What is Second Impact Syndrome?
Second Impact Syndrome (SIS) occurs when an athlete who sustains a head injury subsequently
receives a second head injury before full resolution of the first symptoms. Re-injury need not
occur on the same day and has been reported up to four days following the first concussion with
brief loss of consciousness (Erlanger, 1999).
At the time of the second concussion, the impact might appear minor and the athlete may just
Who does SIS Effect?
Some of the research that has been completed on SIS, indicates that athletes under the age
Real Life Stories of SIS