To determine whether graded exercise testing can predict recovery trajectory of concussion in children and adolescents.
Children's Hospital, Westmead, Australia.
One hundred thirty-nine children aged 12 to 16 years at 5 to 7 days after an acute concussive injury.
Graded exercise testing on a treadmill at the subacute phase to assess symptom provocation and determine clinical recovery indicating readiness to commence a return to activity (RTA) protocol. Exercise time to symptom exacerbation and clinical recovery were measured.
Standard concussion assessment and clinical testing (neurocognitive, vestibular/ocular, and balance) were conducted to determine major clinical drivers/indicators.
Participants (mean age 12.4 ± 2.8 years, 73% male) had a confirmed sport-related concussion. The main clinical drivers identified on exercise testing were headache, balance, and vestibular dysfunction. Participants fell into 1 of 2 groups, exercise-tolerant (54%) and exercise-intolerant (46%). Exercise-tolerant patients showed mild clinical indicators, no symptom exacerbation during 10.3 ± 3.3 minutes of exercise, were safely transitioned to a RTA protocol, and recovered within 10 days. Exercise-intolerant patients had high clinical indicators, significant symptom exacerbation at 4.2 ± 1.6 minutes of exercise, and prolonged recovery of 45.6 days. No adverse effects from exercise were reported in either group. Combined use of provocative exercise and clinical testing was 93% predictive of outcome.
Exercise testing during the subacute phase after a concussion can predict longer recovery. Exercise testing can identify a unique window where patients can be safely transitioned to activity, enabling clinicians to better inform patients and families, allocate resources and streamline care.
*Discipline of Exercise and Sport Science, Faculty of Health Sciences, and Discipline of Emergency Medicine, The Children's Hospital at Westmead Clinical School, The University of Sydney, Sydney, Australia;
†Sydney Children's Hospital Network, Children's Hospital Institute of Sports Medicine, The Royal Alexandra Hospital for Children, Children's Hospital Westmead, Sydney, Australia;
‡Graduate School of Health, Faculty of Health, University of Technology Sydney, Sydney, Australia; and
§Discipline of Child and Adolescent Health, Sydney Medical School, The University of Sydney, Sydney, Australia.
Corresponding Author: Rhonda Orr, PhD, Discipline of Exercise and Sport Science, Faculty of Health Sciences, and Discipline of Emergency Medicine, The Children's Hospital at Westmead Clinical School, The University of Sydney, 75 East Street Lidcombe, NSW, 2141 (firstname.lastname@example.org).
The authors report no conflicts of interest.
G. J. Browne devised the study concept and design. G. J. Browne and T. Bogg conducted the study, and performed the collection and interpretation of data. L. T. Lam conducted statistical analyses. G. J. Browne, T. Bogg, and L. T. Lam drafted the manuscript. A. Fyffe conducted further analysis and interpretation of data. R. Orr interpreted data, critically revised the manuscript, and contributed further intellectual content. All authors approved the final manuscript.
Received February 20, 2018
Accepted June 23, 2018