title: Exertion Testing in Youth with Mild Traumatic Brain Injury/Concussion.
abstract: OBJECTIVE
  The decision regarding return to activity (RTA) after mild traumatic brain injuries/concussion is one of the most difficult and controversial areas in concussion management, particularly for youth. This study investigated how youth with postconcussion syndrome (PCS) are affected by exertion and whether standardized exertion testing using the McMaster All-Out Progressive Continuous Cycling Test can contribute to clinical decision making for safe RTA.
  
  
  METHODS
  Fifty-four youth (8.5-18.3 yr) with a previously confirmed concussion participated in the study. Each participant performed exertion testing on a cycle ergometer and completed a Postconcussion Symptom scale at the following time points: before exertion (baseline), 5 and 30 min, and 24 h after exertion. A modified Postconcussion Symptom scale was administered at 2-min intervals during exertion.
  
  
  RESULTS
  Participants had a mean ± SD symptom duration of 6.3 ± 6.9 months after the most recent concussive injury, with a median of 4.1 months (range, 0.7-35 months). Sixty-three percent of participants had symptoms during exertion testing. Symptom profile (number and severity) significantly affected perception of exertion at 50% peak mechanical power. During acute assessment of symptoms (30-min after exertion), headache (P = 0.39), nausea (P = 0.63), and dizziness (P = 0.35) did not change. However, both the number and severity of symptoms significantly improved over 24 h, with 56.8% of youth showing improvements. The time from the most recent injury had a significant effect on the symptom score at baseline, 30 min after exertion, and 24 h after exertion.
  
  
  CONCLUSIONS
  Exertion testing has an important role in the evaluation of symptoms and readiness to RTA, particularly in youth who are slow to recover. Overall, controlled exertion seemed to lesson symptoms for most youth.
authors: 1CanChild Centre for Childhood Disability Research, McMaster University, Hamilton, Ontario, CANADA; 2School of Rehabilitation Science, McMaster University, Hamilton, Ontario, CANADA; and 3Child Health and Exercise Medicine Program, Department of Pediatrics, McMaster University, Hamilton, Ontario, CANADA.
authors: Carol
authors: C
authors: Dematteo
authors: Kimberly A
authors: KA
authors: Volterman
authors: Peter G
authors: PG
authors: Breithaupt
authors: Everett A
authors: EA
authors: Claridge
authors: John
authors: J
authors: Adamich
authors: Brian W
authors: BW
authors: Timmons
mesh_terms: D000293:Adolescent; D002648:Child; D003430:Cross-Sectional Studies; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006801:Humans; D008297:Male; D005082:Physical Exertion; D038223:Post-Concussion Syndrome / Q000503:physiopathology*; D000068958:Return to Sport; D013997:Time Factors