Smartwatch-Based Walking Metrics Estimation

Gait parameters are important health indicators of neurological control, musculoskeletal health and fall risk, but traditional analysis requires specialized laboratory equipment. While smartphone inertial measurement units (IMUs) enable estimation of gait metrics, their real-world use may be limited by inconsistent placement and user burden. With a fixed on-wrist placement, smartwatches offer a stable, convenient and continuous monitoring potential, but wrist-based sensing presents inherent challenges due to the indirect coupling between arm swing and leg movement. This paper introduces a novel multi-head deep learning model leveraging IMU signals from a consumer smartwatch, along with user height information to estimate a comprehensive suite of spatio-temporal walking metrics, including step length , gait speed, swing time, stance time, and double support time. Results from 250 participants across two countries demonstrate that the model achieves high validity (Pearson r > 0.7) and reliability (ICC > 0.7) for most gait metrics, comparable or exceeding leading smartphone-based approaches. This work, the largest in-lab, smartwatch-based gait study to date, highlights the feasibility of gait monitoring using ubiquitous consumer smartwatches.