A preliminary study of subsymptom threshold exercise training for refractory post-concussion syndrome.
OBJECTIVE
To evaluate the safety and effectiveness of subsymptom threshold exercise training for the treatment of post-concussion syndrome (PCS).


METHODS
Prospective case series.


METHODS
University Sports Medicine Concussion Clinic.


METHODS
Twelve refractory patients with PCS (6 athletes and 6 nonathletes).


METHODS
Treadmill test to symptom exacerbation threshold (ST) before and after 2 to 3 weeks of baseline. Subjects then exercised 5 to 6 days per week at 80% ST heart rate (HR) until voluntary peak exertion without symptom exacerbation. Treadmill testing was repeated every 3 weeks.


METHODS
Adverse reactions to exercise, PCS symptoms, HR, systolic blood pressure (SBP), achievement of maximal exertion, and return to work/sport.


RESULTS
Pretreatment, ST occurred at low exercise HR (147 + or - 27 bpm) and SBP (142 + or - 6 mm Hg). After treatment, subjects exercised longer (9.75 + or - 6.38 minutes to 18.67 + or - 2.53 minutes, P = .001) and achieved peak HR (179 + or - 17 bpm) and SBP (156 + or - 13 mm Hg), both P < .001 versus pretreatment, without symptom exacerbation. Time series analysis showed significant change in rate of symptom reduction for all subjects and reduced mean symptom number in 8/11. Rate of PCS symptom improvement was related to peak exercise HR (r = -0.55, P = .04). Athletes recovered faster than nonathletes (25 + or - 8.7 vs 74.8 + or - 27.2 days, P = .01). No adverse events were reported. Athletes returned to sport and nonathletes to work.


CONCLUSIONS
Treatment with controlled exercise is a safe program that appears to improve PCS symptoms when compared with a no-treatment baseline. A randomized controlled study is warranted.
Leddy
John J
JJ
Department of Orthopaedics, University at Buffalo, The State University of New York, Buffalo, NY 14214, USA. leddy@buffalo.edu
Kozlowski
Karl
K
Donnelly
James P
JP
Pendergast
David R
DR
Epstein
Leonard H
LH
Willer
Barry
B
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001265:Athletic Injuries / Q000150:complications / Q000534:rehabilitation / Q000628:therapy*; D005080:Exercise Test; D005081:Exercise Therapy; D017079:Exercise Tolerance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D038223:Post-Concussion Syndrome / Q000150:complications / Q000534:rehabilitation / Q000628:therapy*; D011446:Prospective Studies; D013223:Statistics as Topic; D013997:Time Factors; D055815:Young Adult