Related Experiment Video
Updated: Jul 3, 2026

07:24
A Method for Quantifying Upper Limb Performance in Daily Life Using Accelerometers
Published on: April 21, 2017
Comparing the performance of three generations of ActiGraph accelerometers
Megan P Rothney1, Gregory A Apker, Yanna Song
1Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA. rothneym@niddk.nih.gov
Journal of Applied Physiology (Bethesda, Md. : 1985)
|July 19, 2008
Summary
This study compared three ActiGraph accelerometer generations, finding the GT1M reduced inter-monitor variability but decreased sensitivity for light physical activity. Algorithms for energy expenditure may need updates for the GT1M model.
Area of Science:
- Biomedical Engineering
- Physical Activity Measurement
- Wearable Technology
Background:
- ActiGraph accelerometers are crucial for objective physical activity assessment in research.
- Consistency across different ActiGraph generations is not well-established.
- Understanding generational differences is vital for data comparability.
Purpose of the Study:
- To evaluate the dynamic response and inter-monitor variability of three ActiGraph accelerometer generations (7164, 71256, GT1M).
- To identify measurement differences impacting physical activity data across devices.
- To inform the use of historical and current ActiGraph data.
Main Methods:
- Utilized mechanical oscillations to test accelerometer response across varying radii and frequencies.
- Quantified inter-monitor variability within each of the three ActiGraph generations.
- Compared the dynamic response characteristics and measurement consistency between models.
Main Results:
- The GT1M showed significantly different activity count-radius relationships compared to older models (7164, 71256).
- All generations exhibited non-linear frequency responses, with significant inter-generational differences at certain frequencies.
- The GT1M demonstrated markedly reduced inter-monitor variability but decreased sensitivity in low-frequency detection.
Conclusions:
- The GT1M offers improved inter-monitor consistency but may be less suitable for monitoring sedentary or light-intensity movements.
- Existing energy expenditure prediction algorithms developed on older ActiGraph models may require recalibration for the GT1M.
- Careful consideration of generational differences is necessary when analyzing physical activity data from multiple ActiGraph models.
Related Concept Videos
Measuring Acceleration Due to Gravity
Consider a coffee mug hanging on a hook in a pantry. If the mug gets knocked, it oscillates back and forth like a pendulum until the oscillations die out.
A simple pendulum can be described as a point mass and a string. Meanwhile, a physical pendulum is any object whose oscillations are similar to a simple pendulum, but cannot be modeled as a point mass on a string because its mass is distributed over a larger area. The behavior of a physical pendulum can be modeled using the principles of...
A simple pendulum can be described as a point mass and a string. Meanwhile, a physical pendulum is any object whose oscillations are similar to a simple pendulum, but cannot be modeled as a point mass on a string because its mass is distributed over a larger area. The behavior of a physical pendulum can be modeled using the principles of...
Relative Motion Analysis - Acceleration
A slider-crank mechanism converts rotational motion from the crank into linear motion of the slider or vice versa. This mechanism consists of three main parts: the crank, the connecting rod, and the slider. The movement of the slider-crank is an example of general plane motion as the fluctuating angle between the crank and the connecting rod. Consider a segment AB where point A is at the end of the slider and point B is on the diametrically opposite end to point A, on a crack. The variance in...
