I was working out at home and part of my workout consisted of doing pull-ups to failure and repeating. On my last set, I was really straining to finish "just one more". I cranked out the last rep and dropped to the ground...BAM! I felt what literally felt like an explosion in my head. Whoa...I don't feel so good.
So...being a "guy" (read lacking completely in common sense) I waited two minutes until my next round of exercises. Dips I believe. One set of 12 dips, now I really don't feel so good. I turn to my wife (a neurological nurse) tell her what just happened during the pullups...I get "the look" (ie. what kind of an idiot are you, why didn't you stop)...I tell her that "I'm not feeling good", lie down on the floor and the world starts going really dark and blurry around the edges, my hearing becomes really muffled, my tongue starts "buzzing" and a hint of nausea starts. I vaguely see Theresa standing over me about 100 feet away at the end of a tunnel asking if she should call an ambulance as I have no color and my eyes are not focussing. I nod assent and a few minutes later some nice guys from the fire department show up with o2.
A couple minutes later the Ambulance shows up. By this time I have turned a really nice shade of grey but the world has returned to normal for me. They ask if I want to go to the hospital, I say no but as I understand it since I couldn't walk in a straight line they took me anyhow. I laugh at it now but when they were taking my vital signs, I understand that they showed-up as "normal" and Theresa is telling them "NO, you don't understand...he's in great shape and those readings are off the chart for him...this in NOT normal." Gotta love those nurse advocates!
Long story short...several ct scans and and MRI, consult with a neurologist...nada. We have absolutely no idea what you did to yourself. There is no sign of stroke or bleeding or damage or any lasting sort.
Here was their best guess. You were holding your breath too much while doing pullups and you built up such a great deal of pressure in your head that when you dropped off at the end, it was like a "pipe bang" as the blood stalled and started again. This was the "bang" you felt. You then had a vasovagal response from the event and passed out from it.
So...I don't know if any of this sounds at all similar but I offer my own stupidity for the record. I would also recommend totally that hydration and eating are not to be avoided prior to working out. You could avoid eating if you are working out first thing in the morning on an empty stomach for fat burning but I would still hydrate. Going all day and working out seems to be counter to every study ever written on muscle building. You need the food to build the muscle. Otherwise, your body thinks it's starving and will flip into fat storage mode as soon as you have your next meal.
Good luck to ya!
Brian