Unlike many members of my family who can fall asleep regardless of the circumstances, I need to feel sleepy/tired to sleep. I'm fairly fit, so getting to that s

Unlike many members of my family who can fall asleep regardless of the circumstances, I need to feel sleepy/tired to sleep. I'm fairly fit, so getting to that state with a job that involves me sitting at a desk can be a challenge. When I do sleep, I sleep pretty well, but getting to that state can be tough. I simply have to do some physical work each day to tire my body - otherwise, sleeping is near impossible. The gym is often not enough (and if I go in the evening, it actually wakes me up). I find I need to do something moderately strenuous and mundane, like carrying a few groceries for a mile or two, or maybe sweeping + mopping a few floors round the house or perhaps some DIY. Also, if I'm unable to sleep, rather than trying to sleep, I find it's better to get up and do some work, even if means being in front of a screen. That knocks me out eventually!