I've been on some cold runs lately, have been trying to work out how many layers are sufficient without getting too cold or too hot. There has been a lot of trial and error, came back one day from a 10 mile run and it took me 15 minutes to defrost my arms and hands. Good 11 mile run today, had three layers on top with two pairs of gloves, didn't get too cold this time but oh was it lovely to get in the bath when I got back!