Hi Matt and welcome to the EF!
I'm not sure if they have one in Zürich but here in Basel there is a running club... perhaps some of the Zürich folks can point you in the right direction if there is one. (I'm not a runner but I know that if I did get in the mood, making it a social "event" would help keep me motivated).
Speaking of clubs and such, do take a peek down at the Activities section, particularly Social Events - usually there is something going on in or around Zürich. Who knows, you and your gals may find something new and fun to do.