one4smoke

I have read through this thread because I experienced something similar last week. I rode 103 miles, which was my third century this year, and had most of the hard climbing after about mile 70. I hadn't felt as energetic as I do on most rides, but not just terrible either. About halfway into the last 30 miles, I found myself with several big hills left to go to get back to my SUV. One, about a 15° gradient that really had me concerned that I may not make it, because I was feeling absolutely spent. I had about the same symptoms you described. Probably not nutritionally correct, but I stopped at a Target that was just off the path to get a Coke and Snickers bar. I made it up the big hill with about 8 miles to go, but just barely. Took all I had. With about 5 miles left, that hill behind me and flat ground ahead, I starting feeling much better. Maybe psychological, maybe the Coke and candy bar ...I don't know.

There's a lot of advice here, some probably good, and some probably over the top as mentioned. But in my humble (and not the best, most experienced cyclist to give advice) opinion ...I think it just comes down to the fact that some days you have IT, and some days you don't. No matter how much rest or sleep you get the night before, or what or how much you eat. I've had some of my best, most energetic rides with very little sleep and little or no food. Then some of my worst with great sleep and "ideal" nutrition. And of course, the outcome has been just the opposite of those scenarios also. It's my experience there's no rhyme or reason to being able to predict how well you will feel on a ride.

I mentioned about feeling better 5 miles from the end of my ride maybe being psychological. I honestly think that could apply to an entire ride as well. Sometimes it's simply the attitude you have about it, and not so much all the other stuff.