I raced bicycles in college and I can say with confidence that after a 4-6 hour training ride I was wiped out physically and mentally. Had an explosion gone off when I was in that state and only a few blocks from home I would have made sure I was OK and kept pedaling for gatorade and a shower. I don't see their behavior as terribly puzzling given my fairly extensive experience with an exhausted state of mind.
I had done serious mountain biking and my worst injuries are not from doing extremely dangerous things like hard dropping from a 3 meter slippery stone, witch is something you prepare very well, but for really really stupid errors when being physically, and specially mentally exhausted.
I was 2centimeters away from losing an eye, with itching and hurting wounds in my face, some fractured bones.
On retrospect it was like part of my brain disconnected for most of the time when exhausted.
I could understand the man whose legs stop supporting him with the blast, hopefully he recovers.
