Abstract
The assessment of trunk sway smoothness using an accelerometer sensor embedded in a smartphone could be a biomarker for tracking motor learning. This study aimed to determine the reliability of trunk sway smoothness and the effect of visual biofeedback of sway smoothness on motor learning in healthy people during unipedal stance training using an iPhone 5 measurement system. In the first experiment, trunk sway smoothness in the reliability group (n = 11) was assessed on two days, separated by one week. In the second, the biofeedback group (n = 12) and no-biofeedback group (n = 12) were compared during 7 days of unipedal stance test training and one more day of retention (without biofeedback). The intraclass correlation coefficient score 0.98 (0.93–0.99) showed that this method has excellent test–retest reliability. Based on the power law of practice, the biofeedback group showed greater improvement during training days (p = 0.003). Two-way mixed analysis of variance indicates a significant difference between groups (p < 0.001) and between days (p < 0.001), as well as significant interaction (p < 0.001). Post hoc analysis shows better performance in the biofeedback group from training days 2 and 7, as well as on the retention day (p < 0.001). Motor learning objectification through visual biofeedback of trunk sway smoothness enhances postural control learning and is useful and reliable for assessing motor learning.
Highlights
Motor learning is a set of internal processes associated with practice and experience that lead to relatively permanent changes in the capability to perform a skilled behaviour
Despite both groups showing an increment in performance over time, we found that the performance and learning of the biofeedback group differed substantially from those of the no-biofeedback group between days
These results indicate that visual biofeedback of trunk sway smoothness may be used as a biomarker parameter of motor learning during postural training
Summary
Motor learning is a set of internal processes associated with practice and experience that lead to relatively permanent changes in the capability to perform a skilled behaviour. This learning can be evaluated through the number of errors or successful/failed attempts during task execution and motor skills, such as postural control performance [1]. Postural control, defined as “the act of maintaining, achieving or restoring a state of balance during any posture or activity” [2], is essential for standing and walking independently in order to carry out many daily routine and sports activities [2,3]; this control is affected in older people and in several neurological and musculoskeletal diseases [4,5,6,7,8,9]. Unipedal stance is a common exercise to assess and improve postural control [5,13,14,15,16,17,18]. To progress in postural control exercises, adequate integration of sensory and motor inputs is necessary in order to learn correctly [23]. Understood as sensory information additional to inherent feedback, is a strategy used to reduce task errors, which is based on auditory, tactile or visual reinforcement stimuli [24,25]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call