Differences in motor variability among individuals performing a standardized short-cycle manual task
2017 (English)In: Human Movement Science, ISSN 0167-9457, E-ISSN 1872-7646, Vol. 51, 17-26 p.Article in journal (Refereed) Published
Motor variability (MV) has been suggested to be a determinant of the risk for developing musculoskeletal disorders in repetitive work. In this study we examined whether individuals consistently differed in the extent of motor variability when performing a standardized short-cycle manual task. On three separate days, arm kinematics was recorded in 14 healthy subjects performing a pipetting task, transferring liquid from a pick-up tube to eight target tubes with a cycle time of 2.8 s. Cycle-to-cycle standard deviations (SD) of a large selection of shoulder and elbow kinematic variables, were processed using principal component analysis (PCA). Thereafter, between-subjects and between-days (within-subject) variance components were calculated using a random effects model for each of four extracted principal components. The results showed that MV differed consistently between subjects (95% confidence intervals of the between-subjects variances did not include zero) and that subjects differed consistently in MV between days. Thus, our results support the notion that MV may be a consistent personal trait, even though further research is needed to verify whether individuals rank consistently in MV even across tasks. If so, MV may be a candidate determinant of the risk of developing fatigue and musculoskeletal disorders in repetitive occupational work. (C) 2016 Elsevier B.V. All rights reserved.
Place, publisher, year, edition, pages
2017. Vol. 51, 17-26 p.
Kinematics, Repetitive task, Principal component analysis, Day-to-day variability, Between-subjects riability, Individual differences
IdentifiersURN: urn:nbn:se:umu:diva-132641DOI: 10.1016/j.humov.2016.10.009ISI: 000393633800003PubMedID: 27821310OAI: oai:DiVA.org:umu-132641DiVA: diva2:1082979