Shoulder pain. A 2017 study published in the Journal of Physical Therapy Science reports that shoulder pain is one of the most common musculoskeletal disorders, affecting as many as 66.7 percent of the population. The study goes on to say that massage therapy can often help reduce this type of pain, sometimes in a matter of days, though 36 sessions appeared to offer the greatest level of relief.
Massage has been shown to reduce neuromuscular excitability by measuring changes in the Hoffman's reflex (H-reflex) amplitude. A decrease in peak-to-peak H-reflex amplitude suggests a decrease in motoneuron excitability. Others explain, "H-reflex is considered to be the electrical analogue of the stretch reflex...and the reduction" is due to a decrease in spinal reflex excitability. Field (2007) confirms that the inhibitory effects are due to deep tissue receptors and not superficial cutaneous receptors, as there was no decrease in H-reflex when looking at light fingertip pressure massage. It has been noted that "the receptors activated during massage are specific to the muscle being massaged", as other muscles did not produce a decrease in H-reflex amplitude.