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Updated: Jun 21, 2026
06:21
Postural Organization of Gait Initiation for Biomechanical Analysis Using Force Platform Recordings
Published on: July 26, 2022
Estimation procedures affect the center of pressure frequency analysis
T M M Vieira1, L F Oliveira, J Nadal
1Laboratorio di Ingegneria del Sistema Neuromuscolare, Politecnico di Torino, Torino, TO, Italia.
Summary
Standardizing power spectrum estimation for body sway analysis is crucial for reliable clinical balance assessments. Even short test durations can yield dependable results with appropriate methods.
Area of Science:
- Biomechanics
- Clinical Physiology
- Signal Processing
Background:
- Frequency analysis of body sway is common in clinical balance studies.
- Current power spectrum estimation methods lack standardization, potentially leading to unreliable results.
- Accurate analysis of body sway is vital for understanding postural control.
Purpose of the Study:
- To investigate the impact of different power spectrum estimation methods on median frequency values.
- To assess the reliability of median frequency estimates for varying test durations.
- To propose a standardized approach for analyzing center of pressure (COP) spectral data.
Main Methods:
- Stabilometric tests were performed on 35 healthy adults.
- Power spectral density was estimated for anterior-posterior COP time series.
- Median frequency was compared across different signal partitioning, sampling rates, test durations, and detrending methods.
- Intraclass correlation coefficient (ICC) was used to assess reliability for different test durations.
Main Results:
- Increasing segments, shortening test duration, or applying linear detrending significantly increased median frequency (up to 137%).
- Short test durations (e.g., 20 seconds) demonstrated reliable estimates (ICC 0.74-0.89).
- Variations in methodology significantly affect COP median frequency values.
Conclusions:
- Standardized protocols for COP spectral analysis are needed for reliable clinical balance assessment.
- A balance between spectral resolution and variance is key for accurate analysis.
- The study proposes an algorithm for estimating COP power density spectrum.
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