My house mate who rides BMX has died twice from riding, had to be resuscitated and was in a coma for 3 months. He woke up from his coma with no idea where he was, who he was, how he got there or how to do everyday things like read and write. He has had to learn it all again, he forgot that he rode until i showed him his bike and he swung a leg over, one of the few things he remembered how to do.