[shmat]

I cycle 4 days a week for 2 - 4 hours each ride. I have tried various kinds of fasting including 16:8 and 5:2 and they've all been a disaster. I have extensive split times for the same rides and after accounting for wind/temperature, when fasted, I slow down about 3% after 90 minutes. After 2 hours, I slow down 5%. After 3 hours, I slow down 15% and feel terrible. I also feel more tired for the rest of the day. Even if I don't fast on ride days and fast on the other 3 my ride times are slower and my recovery is harder. I've kept up the fasting for at least 3 months to see if my body will adjust, but it does not work for me. Now, I practice 16:8 in the winter when I'm riding less but not during the main season.