Effect of Time after COVID on Standing Postural Control

Abstract

This study investigated whether individuals exhibited changes in standing postural control following diagnosis of COVID infection and monitored the extent of alterations during multiple sessions over a 12 week period. Twenty post-COVID recovering individuals participated in three testing sessions. Center of pressure (COP) was recorded with a force plate while participants stood in a quiet posture and also while engaged in relatively low-level tasks representing activities expected to challenge posture. Participants quit a testing session if standing or the tasks became too difficult. Standard COP measures (path, RMS, path velocity and power spectrum in low and high frequency ranges) were calculated and task and session test times were recorded. Even 12 weeks post-COVID, some individuals were able to endure the complete test by completing all tasks, while others exhibited decreased endurance as they were unable to complete all tasks and stand for the duration of a session. For later test sessions, endurance was increased, as more participants were able to complete the tasks and stand for a greater time. However, the greater endurance demonstrated by these individuals was acquired at a cost of decreased postural control as indicated by increased postural oscillations. Results suggest that a 12 week post-COVID recovery period may not be sufficient to fully regain postural control. Improvements in postural endurance could be just compensatory reactions of postural control.