Working out definitely helps ... no matter what time of day I do them, but especially if I do them late in the day.
The only time when my cycling seems to hinder my sleep is when I'm toward the end of a Randonneuring season and I've done a lot of rides where my sleep pattern was disrupted ... like 600Ks where I get 2 hours of sleep in the middle, or 400Ks where I have to be up at 1 am to get to the start in time, etc. If I do that sort of thing frequently enough, for several weeks after, I tend to wake up in the middle of the night and feel like I should be going somewhere.