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Lower-extremity ground reaction forces in collegiate baseball pitchers
John A Guido1, Sherry L Werner
11Out-Patient Rehabilitation, Sports Medicine Division, Ochsner Health System, New Orleans, Louisiana, USA.
Journal of Strength and Conditioning Research
|February 21, 2012
Summary
Ground reaction forces (GRF) in baseball pitchers correlate with ball velocity. Braking forces are key to controlling descent, but shear forces may cause lower-extremity injuries in pitchers.
Area of Science:
- Biomechanics
- Sports Medicine
- Baseball Pitching Analysis
Background:
- Baseball pitching involves complex biomechanics.
- Understanding ground reaction forces (GRF) is crucial for injury prevention.
Purpose of the Study:
- Investigate ground reaction forces (GRF) in collegiate baseball pitchers.
- Examine the relationship between GRF and pitching mechanics.
Main Methods:
- Collected high-speed video and force plate data from 14 collegiate baseball pitchers.
- Analyzed fastball pitching mechanics and associated GRF.
Main Results:
- Peak braking GRF reached 245% body weight (BW), correlating with ball velocity.
- Maximum vertical GRF averaged 202% BW post-stride foot contact.
- Horizontal GRF peaked at 45% BW laterally.
Conclusions:
- Braking force is a significant factor in achieving high ball velocity.
- Pitching motion may generate shear forces, contributing to lower-extremity injuries in pitchers.
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