If what you're experiencing is what I think it is....

These hot spots (in PT we call them trigger points) are areas with a high concentration of nerve endings, particularly those that help to regulate overall muscle tone, (muscle spindles). When there is an irritant in the muscle, eg all the lovely things that cells release related to activity, especially increased activity, a neurological feedback loop gets kicked into play and you end up with trigger points. They are a reflection of irritation in the muscle.

Foam roller techniques work well. So does The Stick

www.thestick.com

and trigger point release therapy

http://www.polardiscount.com/scripts...FQkegwodpAaoeA

The under lying cause is often a muscle imbalance or biomechanical issue that can be diagnosed by the appropriate healthcare professional.