I ride 4-5 times a week mostly 1 -1.5 hrs on a trainer or road when I have time. Sat. rides is with a group ~50 miles with some hammering. I do my share of the pull specially on flats. My problem is post ride headache. I get a headache after a couple of hours after my Sat. ride. I made a point to eat within 2 hrs. after the ride and drink fluid constantly (Endurox immediately, sip Gatorade and water). But I still get that nasty headache. If I want to get rid of my headache, I take Excedrin; 30 min. and I'm good again. So what gives? By the way, I also consciously hydrate and eat during the ride. Thanks for any inputs you may have.