A simplified description of this cycle is easy to understand.
When muscles are in flexion they can eventually become ischemic (lack of blood).
Ischemic muscles cause pain.
When there is pain the muscle reacts by going into spasm thinking it is protecting itself.
This causes more ischemia, pain from the ischemia, and then more spasm.
In order to break this cycle the muscle needs to be released and reset.
NMT (Neuromuscular Technique), PNF (Proprioceptor Neuromuscular Facilitation), and other reflexive treatments are facilitated and the cycle can be broken.
Tight muscles are swollen and affect surrounding soft tissue structures such as nerves.
I reset the muscle spindles and elongate the piriformis and take it out of that awful cycle and away from the underlying sciatic nerve.
This can be done on any accessible muscle stuck in hypertonicity or a state of tension promoting the pain-spasm-pain cycle.