I know in rugby there are very strict protocols to follow after a concussion. I think its a minimum 2 week rest period (no exercise at all), then a "graduated return to play" which can take another 2 weeks or more. For professionals these periods can be reduced if they are regularly monitored by a qualified doctor, but even for a less physical sport such as football (which is still a contact sport) I cant see anyone being back in less than 2-3 weeks.
FWIW, these are the FA return to play guidelines:
Concussion is a brain injury. There is no blood test or scan currently available that can diagnose it. The diagnosis is made on the basis of history and examination. Return to play after head injury/concussion should be treated as with any other injury. A period of rest, which, in this case, includes mental activity, should be followed by a gradual return to play, closely monitored by medical staff. Serial evaluations using SCAT 3, or whichever pre-season assessment was employed, should be used as an objective adjunct of measure of recovery.
The player should undergo a period of physical and mental rest for at least 24 hours after the injury (which includes the playing of video games or similar).
The physical return to play ‘steps’ should follow the course shown below, only progressing to the next step if there are no persistent/recurrent concussion symptoms, such as such as headache, feeling in a fog, disturbed or blurred vision, sleep disturbance, or unusual emotional behaviour
This process should also include serial SCAT 3 assessments, or assessment with whichever pre-season neuro-psychological assessment tool was employed.
The chosen neuro-psychological testing should be carried out every 48 hours after the injury, until return to play, and should show a gradual return to baseline. Clinical assessment should be made daily, whilst following the rehabilitation programme as outlined below.
Any recurrence or persistence of concussion symptoms such as headache, feeling in a fog, disturbed or blurred vision, sleep disturbance, or unusual emotional behaviour are signs that the player should return to the previous ‘return to play step’.
An improvement in the serial assessments, both clinical and neuro-psychological, whilst increasing the players’ work load, is an indication that they are ready to progress to the next step.
The physical activity ‘steps’ of rehabilitation should follow this protocol.
a) No activity
b) Light aerobic exercise
c) Sports specific exercise
d) Non-contact training drills
e) Full contact practice
f) Return to play
Each of these steps takes at least one day
The player should not be allowed to return to play for at least 6 days after the injury (it often takes longer than this) and in strict accordance with the return to play guidelines (above). This will include a return to baseline of the SCAT 3, or web-based, neuro-psychological criteria. A baseline profile will be available from the pre-season assessment.
The player should be examined, and receive the ‘all clear’ from the club medical officer before returning to play.
If progression back to full fitness is delayed in any way, urgent specialist advice should be sought for further assessment.
Any player who has suffered two or more concussive episodes during a season should be discussed with a suitably qualified neurological specialist prior to return to play.
