Related Experiment Video
Updated: Sep 4, 2025
08:45
Assessment of Physical Activity Intensity with Accelerometers and Oxygen Consumption
Published on: June 20, 2025
167
Quantification of acceleration as activity counts in ActiGraph wearable.
Ali Neishabouri1, Joe Nguyen2, John Samuelsson2,3
1ActiGraph LLC, 49 East Chase St., Pensacola, FL, 32502, US. ali.neishabouri@theactigraph.com.
Scientific Reports
|July 13, 2022
Summary
This study details ActiGraph wearable accelerometer algorithms, enhancing data transparency for physical activity counts. This promotes comparability across studies and advances digital health applications.
Area of Science:
- Digital Health
- Wearable Technology
- Biomedical Engineering
Background:
- Wearable devices generate digital clinical measures used in trials and healthcare.
- Epoch-based physical activity counts from accelerometers are widely used but lack standardization.
- Proprietary algorithms hinder comparability and clinical application of wearable data.
Purpose of the Study:
- To provide transparent and detailed descriptions of ActiGraph's physical activity count algorithms.
- To publish the current algorithm as a standalone Python package for research accessibility.
- To improve data interpretability and interoperability in digital health research.
Main Methods:
- Detailed description of counts algorithms for five generations of ActiGraph devices (AM7164 model onwards).
- Publication of the current algorithm used in ActiLife and CentrePoint software.
- Development of a standalone Python package for the current algorithm.
Main Results:
- Comprehensive documentation of ActiGraph's historical and current physical activity count algorithms.
- Availability of a Python package for implementing the current algorithm.
- Increased transparency regarding the computation of physical activity data from ActiGraph devices.
Conclusions:
- Enhanced transparency of algorithms facilitates comparability and clinical applicability of wearable accelerometer data.
- The published algorithms and Python package serve as a valuable resource for the research community.
- This work accelerates digital health science and promotes wider clinical adoption of wearable accelerometry.
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