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Exploring the torque- velocity relationship in postmenopausal women: Analyzing the influence of data processing
Jessica Rial-Vázquez1, Alejandra Camacho-Villa1, Sonia Liliana Rivera-Mejía1
1Performance and Health Group, Department of Physical Education and Sport, Faculty of Sports Sciences and Physical Education, University of A Coruna, A Coruña, Spain.
Plos One
|June 30, 2025
Summary
This study found that different data processing methods (actual vs. target velocity) significantly impact torque-velocity (TV) relationship models in postmenopausal women. Quadratic polynomial models are recommended for fitting TV data in knee extensor and elbow flexor muscles.
Area of Science:
- Biomechanics
- Exercise Physiology
- Gerontology
Background:
- The torque-velocity (TV) relationship is crucial for understanding muscle function.
- Accurate modeling of the TV relationship is essential for assessing muscle strength, particularly in aging populations.
- Postmenopausal women may experience changes in muscle strength and performance that necessitate careful evaluation.
Purpose of the Study:
- To compare the goodness of fit and parameters of linear and non-linear models for the torque-velocity (TV) relationship in postmenopausal women.
- To investigate the influence of data processing methods (actual vs. target velocity data) on TV relationship modeling.
- To determine the optimal model for analyzing isokinetic strength data in this demographic.
Main Methods:
- Sixteen physically active postmenopausal women underwent isokinetic testing of knee extensors (KE) and elbow flexors (EF).
- Torque-velocity data were collected at various speeds (30-300°/s) using an isokinetic dynamometer.
- Data were fitted using linear, quadratic polynomial (PM), and Hill's (HM) models, analyzing both actual (TVA) and target (TVT) velocity data.
Main Results:
- Significant differences in goodness of fit and TV parameters were observed between TVA and TVT analyses for both KE and EF.
- For TVA, Hill's Model (HM) best fit KE, while Quadratic Polynomial (PM) best fit EF.
- Hill's Model (HM) produced unrealistic maximum velocity estimates for KE, highlighting potential model limitations.
Conclusions:
- Isokinetic assessments in postmenopausal women, especially at high velocities, require careful data examination.
- Actual velocity data (TVA) and target velocity data (TVT) should not be used interchangeably for TV relationship analysis.
- Quadratic polynomial models are recommended for fitting torque-velocity data in both knee extensors and elbow flexors for postmenopausal women.
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