I read a lot of sport medicine/ sport nutrition stuff in my free time. Somewhere along the line I read an article about bonking. Basically all of your energy stores are gone and your body starts breaking down whatever it can to keep you going. During this indiscriminate grab for energy the body can burn fat, muscle, and even brain cells for energy, at least according to the article.
 
So this past week I was at the gym for a run and swim. I changed, locked my crap up, and hit the treadmill. I pushed myself pretty hard on the 4 mile run and felt pretty wasted after it was over. I did a little walking to get my heart rate down from the 200bpm it was cranking out at the end of the run. After the cool down and a stretch I headed back to my locker so I could change for the swim. I found my locker (I use a green master lock so it sticks out) and turned in the numbers R2 L8 R22... nothing. Oh was it R8 L2 R22? Nope! Maybe it’s L2 R8 L22... no that doesn't work either. I try a few more numbers and even tossed in a 5 for good measure with no luck. So I standing in front of this locker thinking to myself I ran so hard that my body ate some brain cells and just happened to grab the ones that were keeping my lock combination. I've been using this lock for 2 years and never ran into this problem.
 
I decide I'm going to have security get the bolt cutters because I need my stuff (car keys, wallet ect.). And right before I turn to leave I glanced over and saw another green lock (two lockers down). I tried the original combo on this lock and it popped right open, all my crap was safe inside.
 
The moral of this story is keep working out hard and don't worry about killing a few brain cells. Maybe you should worry, after all I spent a good 5 minutes trying to open someone elses locker.