Why yoga improves sleep quickly?

Yoga can improve sleep quickly because it directly shifts autonomic balance rather than relying only on physical fatigue. Slow breathing, longer exhalations, and mindful movement increase vagal tone and reduce sympathetic activation, lowering evening cortisol and quieting mental rumination. Unlike high-intensity exercise, which can transiently stimulate the nervous system, yoga promotes parasympathetic dominance and body–brain downregulation. That immediate nervous system recalibration is why sleep quality often improves within days rather than weeks.