Due to health conditions, i do cardio 60 min/day every day. dumbbell weight training 3x/week. Vegetarian by bringup, didnt try anything new nutritional, because no one suggested.
a sleep specialist told me, i am ovetthinking and i cannot will sleep into existence. He recommended that i do cbt-i. He emphatically ruled out physical tiredness does not necessarily mean mental tiredeness. As i mentioned cbt-i for most part worked, but when the next day there is a significant event, i cannot sleep a wink. I was told (by my primary) to take some anti anxiety pills that did not help much. i dont like sleeping pills as i feel groggy next day almost as if i never slept, even melatonin has that effect.
Also after wearing my Garmin to gauge heart rate and sleep effectiveness I found refined carbs eaten late in the evening keep me up at night.
So might be worth experimenting and seeing if anything effects your sleep positively.