Objective Assessment of Physical Activity at Home Using a Novel Floor-Vibration Monitoring System: Validation and Comparison With Wearable Activity Trackers and Indirect Calorimetry Measurements

Yuki Nakajima; Asami Kitayama; Yuji Ohta; Nobuhisa Motooka; Mayumi Kuno-Mizumura; Motohiko Miyachi; Shigeho Tanaka; Kazuko Ishikawa-Takata; Julien Tripette

doi:10.2196/51874

Objective Assessment of Physical Activity at Home Using a Novel Floor-Vibration Monitoring System: Validation and Comparison With Wearable Activity Trackers and Indirect Calorimetry Measurements

JMIR Form Res. 2024 Apr 25:8:e51874. doi: 10.2196/51874.

Authors

Yuki Nakajima^#¹, Asami Kitayama^#¹, Yuji Ohta¹, Nobuhisa Motooka¹, Mayumi Kuno-Mizumura², Motohiko Miyachi^{3

4}, Shigeho Tanaka^{4

5}, Kazuko Ishikawa-Takata^{4

6}, Julien Tripette^{1

4

7}

Affiliations

¹ Department of Human-Environmental Sciences, Ochanomizu University, Bunkyo, Japan.
² Department of Performing Arts, Ochanomizu University, Bunkyo, Japan.
³ Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan.
⁴ National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Settsu, Japan.
⁵ Faculty of Nutrition, Kagawa Nutrition University, Sakado, Japan.
⁶ Faculty of Applied Biosciences, Tokyo University of Agriculture, Setagaya, Japan.
⁷ Center for Interdisciplinary AI and Data Science, Ochanomizu University, Bunkyo, Japan.

^# Contributed equally.

PMID: 38662415
DOI: 10.2196/51874

Abstract

Background: The self-monitoring of physical activity is an effective strategy for promoting active lifestyles. However, accurately assessing physical activity remains challenging in certain situations. This study evaluates a novel floor-vibration monitoring system to quantify housework-related physical activity.

Objective: This study aims to assess the validity of step-count and physical behavior intensity predictions of a novel floor-vibration monitoring system in comparison with the actual number of steps and indirect calorimetry measurements. The accuracy of the predictions is also compared with that of research-grade devices (ActiGraph GT9X).

Methods: The Ocha-House, located in Tokyo, serves as an independent experimental facility equipped with high-sensitivity accelerometers installed on the floor to monitor vibrations. Dedicated data processing software was developed to analyze floor-vibration signals and calculate 3 quantitative indices: floor-vibration quantity, step count, and moving distance. In total, 10 participants performed 4 different housework-related activities, wearing ActiGraph GT9X monitors on both the waist and wrist for 6 minutes each. Concurrently, floor-vibration data were collected, and the energy expenditure was measured using the Douglas bag method to determine the actual intensity of activities.

Results: Significant correlations (P<.001) were found between the quantity of floor vibrations, the estimated step count, the estimated moving distance, and the actual activity intensities. The step-count parameter extracted from the floor-vibration signal emerged as the most robust predictor (r²=0.82; P<.001). Multiple regression models incorporating several floor-vibration-extracted parameters showed a strong association with actual activity intensities (r²=0.88; P<.001). Both the step-count and intensity predictions made by the floor-vibration monitoring system exhibited greater accuracy than those of the ActiGraph monitor.

Conclusions: Floor-vibration monitoring systems seem able to produce valid quantitative assessments of physical activity for selected housework-related activities. In the future, connected smart home systems that integrate this type of technology could be used to perform continuous and accurate evaluations of physical behaviors throughout the day.

Keywords: activity tracker; floor vibration; home-based activity; housework-related activity; mobile phone; physical activity; physical behavior; smart home system.

©Yuki Nakajima, Asami Kitayama, Yuji Ohta, Nobuhisa Motooka, Mayumi Kuno-Mizumura, Motohiko Miyachi, Shigeho Tanaka, Kazuko Ishikawa-Takata, Julien Tripette. Originally published in JMIR Formative Research (https://formative.jmir.org), 25.04.2024.