Lyn W. Freeman
We live in a highly stressful culture that has contributed to the development or exacerbation of stress-related illnesses. Stress-related diseases include cardiovascular disease, hypertension, gastrointestinal disorders, anxiety, and depression. When stressed, we also experience pain more intensely because we block our body's natural opioids. Learning to relax on command can reduce the destructive effects and the symptoms of stress-induced illnesses and improve the quality of life. This chapter describes the somatic methods of deep relaxation that were originally developed as medical interventions.
In 1905, Edmund Jacobson discovered that being very relaxed hindered the elicitation of the startle reaction, which is the sudden jerking reaction to loud noises. His discovery proved to be the first systematic study of the effects of relaxation on the body. In 1938, Jacobson further noted that chronic sustained tension of skeletal muscles increased the amplitude of reflexive responses while decreasing their latency. Jacobson eventually concluded that detailed observation and introspection of the body's kinesthetic sensations and the mental processes accompanying them were necessities for accomplishing complete relaxation.
Jacobson developed a systematic method for relaxing all the muscles of the body. This somatic relaxation method, called Jacobson's Progressive Relaxation Therapy (JPRT), was very time consuming, often requiring 100 or more practice sessions to master. Students targeted one major group of muscles at a time, learning to recognize—more and more—subtle tension cues and relax them away.
Because the time commitment was not palatable for most persons in need of training, Joseph Wolpe developed a method called Abbreviated Progressive Relaxation Training (APRT), which focused on relaxing several muscle groups simultaneously during one session. Wolpe's method allowed practitioners to become reasonably proficient at relaxation in as few as ten training sessions.
In opposition to the teachings of Jacobson, Wolpe taught students to tense muscles and then relax them, as opposed to simply observing existing tension and then relaxing it away. Other researchers eventually developed more abbreviated methods of their own that varied in application, sometimes adding strong cognitive components to the relaxation protocol.
Research on the physiologic effects of APRT demonstrated that relaxation practice blunted the excitatory autonomic changes experienced in response to everyday life events. APRT accomplished this effect by modulating both arms of the autonomic cardiovascular control systems (i.e., sympathetic and vagal). Relaxation also induced the release of endogenous opioids. These opioids are partially responsible for the reduction of circulatory stress reactivity that occurs in response to relaxation practice. The practice of relaxation was discovered to improve immune competence, especially in older populations, who often experience a loss of immune function.