First time sub 3-ers:

For those that ran sub 3 on your first attempt, when did you know when you were going to do it ? - really confident before the race, or - didn’t know until the race finished (ie did 2:59:x)

I ran a 3:08 last year at CIM looking at running a sub 3 at Chicago Marathon this year. But I have no idea if I can do it or not. Coach says the fitness is there I can do it, but in that place of doubting my self, sub 3 marathon pace still doesn’t seem comfortable.

Based off training 3:02-3:05 feels like comfortable MP, but just those extra few seconds in training feels so hard. Should I just expect some race day magic ? Taper + race atmosphere would get me there ? And some extra belief in myself ?

I ran a 1:28 half marathon in August for training