I cant tell you this will lead to a date but simply saying hello is a big ice breaker. Ita the follow up that gets tricky, any time you can find common interest, like working out, it gives u a follow up topic to chat about. From there I dunno, one thing I can tell you is if shes interested you will know pretty quickly by how zhe responds, if she chats you up then she maybe into you, if she says hi back and kinda drifts off shes just being friendly