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A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
Published on: September 21, 2017
Simple strategy to prevent severe head trauma in Judo
Haruo Murayama1, Masahito Hitosugi, Yasuki Motozawa
1Department of Sports Science, Dokkyo Medical University School of Medicine.
Neurologia Medico-Chirurgica
|September 27, 2013
Summary
Adding an under-mat significantly reduces head impact forces in Judo, measured by the head injury criterion (HIC). This safety enhancement maintains Judo
Area of Science:
- Sports Science
- Biomechanics
- Injury Prevention
Background:
- Judo involves dynamic throws and potential head impacts.
- Assessing head injury risks is crucial for athlete safety.
- Standard tatami mats may not fully mitigate impact forces.
Purpose of the Study:
- To investigate the effect of an under-mat on head impact forces during Judo throws.
- To quantify changes in head acceleration and head injury criterion (HIC) values.
Main Methods:
- An anthropomorphic test device was used in Judo throws (Osoto-gari, Ouchi-gari).
- Impacts were conducted on a standard tatami with and without an added under-mat.
- Head acceleration was measured to calculate HIC values.
Main Results:
- The use of an under-mat significantly decreased HIC values in both Ouchi-gari and Osoto-gari techniques.
- HIC values reduced from 1174.7 to 539.3 for Ouchi-gari and 330.0 to 156.1 for Osoto-gari.
- The under-mat demonstrated a clear reduction in impact forces to the head.
Conclusions:
- An under-mat is an effective method for reducing head impact forces in Judo.
- Current safety measures are adequate, and rule changes are not required.
- The addition of an under-mat enhances safety without compromising the enjoyment or health benefits of Judo.
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