you're just so fit that you can't contol the speed :)
Cheers Helen...the problem is I haven't ever done 10km measured so have no idea what I'm capable of - this is a training plan worked out from my last run which I measured vaguely at 12km and wasn't really running properly hard on, and then worked out a 10km pace eg. total bollocks. I'm doing the Edinburgh 10km next weekend though, so then I'll have a proper time and a better training plan sorted!