Medicine & Science in Sports & Exercise:
May 2006 - Volume 38 - Issue 5 - p S2
Presidential Closing Remarks 12:05 PM - 12:15 PM: Immediately Following President's Lectures ROOM: Ballroom 2/3 and Ballroom 1: A-14 Free Communication/Slide - Abnormal Gait WEDNESDAY, MAY 31, 2006 9:30 AM - 11:30 AM ROOM: 301
Research on the effect of concussion has largely focused on athletes and their responses to neuropsychological tests and static postural control. However, little is known about the effect of concussion on dynamic motor function and the extent to which athletes and non-athletes differ on tests of gait stability.
PURPOSE: The purpose of this study was to examine the effect of concussion on a dynamic motor task under conditions of divided and undivided attention in athletes and non-athletes.
METHODS: Twenty-two NCAA Division 1 and University Club Sports athletes and 15 non-athlete college students (no regular physical activities) with Grade 2 concussions were observed while walking under two conditions: 1) undivided attention (single-task) and 2) while simultaneously completing simple mental tasks (dual-task). Testing began within 48 hours of injury (day 2) and was repeated at 5, 14, and 28 days post injury. Whole-body motion data were collected using an eight-camera motion analysis system and two force plates to examine anterior and medial-lateral center of mass (COM) motion (ANTdisp, MLdisp), the peak anterior velocity of the COM (ANTvel), and the maximum separation between the COM and center of pressure (COP) (ANTmax). All variables were normalized to height. Three-way repeated-measures mixed design ANO VA and Tukey post hoc tests were completed to determine differences between group, task, and testing day (p <.05).
RESULTS: There were significant day by task interactions for ANTdisp (p <.006), MLdisp (p <.033), ANTvel (p <.003), and ANTmax (p <.031). Group differences were discovered for ANTdisp (p <.039), ANTvel (p <.000), and ANTmax (p <.003) with non-athletes exhibiting greater values than athletes for all variables. Follow-up analyses revealed significantly less ANTdisp, ANTvel, and ANTmax in the dual-task compared to single-task for athletes on all 4 testing days. For the non-athletes, ANTdisp and ANTmax were significantly less during the dual-task condition compared to the single-task for the first 3 testing sessions and on all days for ANTvel. MLdisp was greater on the dual-task than the single-task for days 2 and 5 in the athlete group.
CONCLUSION: Task complexity affects concussed athletes to greater extent than non-athletes and these effects last up to 4 weeks post-injury.