I just completed my second double century. Both times, my eyes were bloodshot and stayed red for a couple days. I wore Oakley prescription sunglasses the entire ride the first time, switched to regular prescription glasses for the last 2 hours the second time (in the dark). I also tried to remember to blink frequently, yet it doesn't seem to have helped. I don't have this problem for century distances. Any ideas what could be causing it, and how to reduce it? I thought of using contact lenses with a different pair of glasses, but this could be potentially even worse.