I'm usually the oldest soloist at 24 hour races, almost certainly the oldest on a single speed. (Brain deterioration – can't work out gears)
I have qualified for this years World Solo 24 hour Championship in Oz so I may have to learn how to use gears to have a chance 🙂
Generally speaking I don't suffer much from aches and pains, even after long rides, except when I have been off the bike for a period, eg travel, injury. I think it's important to ride conservatively when you age because injuries keep you off the bike much longer (or is that an excuse for me being a woose?)
So to anyone under retirement age, age is no excuse – get on yer bike and stop moaning 😆