That is interesting. I find that training, or doing anything stimulating late in the day keeps me up. Even a single cup of coffee after two pm will have me tossing and turning.
I do like lifting early, like 5:30 am, because it wakes me up like no other. By the time night rolls around I'm good to go though. In fact I pass out most nights.
Try a hot bath followed by a cold shower after training. Helps me keep my soreness down and supposedly good for the nervous system too. Make the bath a magnesium soak if at night. Sleepy time, every time.