You need to redirect them. Give warning all the time eventually they understand.
Unfortunately my son is the exact opposite! He is a right chicken (obviously I don’t say this to him) he is often too scared to go down slides at soft play, or go on roundabouts, or anything id love to be able to do with him. I really don’t know where it’s come from. We try to gently encourage him to do things but obviously don’t force him if he says he doesn’t want to, or is scared. Any tips on how to help him be a little more adventurous greatly received 😂
I don't have any advice I'm afraid, but my little boy is exactly the same!