Speed up turn by turn prompts

Before I went running at the weekend on a new route, I setup a course and sync'd it with my 5+. When out running the watch was prompting me to turn ahead of the actual turn, like it normally does ~50m from the junction, but when I actually got to the junction it was not prompting me until after I passed it.

Is there anyway I can change this? I think it's just a little bit slow to react (or I run too fast :))

Thanks