Was curious about this topic as twice now i've been much more tired than usual the day after a bigger effort ride. Any decent effort ride reminds me the next day of what i was doing the day before, but usually stiffer legs, lower back etc and all that eases up during the course of the day. In this case it was slightly different in that the following day i felt very tired (could of just gone to sleep) in the afternoon and just zonked out later that evening which is something i never do. Wondered if i was coming down with something but otherwise i feel absolutely fine so ruled that out and it did remind me that i was pretty much the same on a previous occasion which was also the day after a bigger effort ride. I know it's hard to judge without knowing fitness, energy and effort levels but was interested to see if this is something common ?
Or is it all just an excuse as i'm getting older