My chronic insomnia is "primary" meaning it persists in the absence of other factors. I'm not depressed. I get enough sun exposure. I take my supplements. I have a comfy mattress. I practice good sleep hygiene. I use blue light filters and don't use my phone/computer before bed. I exercise every day. I eat well and not before bed. I don't have breathing issues. Nothing helps. It's just the hand I was dealt genetically.
Furthermore, exercising to the point of exhaustion is reckless and I've injured myself over the years doing exactly that because I don't get enough sleep for my body to recover properly.
I can run and stay aerobically fit and I played high level soccer for many years when I was younger without too much issue, but activities like weightlifting are a struggle for me. Benchlifting when you're sleep deprived is pointless so I have to fill in on my off days.