never a big drinker, did one speed workout after a night out and that was the end of that.
however, i would have 3 pints the day before a race, it would take the edge off the going to war mental state, which ruined sleep.
this over hype before a race, that is fear, which is normal prep, but out of control it burns you out.
some guys are fine with it, until they come to something like an olympic games, when emotions go to a new level, and they can't rest, a new experience, and it ruins some.
some guys get quite nervous but sleep in the afternoon before the big one.
myself, i would tend to do well once the bigger thing was on, as it was kind of relaxing to finally be where you wanted, with the caveat. that it was small time stuff.
it's all mental. and something you can do through meditation, psychology, natural sedatives like magnesium at the right time, deep breathing.
back in the day, your coach helped, but you were on your own.