I notice sometimes that after I do a good workout and/or go to work I have some difficulty falling asleep. So I have developed my own nightly routine which usually involves some sleepytime tea. I also add in some valerian root an hour before bed. This routine helps me a lot to fall asleep.
9 Things All Runners Should Do Before Bed is an incredibly informative article from Active.com . Check it out, it may help you get better sleep. Until next time, keep eating your greens!