Deep Longitudinal Subsystem (DLS)

This course describes the deep longitudinal subsystem (DLS), a concept originally proposed by Vleeming et al. (1). The deep longitudinal subsystem may also be referred to as the deep longitudinal sling, deep posterior subsystem, deep posterior sling, deep posterior myofascial synergy, and is similar to the concepts of body slings, muscle synergies, myofascial lines, myofascial trains, anatomy trains, superficial back line, and spiral line.

The Deep Longitudinal Subsystem (DLS) is comprised of:

• Splenius Capitis and Splenius Cervicis
• Rhomboids
• Erector Spinae
• Thoracolumbar Fascia (Deep Posterior layer)
• Sacrotuberous Ligament
• Biceps Femoris
• Adductor magnus
• Piriformis
• Obturator internus (and deep hip external rotators)
• Head of Fibula
• Fibularis Longus

Function (Brief)

• Concentric Function: Assists with propulsion from heel strike to push-off during gait, assists with lifting from a forward bent position, and is the prime mover of lumbar hyper-extension.
• Isometric Function: Contributes to stabilization of the tibiofibular joints, hip joints, sacroiliac joints, and all segments of the spine.
• Eccentric Function: Decelerates leg swing and impact during heel strike, eccentrically decelerates forward bending, and eccentrically decelerates ankle inversion.

Common Maladaptive Behavior

• Over-active

Practical Application

• Release (self-administered, vibration, or manual):
  • Erector Spinae
  • Rhomboids
  • Splenius Capitis and Splenius Cervicis
  • Biceps Femoris
  • Adductor magnus
  • Piriformis, Obturator internus (and deep rotators)
  • Fibularis Longus
• Core
  • Avoid exercises that focus on strengthening the erector spinae , adductor , and/or hamstring .
• Integrated Exercise
  • Avoid straight-legged deadlifts and kettlebell windmills.

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:

• Human Movement Specialist (HMS) Certification

Pre-approved for Continuing Education Credits for:

• Athletic Trainers
• Chiropractors
• Group Exercise Instructors
• Occupational Therapists
• Personal Trainers
• Physical Therapists
• Physical Therapy Assistants
• Yoga Instructors

This Course Includes:

• AI Tutor
• Video Lectures
• Study Guide
• Text of Material
• Learning Activities
• Practice Exam
• Pre-approved Final Exam

FAdditional Subsystem Courses

• Intrinsic Stabilization Subsystem (ISS)
• Anterior Oblique Subsystem (AOS)
• Posterior Oblique Subsystem (POS)

Caption: Deep Longitudinal Subsystems (DLS): Fibularis (peroneal) muscles, biceps femoris, sacrotuberous ligament, and erector spinae.