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Does Performance-Related Information Augment the Maximal Isometric Force in the Elbow Flexors?
William Miller1, Sunggun Jeon2,3, Minsoo Kang4
1Department of Health, Exercise Science, and Recreation Management, Neuromuscular Laboratory, The University of Mississippi, 243A Turner Center University, University, MS, 38677-1848, USA. wmmille2@olemiss.edu.
Feedback conditions significantly impact elbow flexor maximal voluntary isometric (MVIC) force. Visual feedback (VI), alone or combined with verbal encouragement (VE), enhances MVIC force compared to VE or no feedback (NOVIVE).
Area of Science:
- Exercise Physiology
- Biomechanics
- Motor Control
Background:
- Maximal voluntary isometric (MVIC) force measurement is crucial in various physical and rehabilitation contexts.
- The influence of different feedback modalities on force production requires further investigation.
Purpose of the Study:
- To examine the effects of visual feedback (VI), verbal encouragement (VE), and their combination (VIVE) on elbow flexor MVIC force.
- To analyze the impact of these feedback conditions on the rate of force development (RFD) and rate of electromyography rise (RER).
Main Methods:
- Twenty participants (10 males) performed three 5-s MVIC trials under four conditions: VI, VE, VIVE, and no feedback (NOVIVE).
- Repeated measures ANOVA analyzed MVIC force, RFD (0-200ms), and RER (0-200ms) across conditions and sexes.
- Electromyography (EMG) data were collected to assess muscle activation patterns.
Main Results:
- A significant main effect of condition was found for MVIC force, with VIVE and VI conditions yielding greater force than VE and NOVIVE.
- A significant sex × condition interaction was observed for RFD, with males showing greater RFD than females under VI condition.
- Males exhibited significantly higher RER compared to females across all conditions.
Conclusions:
- Visual feedback (VI), either alone or combined with verbal encouragement (VE), is important for accurately measuring elbow flexor MVIC.
- These findings provide a basis for optimizing feedback strategies in training and rehabilitation settings.
- Sex-based differences in muscle activation dynamics warrant consideration in feedback interventions.
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