The Influence of the Initiation of a Graded Exercise Protocol on Dynamic Postural Stability Following a Concussion

<p>Current post-concussion assessment tools may lack sensitivity in identifying recovery. Athletes demonstrating decreased postural control may have an increased likelihood of suffering sports-related injury. Exercise has been shown to briefly alter static postural control and the visual contribution to static postural stability deteriorates with moderate intensity exercise. Gait variability, defined as the fluctuation in gait characteristic between steps, is a sensitive measure of postural stability in populations with higher level gait disorders. Objective: The purpose of this study was to examine the influence of a progressive exertional return-to-play program on dynamic postural stability following a concussion. Design: Prospective longitudinal. Setting: Biomechanics laboratory. Participants: Nine participants (Height: 173.6±9.3, Weight: 85.7±24.7, Age: 19.4±1.3) who suffered sports-related concussions during intercollegiate athletic participation and nine physically active control participants (Height: 161.7±12.98, Weight: 77.3±19.98, Age: 22.8±1.99). Interventions: Both groups performed 10 trials of self-selected paced normal and fast gait along a 7.9m instrumented walkway. The concussion participants baseline testing was performed during pre-participation physicals prior to intercollegiate athletic participation. The second session was within 24 hours of suffering a concussion, the third session was the day before the exercise protocol began, and the remaining sessions were after the participant completed day one (stationary bike) and day two (elliptical) of the exercise protocol. Main Outcome Measures: Dependent variables of interest included step length variability, step width variability and step time variability. These values were expressed using a coefficient of variation [(standard deviation/mean)*100]. Dependent variables were compared with six 2x5 (group x day) repeated measures ANOVAs with a 0.01 adjusted alpha. Results: For normal speed, there was no group by time interaction (p=.526, p=.562, p=.271) or main effects for time (p=.925, p=.669, p=.808) for step length, step time, or step width variability across the testing days. A significant difference was found between the groups (p=.007) for normal speed step length variability (Concussion 3.26±0.93, Controls 2.48±0.37), but not for step time or step width (p=.027, p=.071). For fast speed, there was no group by time interaction (p=.518, p=.866, p=.780) or main effects for time (p=.087, p=.884, p=.033) for step length, step time, or step width variability across the testing days. No significant differences were found between the two groups (p=.384, p=.072, p=.597) for fast speed variability measures. Conclusions: The results of this study suggest that athletes suffering from sports-related concussion do not display altered gait variability compared to healthy controls, potentially indicating that otherwise healthy postconcussion student athletes have sufficient compensatory mechanisms and/or strategies to reduce gait variability upon initiating exercise. This finding is surprising as previous studies have identified dynamic postural stability insufficiencies post-concussion, suggesting a conservative gait strategy has been adopted.</p>

Name thesis:degree_name

Master of Science in Kinesiology (M.S.)

Level thesis:degree_level

Thesis (open access)

Discipline thesis:degree_discipline

Department of Health and Kinesiology

Year dc:date.available

2013

Author dc:creator

• Hunter, Lauryn

Contributors dc:contributor

• Barry Munkasy
• Barry Joyner

• ETD
• Concussion
• Postural stability
• Exercise
• Gait variability
• Return-to-play
• Kinesiology

Repository record dc:identifier

https://digitalcommons.georgiasouthern.edu/etd/36

OAI identifier oai:identifier

oai:digitalcommons.georgiasouthern.edu:etd-1036