A late workout shouldn’t hinder your sleep. It could even help
washingtonpost.com
washingtonpost.com
Exercise increases cortisol, cortisol increases wakefulness. Cortisol is, in fact, the very hormone that makes you wake up in the morning.
I do agree that exercise increases your quality of sleep. I've found that it improves my sleep so much that I don't need nearly as much of it. But that's a separate question from whether it delays the start of sleep.
If you just started out (less than two weeks, 4 days/week) then it will make you more awake.
If you passed this point then there is enough fatigue accumulated that your body just wants to rest/sleep. I would still recommend to finish training 3-4 hours before sleep.
Edit: actually .. scratch that .. I should have an option on HN to not see paywalled links. Can someone on the dev team make that happen?