How do you figure out which one is best for you? It seems I am tired in both the morning and at night. I am trying to optimize my sleep and health because I am working full-time and taking one college course. I cannot seem to get myself motivated or energetic enough, regardless of morning versus night. I suppose the best time for me is the middle of the day, but that is when I am working.
If you're getting normal amounts of sleep then it's probably more than likely you're not getting proper sleep, as in REM sleep. If your sleeping is disturbed and you don't get proper sleep then it's like getting less hours of sleep, because you're not really "sleeping," so insomnia can be caused by things like stress/anxiety, as well as physiological things like sleep apnea. I'd recommend getting a physical if you haven't had one in a while, it's always good to keep your health checked up on anyway. Little noises can often wake up certain people during the night too, as some are much more sensitive to sound while asleep, so white noise machines can come in handy, that emit a constant sound so any other sound wont wake you, as your ears are constantly hearing sound. Whereas if your ears are sensitive and you hear sound when it was silent most of the night, you'll wake up. I'm like this, if I don't sleep with my TV on I'll almost always wake up more than once in a night, but if I have the TV on I wont wake up at all. Stop eating at least an hour before you sleep too, as sleep causes your metabolism to be active, which increases brain activity during sleep. Sleep in a pitch black room, with no light whatsoever. When it's pitch black your body releases certain chemicals and neurotransmitters that make you tired, light will disrupt that and make you feel more awake, and make it harder to fall asleep. If you cut out all distractions and it still continues, then I'd advise going to your GP and explaining the issue and what you've tried to do to fix it, and he/she should be able to check if any physiological issues are causing it, otherwise it's most likely psychological. All the best.
