Date of Award

January 2013

Degree Type

Open Access Thesis

Degree Name

Master of Science (MS)


Exercise and Sport Science

First Advisor

Matthew J. Sabin

Department Affiliation

Exercise and Sport Science


CONTEXT: Concussions are a major concern in sport and healthcare professionals are recognizing its profoundness in the impact it has on athletes. There may be limitations in the current approach to assessments among each individual evaluation involved; however, the combination of all three assessments adds to its strength and determining the overall understanding of the concussion and its effects. Any measure of assessment that connects underlying issues arising from concussion to help decrease long-term impairments by returning to play prematurely, risking further injury, is essential. The need for a dual-task assessment delivers an increased sensitivity to the assessment by combining two tasks forcing the individual to divide their attention. It is also important to determine if fatigue is a factor on the ability to complete a dual-task, the same way in which an individual would be asked to do during sport performance while fatigued. OBJECTIVE: The purpose is to evaluate the effect of fatigue on a dual-task postural control measure. DESIGN: Repeated measures. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: Sixty healthy, collegiate males and females (30 experimental 21.03±1.92 yrs., 30 control 20.70±1.93 yrs.) performed a dual-task balance test (Quick-Tap Concussion Assessment Protocol [QT-CAP]) at three specific times (baseline(T1), post-fatigue intervention(T2) and post-recovery(T3)). All participants took visual cues from a computer and were asked to respond by reaching with a specific leg to touch in a specific direction. INTERVENTION: Anthropometric measures were taken before all testing and other measures of performance, such as heart rate, rating of perceived exertion and vertical jump, were measured at each time. Testing was completed during one test session. Baseline (T1) testing on the QT-CAP protocol was completed followed by the experimental group participating in the fatigue protocol while the control group rested for ten minutes between T1 and T2. Post-fatigue intervention (T2) followed the fatigue protocol and the ten minute rest period for both groups. Both groups rested for an additional 15 minutes and then completed T3 testing. The fatigue protocol included completion of the PACER test until self-reported, complete exhaustion. MAIN OUTCOME MEASURES: Height, weight and age were used as descriptives to determine any differences between groups. Heart rate, RPE and vertical jump were used to determine level of fatigue within each individual. The QT-CAP protocol measures error scores in each group across three different time points. RESULTS: During T1 and T2, the control group had a significant increase in their QT-CAP scores (T1: 27.60 ±2.90; T2: 29.52 ± 4.29). The experimental group showed no significant increase in their QT-CAP scores (T1: 28.77 ± 2.90; T2: 28.93 ± 3.40), which could be due to the fatigue protocol. The experimental group had the opposite effect from T2-T3 and did show an increase in the QT-CAP scores (T2: 28.93 ±3.40; T3: 30.37 ± 2.06). The control group did not show any significant increase from T2-T3 on the QT-CAP (T2: 29.53 ± 4.29; T3: 29.87 ± 2.26). CONCLUSION: The control group showed an initial increase in their QT-CAP scores, showing a potential learning effect on the dual-task measure and then had less of an increase in their QT-CAP scores during T3. The experimental group showed a decreased learning effect after the fatigue protocol which helps to explain that fatigue does have an effect on the dual-task postural control measure. Following their 15 minute rest, an increase in QT-CAP scores shows the learning effect in the experimental group.