The effect of pretest exercise on baseline computerized neurocognitive test scores

Abstract

Background: Baseline neurocognitive assessment plays a critical role in return-to-play decision making following sport-related concussions. Prior studies have assessed the effect of a variety of modifying factors on neurocognitive baseline test scores. However, relatively little investigation has been conducted regarding the effect of pretest exercise on baseline testing. Purpose/Hypothesis: The aim of our investigation was to determine the effect of pretest exercise on baseline Immediate Post- Concussion Assessment and Cognitive Testing (ImPACT) scores in adolescent and young adult athletes. We hypothesized that athletes undergoing self-reported strenuous exercise within 3 hours of baseline testing would perform more poorly on neurocognitive metrics and would report a greater number of symptoms than those who had not completed such exercise. Study Design: Cross-sectional study; Level of evidence, 3. Methods: The ImPACT records of 18,245 adolescent and young adult athletes were retrospectively analyzed. After application of inclusion and exclusion criteria, participants were dichotomized into groups based on a positive (n 1/4 664) or negative (n 1/4 6609) selfreported history of strenuous exercise within 3 hours of the baseline test. Participants with a positive history of exercise were then randomly matched, based on age, sex, education level, concussion history, and hours of sleep prior to testing, on a 1:2 basis with individuals who had reported no pretest exercise. The baseline ImPACT composite scores of the 2 groups were then compared. Results: Significant differenceswere observed for the ImPACTcomposite scores of verbalmemory, visualmemory, reaction time, and impulse control as well as for the total symptom score. No significant between-group difference was detected for the visual motor composite score. Furthermore, pretest exercisewas associatedwith a significant increase inthe overall frequency of invalidtest results. Conclusion: Our results suggest a statistically significant difference in ImPACT composite scores between individuals who report strenuous exercise prior to baseline testing compared with those who do not. Since return-to-play decision making often involves documentation of return to neurocognitive baseline, the baseline test scores must be valid and accurate. As a result, we recommend standardization of baseline testing such that no strenuous exercise takes place 3 hours prior to test administration.