Predicting vertical ground reaction force during running using novel piezoresponsive sensors and accelerometry

ABSTRACT

Running is a common exercise with numerous health benefits. Vertical ground reaction force (vGRF) influences running injury risk and running performance. Measurement of vGRF during running is now primarily constrained to a laboratory setting. The purpose of this study was to evaluate a new approach to measuring vGRF during running. This approach can be used outside of the laboratory and involves running shoes instrumented with novel piezoresponsive sensors and a standard accelerometer. Thirty-one individuals ran at three different speeds on a force-instrumented treadmill while wearing the instrumented running shoes. vGRF was predicted using data collected from the instrumented shoes, and predicted vGRF were compared to vGRF measured via the treadmill. Per cent error of the resulting predictions varied depending upon the predicted vGRF characteristic. Per cent error was relatively low for predicted vGRF impulse (2–7%), active peak vGRF (3–7%), and ground contact time (3–6%), but relatively high for predicted vGRF load rates (22–29%). These errors should decrease with future iterations of the instrumented shoes and collection of additional data from a more diverse sample. The novel technology described herein might become a feasible way to collect large amounts of vGRF data outside of the traditional biomechanics laboratory.

KEYWORDS:

• Wearables
• Gait
• biomechanics

Disclosure statement

Jake Merrell, Anton Bowden, and David Fullwood are listed inventors on the patent for the nanocomposite piezo-responsive foam (NCPF) sensors discussed in this paper. Jake Merrell is the majority owner of Nano Composite Products, which has licensed the patents related to the technology presented in this paper.

Additional information

Funding

This research was supported by the National Science Foundation: Agency Tracking #: 1538447 Project Title: Mobile Gait Analysis via Low-power Piezoresponsive Wearable Sensors Program Title: Dynamics, Control and System Diagnostics Program Code: 7569Funding Opportunity #: PD 14-7569