.
· Starting height will have an impact on jump height; however, presumably most people will start on the floor.
· Countermovement is most important for maximum vertical force (In some cases, like a standing vertical jump, countermovements are not allowed. However, I wanted to investigate the forces for a countermovement as well.)
o ankle dorsiflexion to full ankle plantarflexion
o knee flexion to full knee extension
o hip flexion to full hip extension
o arm swing back to forward arm swing
· Arm swing is important for momentum and to raise the center of mass to propel the body upward.
· Angle of takeoff will impact height. If angled forward or backward at all you will propel your body horizontally as well. However, you only need vertical displacement.
· Gravity will be the largest counterforce; however, you need to overcome that counterforce and then produce the most additional force to achieve the best height.
· If the takeoff angle is not perpendicular to the floor, you will experience more friction forces from the ground. However, some friction is needed so you do not slip on takeoff. Surface and footwear should be considered.
· Takeoff needs to be off both feet to produce the most force. People may have a tendency to jump off one leg because they are focused on raising one side of their body more than the other.
Flight Phase:
· The countermovement during takeoff will determine maximum height before flight phase begins. The power produced during triple extension and the arm swing will propel the body upwards.
· Sequencing is also very important. Extension begins in the ankles, knees, and then hips, which starts the flight phase. If the sequencing is not correct, the force will not be maximized.
· Timing will also impact the flight phase. If the jumper pauses or does the countermovement too slow, it will not be as effective.
· The person’s ability to raise one arm as far as possible and hit the target will also be important. Once the arm swing is all the way forward the body needs to reorient to drive one arm up as high as possible. The maximum height of the arm raise must also occur at peak jump height. If they raise the arm too early it may slow down the jump and decrease max jump height. If they raise them too late, they won’t hit the highest marker possible.
Critical features to look for:
· Timing and quality of the countermovement
· Arm swing
· Angle of takeoff
· Triple extension and maximum extension
· Sequencing and timing of takeoff into flight
· Arm raise to hit the marker
· Take off from both legs
Observation Plan:
· Sagittal view for countermovement, arm swing, triple extension, sequencing and takeoff angle
· Frontal view for the arm raise to hit the marker and to make sure takeoff is from both legs
· Focus on countermovement and the takeoff; this will be the most important part.
- The main goal of a vertical jump is to achieve maximum height. Specifically, we want to hit the marker with one hand. Therefore, we need a maximum jump, while stretching one arm as high as possible. There is a little technical skill involved in the best way to hit the marker.
- Achieve the most power to propel ourselves vertically.
Biomechanical Factors of a Vertical Jump:
· Maximum height will be impacted by
o vertical velocity
o starting jump height
· Maximum time in the air to allow more height (happy medium)
· Person’s actual height and limb length
· Person’s ability to do work- ability to produce maximum force over a distance or vertical height in this case. This will be impacted by strength, flexibility, etc.
· Vertical height will be determined by the take off phase and the countermovement.
Takeoff phase:
· To maximize vertical velocity you need to cover the greatest distance as quick as possible. The countermovement will help the jumper achieve this.
· Starting height will have an impact on jump height; however, presumably most people will start on the floor.
· Countermovement is most important for maximum vertical force (In some cases, like a standing vertical jump, countermovements are not allowed. However, I wanted to investigate the forces for a countermovement as well.)
o ankle dorsiflexion to full ankle plantarflexion
o knee flexion to full knee extension
o hip flexion to full hip extension
o arm swing back to forward arm swing
· Arm swing is important for momentum and to raise the center of mass to propel the body upward.
· Angle of takeoff will impact height. If angled forward or backward at all you will propel your body horizontally as well. However, you only need vertical displacement.
· Gravity will be the largest counterforce; however, you need to overcome that counterforce and then produce the most additional force to achieve the best height.
· If the takeoff angle is not perpendicular to the floor, you will experience more friction forces from the ground. However, some friction is needed so you do not slip on takeoff. Surface and footwear should be considered.
· Takeoff needs to be off both feet to produce the most force. People may have a tendency to jump off one leg because they are focused on raising one side of their body more than the other.
Flight Phase:
· The countermovement during takeoff will determine maximum height before flight phase begins. The power produced during triple extension and the arm swing will propel the body upwards.
· Sequencing is also very important. Extension begins in the ankles, knees, and then hips, which starts the flight phase. If the sequencing is not correct, the force will not be maximized.
· Timing will also impact the flight phase. If the jumper pauses or does the countermovement too slow, it will not be as effective.
· The person’s ability to raise one arm as far as possible and hit the target will also be important. Once the arm swing is all the way forward the body needs to reorient to drive one arm up as high as possible. The maximum height of the arm raise must also occur at peak jump height. If they raise the arm too early it may slow down the jump and decrease max jump height. If they raise them too late, they won’t hit the highest marker possible.
Critical features to look for:
· Timing and quality of the countermovement
· Arm swing
· Angle of takeoff
· Triple extension and maximum extension
· Sequencing and timing of takeoff into flight
· Arm raise to hit the marker
· Take off from both legs
Observation Plan:
· Sagittal view for countermovement, arm swing, triple extension, sequencing and takeoff angle
· Frontal view for the arm raise to hit the marker and to make sure takeoff is from both legs
· Focus on countermovement and the takeoff; this will be the most important part.
vert_jump_checklist.docx | |
File Size: | 13 kb |
File Type: | docx |
Evaluation Plan:
· Use the “knowledge of results” technique for feedback
· Provide immediate feedback
· Give them quick and easy changes right away to their technique or form
· Develop a strength and power training program (like using the resistance cord shown below) if weaknesses are their biggest issue
· Use the “knowledge of results” technique for feedback
· Provide immediate feedback
· Give them quick and easy changes right away to their technique or form
· Develop a strength and power training program (like using the resistance cord shown below) if weaknesses are their biggest issue