Quote Originally Posted by ponte_ricky View Post
I've come across the Naismiths rule before briefly but isnt that more applicable to hiking?
Naismith's works just as well for fellrunning too, though I've found from personal experience that the ratio is more like 1:8 (100m climb = 800m distance) since we're used to doing hills.

And bear in mind the extension to Naismiths about steep descents being slower too. That's even more dependent on terrain, but 1:2.5 (100m steep descent = add 250m distance) is a very rough approx.

Anyway... that's my take on Naismiths since you mentioned it.