This would prevent snoring and making their position known to the enemy.

这能防止他们打鼾，避免让敌人知道他们的位置。

So, I figure a sleep posture that promotes good sleep quality would have to (1) Prevent snoring and (2) at least not impede the glymphatic system.

一能防止打鼾，二能至少不妨碍类淋巴系统的运作。