As was wisely pointed out to me in another thread, part of my problem seems to be that my glycogen usage is likely soaring during the final third or so of 50-mile rides. I am looking for specific ideas on what kinds of "healthy" foods (in my medical situation, that might be, e.g., whole grains and fruits) that I can consume before I do a hard 50-mile ride, and, more important, similar healthy, portable foods I can carry and eat very frequently during those rides.
I just want to "wisely point out" that your glycogen usage is dependent on your status through out the ride. If anything is "soaring" on the final third of your ride it is because your effort and intensity have increased respectively.
I hope you elicit some healthy snack suggestions - good luck.