The Effect of Repeated Tense‐Release Sequences on EMG and Self‐Report of Muscle Tension: An Evaluation of Jacobsonian and Post‐Jacobsonian Assumptions About Progressive Relaxation

Abstract

ABSTRACT This study tested three psychophysiological hypotheses generated from assumptions underlying post‐Jacobsonian progressive relaxation techniques and assumptions that conflict with the rationale for Jacobson's progressive relaxation method. Twenty‐eight subjects tensed and released tension from the forearm extensor and frontalis muscles during a series of trials interspersed with intervals of relaxation. Correlations between self‐report of tension and EMG were moderate during relaxation, but did not increase across successive tense‐release trials, thus indicating no increase in self‐awareness of muscle tension. As predicted by Jacobson, paying attention to either muscle produced increased tension in the frontal area, but Jacobson's prediction of increases in forearm tension while paying attention to the forearm was not confirmed. Evidence was equivocal for the existence of the “pendulum effect” predicted by Bernstein and Borkovec. Tense‐release trials produced gradual decreases in frontal EMG, but no changes in forearm EMG. Declines below baseline in self‐reported muscle tension occurred only several minutes after the end of the tense‐release trials, and did so for the forearm despite lack of EMG decreases in that area. This finding may reflect the influence of cognitive rather than muscular processes.