Exercise as Treatment for Postconcussive Symptoms

Some scientists have theorized that concussive symptoms are produced by physiologic autonomic dysfunction, characterized by altered autonomic function and impaired distribution of cerebral blood flow, which can persist for several weeks. This research group, which previously studied the exercise stress test as a diagnostic tool for concussion, has proposed treating concussive symptoms by gradually increasing aerobic exercise. Now, they have examined changes in brain activations in eight consecutive concussion patients before and after 12 weeks of aerobic exercise (20 minutes/day at 80% maximum heart rate; 6 days/week) or stretching.

Patients and four healthy controls underwent functional magnetic resonance imaging while completing a math task. Patients (age range, 17–52; 50% women; duration of symptoms, ≥6 weeks and ≤12 months) had an identifiable heart rate threshold for exacerbation of symptoms. The first patient group was assigned to exercise, the second to stretching. The exercise program was modified as patients achieved higher heart rates before their symptoms worsened.

At baseline, the two concussion groups had similar imaging findings; the healthy control group had greater activation in posterior cingulate, lingual gyrus, and cerebellum. After 12 weeks, the exercise group now had imaging findings similar to the control group's, had significantly decreased symptoms, and exercised at a higher heart rate. Patients who stretched had lower activity in thalamus and left anterior cingulate than controls.