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Nonlinear Dynamics Analysis of Handgrip Strength Using the Poincaré Plot Method Through Video Processing Techniques.
Constantin Ciucurel1, Elena Ioana Iconaru1
1Department of Medical Assistance and Physical Therapy, University Center of Pitesti, National University of Science and Technology Politehnica Bucharest, 110040 Pitesti, Romania.
Journal of Functional Morphology and Kinesiology
|November 25, 2024
Summary
This study shows that video analysis reliably measures handgrip strength (HGS) and that nonlinear dynamics, assessed via Poincaré plots, reveal insights into neuromuscular function and fatigue in young adults.
Area of Science:
- Biomechanics
- Human Physiology
- Neuromuscular Function
Background:
- Handgrip strength (HGS) is a key indicator of neuromuscular function.
- Understanding the nonlinear dynamics of HGS is crucial for assessing fatigue and performance.
- Previous methods for HGS analysis lacked detailed insights into short- and long-term variability.
Purpose of the Study:
- To analyze the nonlinear dynamics of handgrip strength (HGS) in young adults.
- To investigate the influence of hand dominance on HGS variability.
- To validate a video-based motion capture method for assessing HGS using Poincaré plot analysis.
Main Methods:
- A cross-sectional study involving 30 healthy young adults.
- Handgrip strength (HGS) measured using a hydraulic dynamometer and video motion capture (GoPro HERO11 Black).
- Poincaré plot analysis computed short-term (SD1) and long-term (SD2) variability indices from sustained isometric contractions.
Main Results:
- Strong correlation (p ≤ 0.001) confirmed the reliability of video measurements against mechanical dynamometry.
- Significant correlations (p ≤ 0.001) found among HGS, angular velocity, Poincaré indices, and fatigue levels.
- Higher maximum HGS and angular velocity correlated with increased nonlinear variability in force production.
Conclusions:
- The proposed video-based HGS assessment method is reliable.
- Poincaré plot analysis effectively captures nonlinear variability in HGS, offering insights into neuromuscular control and fatigue.
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