Aerobic therapy (AT) may lessen the symptoms experienced by children and adolescents suffering from post-concussion syndrome and allow them to return to baseline, report researchers in a paper presented at the American Academy of Pediatrics National Conference and Exhibition in October 2015 in Washington, D.C. 
Researchers, led by William R. Johnson of the Perelman School of Medicine at the University of Pennsylvania, reviewed the charts of 57 pediatric patients with post-concussion syndrome presenting to a specialty sports medicine concussion program at a large children's hospital from 2011-2013 who were referred to physical therapy (PT) for post-concussion symptoms.
Extracting data from each PT visit with AT, along with the number of symptoms, symptom severity, exercise time, completed exercise, and symptoms with exercise, they found that the percentage of patients who reported concussion symptoms dropped from 93% at their first PT visit to 42% at discharge from physical therapy.
Two-thirds of the patients were able to complete AT during their initial PT session, with exercise inducing post-concusive symptoms in slightly more than half (54%). At their final PT session, nine out of ten were able to complete the exercise, with exercise inducing post-concussion symptoms in only 9%.
While conceding that further study was needed to prospectively compare outcomes in post-concussion syndrome patients treated with and without AT, the authors concluded that exersise appeared to be both tolerated by pediatric patients with post-concussion syndrome and to result in a reduction of symptoms.
When an athlete is unable to transition back into an active lifestyle, they are at risk for secondary problems such as physical deconditioning, anxiety and stress, mild depression, and irrritability. Over time, the strength of the relation between the original injury and ongoing symptoms very likely diminishes, and the pre-existing, current and contextual factors increasingly contribute to causing, maintaining, or exacerbating symptoms. 
The accepted wisdom that PCS should be treated with rest, reassurance and anti-depressants, and that physical activity should be avoided, however, is now being questioned, with the authors of a 2013 systematic review of the literature on the effects of rest and treatment following sport-related concussion  noting that "[c]onverging lines of diverse, albeit indirect, medical and scientific evidence [now] support the use of exercise as a core component of treatment for children, adolescents, and young adults who are slow to recover from concussion."
In a landmark 2010 study published in the Clinical Journal of Sports Medicine,  researchers at the State University of New York at Buffalo (SUNY-Buffalo) reported that a program of progressive exercise developed individually for each participant and performed at levels just below the onset of symptoms was safe and relieved nearly all PCS symptoms.
The SUNY-Buffalo regimen is based on the hypothesis that the regulatory system responsible for maintaining cerebral blood flow, which may be dysfunctional in people with concussion,  can be restored to normal by controlled, graded, symptom-free exercise. A 2013 pilot study by the same researchers provided preliminary evidence to support that hypothesis. 
"Perhaps the most exciting aspect of this study is that all of the subjects that participated, both athletes and non-athletes, got better eventually, although the athletes certainly improved the fastest," said Barry Willer, PhD, UB professor of psychiatry and rehabilitation sciences and senior author on the study, in a January 2010 SUNY-Buffalo press release. 
"It also was reassuring to discover that the use of exercise was safe and did not prolong symptoms, a worry expressed by other practitioners."
Physicians in UB's Sports Medicine Concussion Clinic initially used their approach only with athletes from UB teams, but word spread, and they now have assessed and treated many professional athletes, especially those from the National Hockey League.
"One of the advantages we offer to professional teams is a more precise test of post-concussion syndrome," says John J. Leddy, MD, associate professor of orthopaedics and co-director of UB's Sports Medicine Institute. "If the patient does not develop symptoms during the exercise test, then the cause of their difficulties is likely to be another source. Most commonly it is neck strain, which tends to cause headaches that mimic post-concussion headache."
"The data suggest that some PCS symptoms are related to disturbed cerebral autoregulation, and that after this treatment, the brain was able to regulate blood flow when the blood pressure rose during exercise," says Leddy. "We think progressive stepwise aerobic training may improve cerebral autoregulation by conditioning the brain to gradually adapt to repetitive mild elevations of systolic blood pressure."
"Although each concussion should be considered a 'unique injury,' a randomized trial that included a PCS control group should be conducted to address the possibility that PCS symptoms would have resolved spontaneously without intervention, said study co-author Karl Kozlowski, PhD, UB clinical instructor of exercise and nutrition sciences, who developed the exercise protocol.
"All of our subjects had been symptomatic for months before treatment and were not getting better on their own," says Kozlowski, "so we are pretty convinced that the regulated exercise program did the trick."
1. Research paper, Exercise Tolerance in Pediatric Patients with Post-Concussion Syndrome. Johnson WR, et. al. Presented at American Academy of Pediatrics National Conference and Exhibition, October 24, 2015. Washington, D.C.
2. Leddy J, et. al. A Preliminary Study of Subsymptom Threshold Exercise Training for Refractory Post-Concussion Syndrome. Clin J Sport Med 2010; 20(1):21-27 (doi: 10.1097/JSM.0b013e3181c6c22c).
3. Neary J. et. al. Cerebrovascular Reactivity Impairment after Sport-Induced Concussion, Med & Sci in Sports & Exercise 2011;43(12): 2241-2248.
4. SUNY-Buffalo, UB Specialized Exercise Regimen Shown to Relieve Prolonged Concussion Symptoms. http://www.buffalo.edu/news/10848 (accessed December 10, 2011).
5. Schneider K, Iverson G, Emery C, McCrory P, Herring S, Meeuwisse W. The effects of rest and treatment following sport-related concussion: a systematic review of the literature. Br J Sports Med. 2013;47:304-307.
6. Leddy J, Sandhu H, Sodi V, Baker J, Willer B. Rehabilitation of Concussion and Post-concussion Syndrome. Sports Health: A Multidisciplinary Approach 2013;4(2):147-154,
7. Leddy JJ, Cox JL, Baker JG, Wack DS, Pendergast DR, Zivadinov R, Willer B. Exercise Treatment for Postconcussion Syndrome: A Pilot Study of Changes in Functional Magnetic Resonance Imaging Activation, Physiology and Symptoms. J Head Trauma Rehabil 2013;28(4):241-249.
Posted November 24, 2015