Finger flexion does not contribute to ball speed in overarm throws

Area of Science:

• Biomechanics
• Sports Science
• Kinesiology

Background:

• Understanding the biomechanics of overarm throws is crucial for optimizing performance and preventing injuries in ball sports.
• The specific role of finger movements, particularly flexion, in generating ball speed during the release phase remains an area of investigation.

Purpose of the Study:

• To investigate whether finger flexion occurs before ball release in overarm throws by recreational players.
• To determine if finger flexion contributes to the generation of ball speed in this population.

Main Methods:

• Utilized the magnetic-field search-coil technique with high-speed data sampling (1000 Hz) for precise motion analysis.
• Recorded three-dimensional angular positions of the middle finger phalanges and hand during seated and standing overarm throws.
• Employed pressure-sensitive microswitches to identify distinct phases of ball release.

Main Results:

• Finger flexion was consistently absent before ball release in all tested conditions (seated/standing, varying speeds).
• Up to the point of release, fingers primarily exhibited extension, associated with the opening of the hand.
• Post-release, rapid finger flexion was observed, likely triggered by reactive forces.

Conclusions:

• Finger flexion does not contribute to ball speed generation in overarm throws by recreational ball players.
• The primary finger action before release is extension, with flexion occurring reactively after the ball is released.
• These findings refine our understanding of the terminal phase of the overarm throwing motion.