Methods for Evaluating Tibial Accelerations and Spatiotemporal Gait Parameters during Unsupervised Outdoor Movement.

Area of Science:

• Biomechanics
• Human Movement Science
• Geospatial Analysis

Background:

• Accurate measurement of gait and physiological responses during physical activity is crucial for understanding human performance and injury risk.
• Integrating environmental factors like terrain is essential for ecological validity in human movement studies.
• Existing methods often require complex synchronization or are limited in scalability for large-scale field studies.

Purpose of the Study:

• To introduce a novel, streamlined method for measuring spatiotemporal gait patterns, tibial accelerations, and heart rate.
• To synchronize these physiological and kinematic measures with high-resolution geographical terrain features.
• To demonstrate the method's efficacy using publicly available data from a large cohort during loaded ruck marches.

Main Methods:

• Utilized inertial measurement units (IMUs) and GPS watches on 218 participants during outdoor ruck hikes.
• Developed custom code for sensor data synchronization, IMU calibration, and gait phase detection (walking/running).
• Georeferenced GPS data with Geographic Information System (GIS) maps to extract terrain variables (slope, altitude, surface conditions).

Main Results:

• Successfully synchronized high-resolution gait, acceleration, and heart rate data with detailed terrain features.
• Demonstrated automated data processing for efficient analysis of large datasets.
• Validated the method's applicability across diverse terrain conditions and loaded conditions.

Conclusions:

• The presented method offers a practical and scalable approach for collecting detailed biomechanical and physiological data during real-world activities.
• This methodology facilitates the analysis of how terrain influences human locomotion and performance.
• The approach is adaptable to various populations and ground-based activities, including skiing and trail running.