Can rolling off a pelatius ball during a gym workout cause serious damage especially if the person hit the back of his head against a iron clad wall edge - person got hit at the medulla oblongata area. Did not show any visible signs for over 5 days before succumbing to an attack resembling a brain stroke. The person experienced a sense of paralysis in his left hand and leg during the workout at the gym? He managed to walk 20 minutes away from Gym and went to sit down at local juice bar before passing out.