Trigger point therapy is a modality that specifically targets the muscles that are hurt and inflamed.  This pain can be felt in the muscle belly, but it can also be referred to other areas of the body.  Trigger points can be the size and shape of a pea, to a stretched out rubber band.  A trigger point will actually shorten your muscle.  Then tension can be felt in the origin and insertion of that muscle.

There are several types of Trigger Points:

• Active - These are found locally, or referred pain is found in a different part of the body.
• Latent - This trigger point is there, but isn't referring pain yet. You possible can feel this one when the actual muscle that it resides in is strained or pressured
• Key - The pain is referred down a nerve pathway. Sciatic is an example of this.

Trigger points and the activation of trigger points are caused by: 

• Muscle overload (acute and chronic)
• Direct trauma to that muscle
• Stress (emotional and physical)
• Infection
• Postural imbalances
• Disease

Some of the ways to release Trigger points are manual pressure, using fingers, elbows, feet and various tools.  Also stretching, vibration, and tapotement are very effective.