Validation of a Markerless Multi-Camera Pipeline for Bouldering Fall Kinematics

Area of Science:

• Biomechanics
• Sports Science
• Motion Analysis

Background:

• Indoor bouldering leads to frequent lower-limb injuries due to falls from heights up to 5m.
• Understanding fall kinematics is crucial but challenging due to the impracticality of lab-based motion capture in gyms.

Purpose of the Study:

• To validate a markerless multi-camera motion analysis system (Pose2Sim) against established methods.
• To assess Pose2Sim's accuracy for measuring displacement and velocity during indoor bouldering falls.
• To compare Pose2Sim's acceleration measurements with those from inertial measurement units (IMUs).

Main Methods:

• Ten teenage climbers performed 40 falls, recorded using five high-speed cameras and three IMUs.
• Pose2Sim (markerless video analysis) was validated against Kinovea (2D video analysis) and IMUs.
• Data processing involved setting cut-off frequencies using Yu's method for both video and IMU data.

Main Results:

• Pose2Sim closely matched Kinovea for fall height and peak velocity, with no significant differences.
• Pose2Sim underestimated peak acceleration compared to IMUs.
• No significant difference in acceleration was found at the forehead, potentially due to lower impact forces.

Conclusions:

• Markerless video analysis (Pose2Sim) is suitable for studying indoor bouldering fall kinematics and typology.
• IMUs are essential for accurately quantifying impact intensity.
• Future research should integrate video analysis and IMUs to capture comprehensive fall data.