Randomized controlled trial of early aerobic exercise following sport-related concussion: Progressive percentage of age-predicted maximal heart rate versus usual care.

OBJECTIVE: To examine the effect of a readily accessible, structured aerobic exercise intervention on days to asymptomatic status and days to medical clearance compared to usual care exercise prescription in a cohort of adolescents and young adults following sport-related concussion (SRC). METHODS: A longitudinal, randomized, non-blinded clinical trial consisting of a structured aerobic exercise protocol (SAEP) group and a usual care exercise prescription (UCEP) group. Participants in the SAEP group underwent an exercise protocol including 8 sessions over 11 days progressing in duration and intensity stepwise based on participants' age-predicted maximal heart rate. Symptom follow-ups were on days 7, 14, 21, and 28. The primary outcome measures of the study were days to asymptomatic status and days to medical clearance, while the secondary outcome measure was symptom severity on days 7, 14, 21, and 28. RESULTS: 38 participants (SAEP, n = 20; UCEP, n = 19) were recruited and completed all follow-up appointments. Compared to the UCEP group, the SAEP had a faster time to asymptomatic status with 96% posterior probability. In addition, the SAEP group displayed an earlier time to medical clearance with 93% posterior probability. While symptom severity scores did not differ between groups at enrolment (SAEP symptom severity, 30; UCEP, 29), they were subsequently lower in the SAEP group at all assessments throughout the trial with 100% posterior probability. CONCLUSIONS: An aerobic exercise protocol based on percentages of age-predicted maximum heart rate is a safe and effective treatment for reducing symptoms and can be initiated during the first week following SRC. TRIAL REGISTRATION: ClinicalTrials.gov, no. NCT02969824.

Ten-Word List Performance in Healthy Athletes and Athletes at 3-to-5 Days Following Concussion.

OBJECTIVE: Although the word recall component of the Sport Concussion Assessment Tool (SCAT) was updated from 5-to-10 words, its clinical utility across athletic populations remains unknown. The purpose of this study was to provide normative data on the SCAT-5 10-word test and examine its discriminative ability between healthy university level athletes and those with sport-related concussion (SRC). DESIGN: Cross-sectional. SETTING: University. PARTICIPANTS: Three hundred sixty-three (363, M = 220, F = 153) healthy athletes and 49 (M = 30, F = 19) athletes following SRC. INDEPENDENT VARIABLE: Healthy athletes measured preseason were compared with athletes following an SRC (median = 4.0 days postinjury). MAIN OUTCOME MEASURE: Ten-word list performance from the SCAT-5. RESULTS: There were no significant differences in either immediate ( P = 0.228, Cohen's D = 0.18) or delayed ( P = 0.908, Cohen's D = 0.02) recall tests between athletes with SRC and healthy athletes; the null findings extended to both the male and female subset comparisons. Among healthy athletes, females outperformed males on both immediate (mean difference = 1.0, P < 0.001) and delayed (mean difference = 0.5, P = 0.006) recall tasks. CONCLUSION: Concussion does not seem to impact immediate or delayed recall of the 10-word list in the subacute period following injury. Practitioners should be mindful of sex differences and the time point of administration following injury.