Possibly most significantly, various of your nerves that originate from the cervical spine Regulate the diaphragm,  Mental pressure: Tightening your neck muscles as you’re stressed can lead to neck pain and stiffness. Many people who tighten these muscles every time they’re stressed or agitated don’t realize they are doing it https://www.theorthopaedicandpainpractice.com/treatment-for-neck-pain-headaches/