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Updated: Jul 15, 2026

Force and Position Control in Humans - The Role of Augmented Feedback
Published on: June 19, 2016
Aging, visuomotor correction, and force fluctuations in large muscles
Brian L Tracy1, Devin V Dinenno, Bjorn Jorgensen
1Department of Health and Exercise Science, Colorado State University, Fort Collins, CO 80523-1582, USA. tracybl@cahs.colostate.edu
Visuomotor correction significantly impacts force fluctuations in elderly adults, especially at lower muscle forces. These visual feedback processes contribute to age-related increases in force variability.
Area of Science:
- Neuroscience
- Human Physiology
- Aging Research
Background:
- Aging is associated with declines in motor control and increased force fluctuations.
- Visuomotor feedback plays a crucial role in maintaining stable muscle force output.
Purpose of the Study:
- To quantify the contribution of visuomotor correction to force fluctuations in elderly adults.
- To compare visuomotor correction effects on elbow flexor and knee extensor muscles between young and elderly adults.
Main Methods:
- Young and elderly adults performed constant-force contractions at various target forces (2.5%, 30%, 65% MVC) with and without visual feedback.
- Force fluctuations were quantified using standard deviation (SD) and coefficient of variation (CV) of force.
- Power spectrum analysis was used to assess frequency-dependent changes in force fluctuations.
Main Results:
- Elderly adults exhibited lower maximal voluntary contraction (MVC) force.
- The coefficient of variation (CV) of force was higher with visual feedback, particularly at low target forces (2.5% MVC) in elderly adults.
- Age-related differences in force fluctuation power spectra were observed in elbow flexors.
Conclusions:
- Visuomotor correction contributes to force fluctuations in large proximal muscles.
- This contribution is more pronounced in healthy elderly adults at low force levels.
- Visuomotor processes are implicated in the age-related increase in force fluctuations.
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