We have also suggested
elsewhere that stimulation of pressure receptors and the resulting
increase in vagal activity and serotonin levels (the body's natural
pain suppressor) is one potential underlying mechanism for pain
relief [15]. A related mechanism we have discussed is based on
substance P decreases [substance P causing pain] following massage
[15]. Further research is clearly needed to explore the potential
underlying mechanisms for the relief of knee pain and other pain
syndromes following massage therapy. In addition, this protocol
needs to be replicated on a more representative sample than the
health-care employees sampled here, which is a limitation of this
study.