Objective Classification of Dynamic Balance Using a Single Wearable Sensor

William Johnston, Martin O'Reilly, Kara Dolan, Niamh Reid, Garrett F. Coughlan, Brian Caulfield


The Y Balance Test (YBT) is one of the most commonly used dynamic balance assessments in clinical and research settings. This study sought to investigate the ability of a single lumbar inertial measurement unit (IMU) to discriminate between the three YBT reach directions, and between pre and post-fatigue balance performance during the YBT. Fifteen subjects (age: 23±4, weight: 67.5±8, height: 175±8, BMI: 22±2) were fitted with a lumbar IMU. Three YBTs were performed on the dominant leg at 0, 10 and 20 minutes. A modified Wingate fatiguing intervention was conducted to introduce a balance deficit. This was followed immediately by three post-fatigue YBTs. Features were extracted from the IMU, and used to train and evaluate the random-forest classifiers. Reach direction classification achieved an accuracy of 97.80%, sensitivity of 97.86±0.89% and specificity of 98.90±0.56%. “Normal” and “abnormal” balance performance, as influenced by fatigue, was classified with an accuracy of 61.90%-71.43%, sensitivity of 61.90%-69.04% and specificity of 61.90%-78.57% depending on which reach direction was chosen. These results demonstrate that a single lumbar IMU is capable of accurately distinguishing between the different YBT reach directions and can classify between pre and post-fatigue balance with moderate levels of accuracy.


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Paper Citation

in Harvard Style

Johnston W., O'Reilly M., Dolan K., Reid N., F. Coughlan G. and Caulfield B. (2016). Objective Classification of Dynamic Balance Using a Single Wearable Sensor . In Proceedings of the 4th International Congress on Sport Sciences Research and Technology Support - Volume 1: icSPORTS, ISBN 978-989-758-205-9, pages 15-24. DOI: 10.5220/0006079400150024

in Bibtex Style

author={William Johnston and Martin O'Reilly and Kara Dolan and Niamh Reid and Garrett F. Coughlan and Brian Caulfield},
title={Objective Classification of Dynamic Balance Using a Single Wearable Sensor},
booktitle={Proceedings of the 4th International Congress on Sport Sciences Research and Technology Support - Volume 1: icSPORTS,},

in EndNote Style

JO - Proceedings of the 4th International Congress on Sport Sciences Research and Technology Support - Volume 1: icSPORTS,
TI - Objective Classification of Dynamic Balance Using a Single Wearable Sensor
SN - 978-989-758-205-9
AU - Johnston W.
AU - O'Reilly M.
AU - Dolan K.
AU - Reid N.
AU - F. Coughlan G.
AU - Caulfield B.
PY - 2016
SP - 15
EP - 24
DO - 10.5220/0006079400150024