What Is A 'Trigger Point'?

Image from Chicago School of Canine Massage

A trigger point is a small patch of tightly contracted muscle tissue that is painful when pressed and cause a shortening of the muscle fibres. Often the patch of muscle chokes off its own blood supply, which irritates it even more.

Trigger points lead to an increase in muscle stiffness and tenderness and a decrease in range of motion. In addition, the discomfort from trigger points can radiate from the point itself and cause referral pain in other parts of the body.

Trigger points can occur in several ways – for example, repetitive overuse injuries, sustained loading, habitually poor posture, muscle clenching and tensing due to mental/emotional stress, direct injury, and from inactivity.