Re: Evening Workouts
A PM workout would be a workout in the afternoon or evening (as opposed to a morning workout). He's referring to the clock (AM before noon, PM after noon).
I have occasionally done a workout after 8:00pm and find it hard to wind down.
I really enjoy a 5:00pm workout, though. After work, before dinner. That makes my evening more a useful part of the day instead of feeling sluggish. I feel that I sleep better if I've had a good, exhausting workout before dinner.
My input is subjective and anecdotal, but I would say a workout three or more hours before sleep won't decrease sleep quality.