Association Between Plantarflexion Torque Variability In Quiet Stance And During Force And Position Tasks

Author(s)

Magalhaes, Fernando Henrique ^{[1, 2, 3]} ; Mello, Emanuele Moraes ^{[1, 2]} ; Kohn, Andre Fabio ^{[1, 2]}

Affiliation

^[1] Univ Sao Paulo, Biomed Engn Lab, EPUSP, PTC, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Neurosci Program, EPUSP, PTC, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Sch Arts Sci & Humanities, EACH, Ave Arlindo Bettio 1000, BR-03828000 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: SOMATOSENSORY AND MOTOR RESEARCH; v. 36, n. 4, p. 241-248, OCT 2 2019.
• Web of Science Citations: 0

Abstract

This study examined the association between plantarflexion torque variability during quiet bipedal standing (QS) and during plantarflexion force- and position-matching tasks (FT and PT, respectively). In QS, participants stood still over a force plate, and the mean plantarflexion torque level exerted by each subject in QS (divided by 2 to give the torque due to a single leg) served as the target torque level for right leg FT and PT (performed with the participants seated with their right knee fully extended). During FT participants controlled the force level exerted by the foot against a rigid restraint, while during PT they controlled the angular position of the ankle when sustaining equivalent inertial loads. Standard deviation (SD) of plantarflexion torque was computed from torque signals acquired during periods with and without visual feedback. Significant correlations were found between plantarflexion torque variability in QS and FT (r?=?0.8615, p?r?=?0.8838, p?=?0.0003 for visual and no visual conditions, respectively) as well as between QS and PT (r?=?0.8046, p?=?0.003 and r?=?0.7332, p?=?0.0103 for visual and no visual conditions, respectively), regardless of vision availability. No significant differences were found between the correlations for Qs vs FT and QS vs PT (t(8)?=?0.4778, p?=?0.6455 and t(8)?=?1.6819, p?=?0.1310 for visual and no visual conditions, respectively), as assessed by ?Hotelling-Williams? tests for equality among dependent correlations. The results indicate that simple measurements of plantarflexion torque fluctuations during FT and PT may be used to estimate balance ability. From a practical standpoint, it is suggested that rehabilitation protocols designed to regain/improve balance function may be based on the performance of FTs or PTs executed in a seated position. (AU)

• FAPESP's process: 15/13096-1 - Neuromuscular adaptations associated with sports practice: effect of muscle fatigue on electromyographic parameters and on postural control
• Grantee: Fernando Henrique Magalhães
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/17193-0 - Behavioral, brain and reflex responses to mechanical and electrical stimuli to study proprioception and the spinal cord in humans
• Grantee: André Fábio Kohn
• Support Opportunities: Regular Research Grants