There have been anecdotal reports of yoga helping with sleep. Some yoga poses can be particularly relaxing.
Another pose found on page 65 of the book Healing Pain and Injury by Maud Nerman is called “Legs Up the Wall” where you lie flat on your back with legs up against the wall at 90 degrees. And then put your hands over your head on the floor. It writes …
“This pose is so relaxing! … It can be done to help you sleep.”
This pose is also on of the six poses mentioned by Best Health in the article 6 soothing yoga poses to help you sleep. Although they call the pose Viparita Karani. If this pose is too difficult to do, you can do with leg on a chair instead of against the wall. The trick is to have your legs higher than your head. Possibly could it be the increase blood and oxygen flow to head helps?
For some scientific credibility, Psychology Today reports in its article Yoga Can Help With Insomnia of a study showing yoga improving sleep.