Postural sway and joint kinematics during quiet standing are affected by lumbar extensor fatigue.
Authors
Madigan-ML; Davidson-BS; Nussbaum-MA
Source
Hum Mov Sci 2006 Dec; 25(6):788-799
Abstract
The purpose of this study was to investigate changes in postural sway and strategy elicited by lumbar extensor muscle fatigue. Specifically, changes in center of mass (COM), center of pressure (COP), and joint kinematics during quiet standing were determined, as well as selected cross correlations between these variables that are indicative of movement strategy. Twelve healthy male participants stood quietly both before and after exercises that fatigued the lumbar extensors. Whole-body movement and ground reaction force data were recorded and used to calculate mean body posture and variability of COM, COP, and joint kinematics during quiet standing. Three main findings emerged. First, participants adopted a slight forward lean post-fatigue as evidenced by an anterior shift of the COM and COP. Second, post-fatigue increases in joint angle variability were observed at multiple joints including joints distal to the fatigued musculature. Despite these increases, anterior-posterior (AP) ankle angle correlated well with AP COM position, suggesting the body still behaved similar to an inverted pendulum. Third, global measures of sway based on COM and COP were not necessarily indicative of changes in individual joint kinematics. Thus, in trying to advance our understanding of how localized fatigue affects movement patterns and the postural control system, it appears that joint kinematics and/or multivariate measures of postural sway are necessary.
Keywords
Fatigue; Muscles; Motion-studies; Posture; Injuries; Musculoskeletal-system; Muscle-function; Muscle-physiology; Muscles;
Author Keywords: Muscle fatigue; Postural balance; Biomechanics
Contact
Department of Mechanical Engineering, Virginia Polytechnic Institute and State University, Mail Code 0238, Blacksburg, VA 24061
Document Type
Journal Article
Identifying No.
Grant-Number-R01-OH-007882
Source Name
Human Movement Science
Performing Organization
Virginia Polytechnic Institute and State University
