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Related Experiment Video

Updated: Sep 23, 2025

A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
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Evaluation of two rotational helmet technologies to decrease peak rotational acceleration in cycling helmets.

Thomas Hoshizaki1,2, Andrew M Post3,4, Carlos E Zerpa5

  • 1Department of Kinesiology, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada. tbhoshiz@uwaterloo.ca.

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PubMed
Summary

Rotational management technologies in helmets reduce brain trauma risk. Both tested technologies lowered rotational acceleration and brain strain, but performance varied by impact type.

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Area of Science:

  • Biomechanics
  • Sports Engineering
  • Trauma Prevention

Background:

  • Brain trauma is linked to rotational kinematics.
  • Helmets with rotational management technologies aim to mitigate this risk.
  • Evaluating these technologies requires specific testing protocols.

Purpose of the Study:

  • To assess the effectiveness of two rotational management technologies in cycling helmets.
  • To compare a commercial technology with a novel, author-developed technology.
  • To analyze the dynamic response of the head form during impact.

Main Methods:

  • A rotation-specific test protocol was employed.
  • Three identical cycling helmets were tested: none, commercial technology, and novel technology.
  • Drop tests onto a 45° anvil measured head form dynamic response.

Main Results:

  • Both rotational helmet technologies reduced peak rotational acceleration.
  • Both technologies decreased brain strain compared to the control helmet.
  • Unique performance characteristics were observed for each technology based on impact conditions.

Conclusions:

  • Rotational management technologies are effective in reducing head injury biomechanics.
  • The choice of technology may influence effectiveness depending on the specific impact scenario.
  • Further research can refine helmet design for optimal rotational trauma mitigation.