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Key muscles of the intrinsic stabilization subsystem (ISS): transverse abdominis, diaphragm, multifidus, and pelvic floor.

Intrinsic Stabilization Subsystem (ISS)

The intrinsic stabilization subsystem is comprised of the transverse abdominis (TVA), internal obliques, pelvic floor, diaphragm, multifidus, and abdominal fascia (posterior layer), which is continuous with the investing fascia of the diaphragm and pelvic floor.

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Course Description: Intrinsic Stabilization Subsystem

This course describes the intrinsic stabilization subsystem (ISS), a concept originally proposed by Dr. Brent Brookbush to integrate the work of professionals such as Vleeming et al. (1), Hodges et al. (20), Bergmark, A. (1989), Comerford and Mottram (2001), etc. This subsystem may also be referred to as intrinsic core muscles, deep core muscles, intrinsic stabilizers, stabilizing system, local stabilizers, and is related to the terms muscle sling, myofascial sling, myofascial synergy, core subsystem, myofascial lines, myofascial trains, anatomy trains, myofascial meridians, and deep front line.

The Intrinsic Stabilization Subsystem is comprised of:

  • Transverse Abdominis (TVA)
  • Internal Obliques
  • Pelvic Floor (Levator ani, coccygeus, and associated fascia)
  • Diaphragm
  • Multifidus
  • Rotatores, Interspinales & Intertransversarii
  • Abdominal Fascia (posterior layer)
  • Continuous with investing fascia of the Diaphragm and Pelvic Floor
  • Thoracolumbar Fascia (TLF) (anterior and middle layer)
    • Potentially
      • Quadratus Lumborum
      • Psoas
  • Concentric Function: None (potentially traction/decompression)
  • Isometric Function: Stabilization of the lumbar spine, SIJ, and pelvis
  • Eccentric Function: Contributes to eccentric deceleration of lumbar flexion and lateral flexion.

Common Maladaptive Behavior

  • Under-active

Practical Application

The concepts and techniques described in this course may be particularly beneficial for neuromuscular re-education, coordination, motor pattern integration, whole-body strength, functional strength, and sports performance. Sports medicine professionals (personal trainers, fitness instructors, physical therapists, massage therapists, chiropractors, occupational therapists, athletic trainers, etc.) should consider adding these exercises to their repertoire to improve the outcomes of their integrated exercise programs, sports performance programs, and therapeutic (rehabilitation) interventions.

Pre-approved Credits for:

Pre-approved for Continuing Education Credits for:

This Course Includes:

Pre-approved credits for:

Human Movement Specialist (HMS) Certification

Pre-approved for Continuing Education Credits for:

This Course Includes:

  • AI Tutor
  • Webinar
  • Study Guide
  • Text and Illustrations
  • Audio Voice-over
  • Research Review
  • Technique Videos
  • Case Study and Sample Routine
  • Practice Exam
  • Pre-approved Final Exam

Additional Subsystem Courses

Key muscles of the intrinsic stabilization subsystem (ISS): transverse abdominis, diaphragm, multifidus, and pelvic floor.
Caption: Key muscles of the intrinsic stabilization subsystem (ISS): transverse abdominis, diaphragm, multifidus, and pelvic floor.

Study Guide: Intrinsic Stabilization Subsystem

Lecture: Review of Core Subsystems

Introduction: Intrinsic Stabilization Subsystem

Research Corner
9 Sub Sections

Summary of Research Findings

Practical Application
5 Sub Sections

Videos: Isolated Activations
7 Sub Sections

Videos: Reactive Activation
2 Sub Sections

Sample Program: Anterior Pelvic Tilt

Bibliography

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