Numerical Model

Numerical Model

The Netball Shot

The Numerical Model is a form of Quantitative Analysis in which we can use to analyse technique and sports performance. Analysing the biomechanics of a technique in this way means that we can advise the athlete to make small changes to their form in order to improve performance and maximise efficiency. 

Using analytic software allows us to record a technique and by using a scaling factor we can obtain information such as distances and angles of the technique. This data can then be used to edit and improve the overall performance. 

 I chose to analyse, Angle of Elbow, Angle of Release and Height of Release for the netball shot in which my athlete was performing. 

 I used video analysis software, Kinovea in order to analyse my athlete performing a netball shot. in the above frame we can see the height of the athlete (1.71m) and the angle of the elbow as she is set to take a shot (103 Degrees). 

As the athlete sets to take the shot, the angle at the elbow slightly opens up to 113 Degrees showing that she doesn't maintain her original body position once she bends her knees in order to take the shot. Steele (1993) suggests that the ball should be release from directly above the head in order to perform a successful shot when shooting from close to the basket. The angle of 113 degrees means that the ball is positioned directly above the head of the shooter, on this basis it would be fair to suggest the this stage of the shot is currently being performed correctly. 

In the next frame, when the ball is being released, we can see that the angle of release is 133 degrees during this shot. From this frame we can look at the projectile motion of the ball, projectile motion is the motion of an object (Blazevich, 2010), in this case it is the ball. Steele (1993) implies that the average entry angle for a ball successfully going through a ring is 43 degrees and that when a shooter is close to the goal the projectile motion is 90 degrees vertical and 0 degrees horizontal. On this basis we can see that the athlete needs to edit the angle of release to a smaller angle in order to increase her successful shooting ratio. When the ball enters the ring at an angle of 90 degrees it has a much greater opening for entry compared to entering the ring at an angle of 30 degrees. Hay (1993) suggests that an angle of entry of 90 degrees provides a margin for error of +-10.5 yet when the angle of entry is 32 degrees there is a 0.0 margin for error. 

From this final frame i am able to analyse the height of release for this particular netball shot. from the video analysis i can see that the shot is released from 2.02m away from the ground. Hay (1993( published a statement that jump shots can be released from heights as low as 2.5m and set shots even lower. Although this particular height of release is slightly below the recommended value it is very difficult for the athlete to control. In the frame we can see that the knees and elbow are fully extended and the athlete may struggle to be able to release the ball any higher as in the first frame we see that she is only 1.71m in height."Release height can be influenced and improved by extension at the knees and at the elbow of the shooting arm" -  (Steele, 1993).  This evidence from Biomechnical Factors affecting Performance in Netball reinforces my point about the athlete being able to release the ball at a point any higher than is illustrated in the above frame as she has already fully extended the knees and legs. As a result, it would be difficult to suggest any coaching points in order to improve this section of the shooting sequence. 

References

  Blazevich, A. (2010). Sports biomechanics the basics: Optimising human performance. Bloomsbury: Black Publishing. 

Steele, J. ( 1993). Biomechanical factors affecting performance in netball. Department of Biomedical Science. 3, 1-18.

Hay, J (1993). The Biomechanics of Sports Techniques. USA: Prentice-Hall. 225-250.