I'd say that the best time to drink your post workout shake would be after your workout.......if you did it before, then it would be a pre workout shake and if you had while you were still working out it would be a while working out shake...so I'd advise you to drink the post workout shake after you're done working out....but not too far after because then it might be considered a pre workout shake if you wait too long and then workout again.....
