Actually I think that's what triggers it. LOL
Happened back when I was road riding and started up again when I started at the gym, which includes a good bit of stationary bike. I go every other day and it seems those nights are the worst.
A hot shower helps relax it, but hopping up to take a 2nd shower at 1am kind of sucks.
My diet is probably the best it's ever been in my life, so I shouldn't need the supplements, but I tried anyway.

I wonder if cutting waaay back on caffeine might have something to do with it? I don't get headaches though.