[j_mo]

Never worked for me, I think if you're physically fit, being physically tired has no correlation on sleep. Since 12y/o I've struggled to sleep before 1-2am, and since 14y/o I've exercised a frankly ridiculous amount.

14-18yo I went to the gym 1hr/day every weekday, boxing 1-2hrs 3x/wk, karate 1hr 2x/wk.

18yo+ I've boxed, run 30-40 miles/wk (some 3/4hr runs in there too leading up to ultras), climbed 2-10hrs/wk, and gym 2-3x/wk for the last 5 years although that schedule and activity level has varied since I have no real reason to kill myself training now that I don't compete in anything.

None of the above have an impact on sleep or ability to fall asleep, I have taken weeks off due to injury or months off due to burnout after a 12hr race, and my sleep schedule hasn't changed. Still tired-ish around 5-7, then 7-2am find it impossible to fall asleep, followed by 5-6hrs sleep and repeat. I 100% agree with the guy who replied to you that got heavily downvoted that "just exercise" is a vastly oversimplified response to the complex issues most people have with sleep. Not everybody's sleep issues are due to an inactive lifestyle, and I'd bet that is not the case for the majority of people.