I used to have terrible problems with DOMS after races. I'd be a cripple for a couple days after a marathon. But since going barefoot and minimal, that really does seem to be a thing of the past. The
why I'm not sure about but intuitively, it feels to me like I now engage all the muscle groups that are supposed to be part of running, whereas running in shoes with a built-up heel takes the Achilles out of the fomula, overburdening some muscle groups while allowing others to become sort of dormant. When the whole system is functioning as intended, it also deals with the stresses of competition better. Sounds good to me but is basically a way of saying, I dunno, feels good, do it
But it's gotta also be a simple matter of training and experience. If you train a lot at race paces, then the body will adapt to those paces, over time. If you don't, then you're going to feel something after a race.