The psoas muscle is not just a physical structure; it’s deeply intertwined with the nervous system, including the sympathetic (SNS) ("fight or flight") and parasympathetic (PNS) ("rest and digest") branches. The vagus nerve (VNS), a major component of the parasympathetic nervous system, plays a crucial role in calming the body after stress or perceived threat. A tense psoas can signal the nervous system to stay in a state of heightened arousal, potentially hindering the body's ability to fully relax and recover. A tight psoas can restrict the movement of the diaphragm, leading to shallow, chest-breathing and subsequent engagement of the SNS. The psoas muscle is believed to store emotional and physical stress, potentially becoming chronically tight in response to trauma or prolonged stress and releasing the psoas through targeted exercises and practices can help to release held tension and promote emotional regulation. Practices like yoga, somatic movement, and deep breathing can help to engage the Vagus nerve and promote relaxation, indirectly influencing the psoas and its connection to emotional well-being. In essence, the psoas and Vagus nerve are two key players in the body's stress response and overall regulation. By understanding their connection, we can better understand how to support the body's natural healing and relaxation mechanisms.