Does an Individual’s
Fitness Level Affect Baseline Concussion Symptoms?

Mrazik, M; Naidu, D; Lebrun, C; Game, A; Matthews-White, J. Journal
of Athletic Training In-Press. doi: 10.4085/1062-6050-48.3.19

Take Home Message:
Fitness level may influence baseline concussion symptom reporting with fitter
individuals reporting fewer concussion symptoms.  Athletes also appear to report more
concussion symptoms when reporting after exercise.

Baseline testing in concussion management, including graded
symptom assessment, has become commonplace in multiple sports on almost every
level of competition.  Different
assessment tools (e.g., Sideline Concussion Assessment Tool [SCAT3], Immediate
Post-Concussion Assessment and Cognitive Testing [ImPACT]) establish a baseline
for many nonspecific symptoms so that post-injury symptoms may be compared to baseline
results.   Previous research
has shown that multiple factors, including physical-activity level, can result
in reports of more neurological symptoms. Therefore, Mrazik, et al sought to
evaluate if an individual’s fitness level correlated with report of concussion
symptoms at baseline. They hypothesized that after exertion, athletes with
higher fitness levels would report fewer symptoms at baseline.  During scheduled preseason fitness
evaluations, 95 collegiate athletes and 30 recreational athletes completed the
SCAT2 symptom report before, 10 minutes after, and one day after the Leger 20-m shuttle-run test (a.k.a. beep test).  Based on the Leger shuttle run, the authors
estimated an athlete’s peak aerobic power, which they used to determine fitness
level. Athletes were then grouped for analysis based on participation in
contact versus non-contact sports and subdivided based on level of fitness (per
American College of Sports Medicine guidelines).  Results showed that athletes in better
physical condition had lower baseline SCAT2 symptom scores before, immediately
after, and 1 day after exertional activity. 
All athletes reported more symptoms immediately after exertional
activity when compared to pre-exertion reporting, but the number of symptoms
went back down after 24 hours.

The results of this study are noteworthy because they
highlight the importance of individual athlete variables that may potentially
influence subjective self-reporting.  The
timing of self-reporting also appears to be influenced by physical exertion
which is important to consider given that many athletes complete pre-season
concussion baseline testing with other pre-season testing that may involve
physical activity, such as strength and conditioning assessments.  While there are currently no guidelines to
suggest specifically when pre-season SCAT assessments should be conducted,
these results suggest that self-reporting assessments should not be conducted
in conjunction with exertional activity.  

Do you have any experience with athletes participating in baseline
testing after exertional activity? Do you think guidelines should exist as to when
pre-season baseline testing should be conducted?

Written by: Stephen Stache, MD
Reviewed by: Marc Harwood, MD and Jeffrey Driban

Related Posts:

Mrazik, M., Naidu, D., Lebrun, C., Game, A., & Matthews-White, J. (2013). Does an Individual’s Fitness Level Affect Baseline Concussion Symptoms? Journal of Athletic Training DOI: 10.4085/1062-6050-48.3.19