To evaluate (1) systematic assessment of exercise tolerance in adolescents shortly after sport-related concussion (SRC) and (2) the prognostic utility of such assessment.
Prospective randomized controlled trial.
University and community sports medicine centers.
Adolescents with SRC (1–9 days from injury). Sixty-five were randomized and 54 completed the study (mean age 15 years, 4 days after injury).
Buffalo Concussion Treadmill Test (BCTT, n = 27) or not (controls, n = 27) on visit day #1. Heart rate threshold (HRt) at symptom exacerbation represented level of exercise tolerance. Participants reported symptoms daily for 14 days and then had follow-up BCTT (n = 54). Recovery was defined as returning to normal level of symptoms and exercise tolerance, verified by independent physician examination.
Days to recovery and typical (≤21 days) versus prolonged recovery (>21 days). Mixed effects linear models and linear regression techniques examined symptom reports and time to recovery. Linear regression assessed the association of HRt with recovery time.
Days to recovery (P = 0.7060) and typical versus prolonged recovery (P = 0.1195) were not significantly different between groups. Symptom severity scores decreased in both groups over 14 days (P < 0.0001), were similar (P = 0.2984), and did not significantly increase the day after the BCTT (P = 0.1960). Lower HRt on visit day #1 was strongly associated with prolonged recovery time (P = 0.0032).
Systematic evaluation of exercise tolerance using the BCTT within 1 week after SRC did not affect recovery. The degree of early exercise intolerance after SRC was important for prognosis. This has implications for school academic and team preparation.
From the *UBMD Orthopaedics and Sports Medicine, SUNY Buffalo, Buffalo, New York;
†Department of Biostatistics, SUNY Buffalo, Buffalo, New York;
‡Excelsior Orthopedics and the Department of Family Medicine, SUNY Buffalo, Buffalo, New York;
§Nuclear Medicine, SUNY Buffalo, Buffalo, New York;
¶Department of Internal Medicine, SUNY Buffalo, Buffalo, New York; and
‖Department of Psychiatry, SUNY Buffalo Jacobs School of Medicine and Biomedical Sciences, Buffalo, New York.
Corresponding Author: John J. Leddy, MD, FACSM, FACP, UBMD Orthopaedics and Sports Medicine, 160 Farber Hall, Buffalo, NY 14214 (leddy@buffalo.edu).
Research reported in this publication was supported by the National Institute of Neurological Disorders and Stroke of the National Institutes of Health under award number 1R01NS094444.
The authors report no conflicts of interest.
The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Received June 09, 2016
Accepted January 05, 2017
