Yup. Ramp tests, races, hard group drop rides. Any time where I’m fresh and highly motivated I have the potential to dig myself into a hole unfortunately! Several hours (or the rest of the day…) of being barely functional, several days of rest or easy training to recover, if it’s a long ride or race it can often be the trigger for getting sick as well. Not a fuelling issue, and it’s something that’s happened to me throughout 25+ years of training for various sports.
My only solution is to try not to go that deep unless it’s a race (can’t race at anything less than 100%!). Doing it in training/testing is counterproductive. Not only does it wipe out a few days of training, if it’s in a test it can also give me an FTP number that I end up having to adjust down anyway to get through the block. Being fresh does seem to be a big factor though, as it’s typically after a recovery week or taper that I find the ability to squeeze out that few extra % that does the real damage. When I’m in the middle of a training block and carrying some fatigue I don’t really have to hold back at all.
I think there’s a plus side to it though. Over the years I’ve found that on those days when I am tapered and prepared to go as deep as I can regardless of the recovery cost, then I tend to get a bigger performance boost relative to my training fitness than most of the people I train with. Often put in race day performances that surprise both myself and others that know me. Just unfortunate that they also often are followed by at least several days and sometimes several weeks of trying to get back to normal 