How long will you have to keep from running when you have a concussion?

Post concussion : Exercise should be limited post concussion. We use something call an impact test or a scat 2 test to tract symptoms. Scat 2 is on internet and down loadable. Must be symptom free for 72 hours. Then can attempt limited exercise for about 5-10 minutes. If no recurrent symptoms in 24 hours may return to full activities. If symptoms return, clock starts again, 72 hours symptom free, exertion test.