ABSTRACT Fascia and the autonomic nervous system (ANS) interact through a dynamically integrated regulatory relationship shaped by neural and physiological processes and by their coevolution across vertebrate phylogeny. Despite this, the implications of this relationship remain under-integrated in both fascia research and clinical practice. This article presents a polyvagal framework for understanding fascial tone and therapeutic change, drawing on the keynote address delivered by Stephen W. Porges, PhD, at the 2025 Fascia Research Congress in New Orleans, Louisiana, and an extended interview conducted in February 2026.

ABSTRACT Polyvagal theory is reviewed in a short introduction, followed by a conversation with Dr. Stephen Porges. Porges’s history as research director with the Rolf Institute® (now the Dr. Ida Rolf Institute®) is discussed, as well as his body perception questionnaire, the term neuroception, and how Rolfing® Structural Integration can be polyvagal-informed.

From “Physical Therapy”From “Physical Therapy”From “Physical Therapy”From “Physical Therapy”From “Physical Therapy”The effects of soft tissue manipulation (Rolfing method) were evaluated on young healthy men using two dependent variables: 1) angle of pelvic inclination and 2) parasympathetic activity. Pelvic inclination was assessed by determining the angle of standing pelvic tilt (SPT) with an inclinometer. Autonomic tone was assessed by a measure of cardiac vagal tone (amplitude of respiratory sinus arrhythmia) derived from monitoring heart rate. Thirty-two subjects, pre-selected for exhibiting an anteriorly tilted pelvis, were randomly assigned to either an Experimental Group (n = 16) that received a 45-minute Rolfing pelvic mobilization session or a Control Group (n = 16) that received a 45-minute control session without manipulation. Dependent variables were assessed before the 45-minute session, immediately after the session, and 24 hours later. Comparing pretest to posttest assessments, the Experimental Group demonstrated a significant decrease in SPT angle and a significant increase in vagal tone. The Control Group did not show significant pretest or posttest differences. The results provide theoretical support for the reported clinical uses of soft tissue pelvic manipulation for 1) certain types of low back dysfunction and 2) musculoskeletal disorders associated with autonomic stress.