Getting in shape: Reconstructing three-dimensional long-track speed skating kinematics by comparing several body pose...

Area of Science:

• Biomechanics
• Sports Science
• Human Movement Analysis

Background:

• Body pose reconstruction (BPR) is vital in gait studies, but specific protocols for speed skating are lacking.
• The unique posture and technique in speed skating necessitate tailored BPR and inverse dynamics methods.
• Existing BPR techniques may not directly translate to the kinematic data of speed skating.

Purpose of the Study:

• To establish the optimal procedure for body pose reconstruction (BPR) in speed skating.
• To determine the best inverse dynamics approach for speed skating analysis.
• To quantify the influence of chosen BPR and inverse dynamics methods on joint power estimation.

Main Methods:

• An eight-body segment model was evaluated.
• Global optimization with revolute knee and lumbosacral joints, and spherical other joints was tested for inverse kinematics.
• A least-squares error method was compared with bottom-up approaches for inverse dynamics.

Main Results:

• The eight-body segment model with specific joint constraints is recommended for speed skating inverse kinematics.
• Combining this model with a least-squares error method for inverse dynamics is advised for joint power calculation.
• Failure to use optimization in BPR led to up to 74% underestimation of mean joint power.
• Using a bottom-up inverse dynamics method caused up to 31% underestimation of mean joint power.

Conclusions:

• Standardized reporting of BPR and inverse dynamics methods is essential for comparing human movement studies.
• The proposed methodology provides a more accurate estimation of joint power in speed skating.
• Establishing a golden standard for these analyses will enhance the reliability and comparability of research across human movement disciplines.