The role of upper limb segment rotations in the development of racket‐head speed in the squash forehand

Abstract

In the squash forehand drive, the contribution that each of the upper limb segment's anatomical rotations make to racket‐head velocity towards the front wall (x‐direction) during the forward swing and at impact were calculated. Eight squash players (3 females, 5 males) capable of hitting a high‐performance squash forehand drive were filmed at a nominal rate of 300 Hz by two phase‐locked Photosonics cameras. The three‐dimensional displacement histories of 12 selected landmarks were then calculated using the direct linear transformation approach and three‐dimensional individual segment rotations were calculated using vector equations. Internal rotation of the upper arm at the shoulder joint (46.1%), hand flexion at the wrist joint (18.2%) and forearm pronation at the radio‐ulnar joint (12.0%) were the major contributors to the mean 30.8 m s^‐1 x‐direction velocity of the centre of the racket‐head at impact. Pronation of the forearm at the radio‐ulnar joint and extension at the elbow joint both played a significant role in generating racket velocity in the period prior to impact.

Keywords:

• Biomechanics
• forehand
• segment contributions
• squash