This. I live equal distance from 4 parkruns and each of them have narrow sections where it’s single file in places. At each one some of the faster runners can be overheard moaning and grumbling when they are held up. It’s rude and disheartening for the slower runners.I don’t mind people wanting to get a PB at parkrun but what I find very anti-parkrun spirit is on lapped courses where the faster people are rude and almost push people out of the way as they lap them. If you really want to race, sign up for a race. If you want to PB at parkrun, go for it but not at the cost of others (my friend was literally pushed over by one wanting everyone to get out of his way).