From Discover on Google https://www.insider.com/signs-your-workout-is-hurting-you-2018-5
What is a Trigger Point?
Trigger Points (TP’s) are defined as a “hyper-irritable spot within a taut band of skeletal muscle. The spot is painful on compression and can evoke characteristic referred pain and autonomic phenomena.”1
Put into plain language, a TP is a painful knot in muscle tissue that can refer pain to other areas of the body. You have probably felt the characteristic achy pain and stiffness that TP’s produce at some time in your life.
The serratus anterior muscle is responsible for scapular and rib movement and stability. This muscle can become overloaded from poor posture of the shoulders, as well as heavy breathing from exertion. Trigger points in this muscle will cause pain to be felt under the armpit into the shoulder blade area, and down the arm into the fingers.
the sternocleidomastoid muscles are located in the front of the neck. these muscles are often overworked from prolonged sitting posture. Trigger points in these muscles are a common cause of headache pain.
trigger points are one of the most common sources of pain in the body. Once a trigger point has formed it won’t release on its own. Trigger point massage is one of the most effective way to release a point. It involves using a deep focused pressure applied directly to the knot. This frees the contracted tissue and stimulates healing.