The Deep Longitudinal Subsystem is one of four common muscle
synergies used by the body during exercise and other movement.
Stretching down the back and legs, it’s a combination of
muscle groups, membranes and ligaments, including the erector spinae,
thoracolumbar fascia, sacrotuberous ligament, bicep femoris.
The
origination and insertion of the Deep
Longitudinal Subsystem
As a major muscle synergy, the Deep Longitudinal Subsystem
has several points of origination and insertion.
The uppermost part is the erector spinae, which comprises
three muscles: the illiocostalis, the longissimus and the spinalis. These
originate and insert at various points between base of the skull and the
cervical transverse processes.
Other muscles in the system originate and insert at various
points in the back, hips and legs.
The action
and basic functional movement of the Deep Longitudinal Subsystem
The Deep Longitudinal Subsystem works alongside three other
muscle synergies:
The Lateral Subsystem
The Posteriour Oblique Subsystem
The Anterior Oblique Subsystem
Personal trainers and other fitness professionals should be
aware of how these four systems work together as one unit during exercise, each
having its part to play.
The muscles and ligaments in the Deep Longitudinal Subsystem
group transfer kinetic energy up the legs and above the pelvis, allowing you to
walk, jog and run. They also help you bend forwards, squat and lunge, as well
as carry out other contralateral movements in the sagittal plane, which divides
the left and the right side of the body from the back to the front.
The Deep Longitudinal Subsystem helps to stabilise the
sacroiliac joint (SIJ), which is found between the sacrum and the pelvis.
Support in this area is important to avoid back pain. It also acts to stabilise
the whole of the back, core and hips.
Problems
associated with the Deep Longitudinal
Subsystem
Because it covers such a large area of the body, there are
many issues that can arise through problems with the Deep Longitudinal
Subsystem. These range from joint pain and restricted movement in the neck,
back, hips and legs to lack of stability in the core.
As so many people suffer from back pain, it’s worth
remembering the importance of this system in supporting and allowing movement
in the back. In particular, those who spend a lot of time seated at a desk
might encounter problems when they then use their legs during sporting
activities or at the gym, in particular when squatting or deadlifting. This can
be eased by using a foam roller after being seated and before a work out.
Exercises to strengthen
the Deep Longitudinal Subsystem
Exercise that activates the whole group of muscles in the Deep
Longitudinal Subsystem can help strengthen its component parts. These include:
- Squats
- Bent leg deadlifts
- Alternating forward lunges
- Anterior lunges with reach at knee height
- Alternating power step-ups
- Hip hinges with overhead lift
- Bridge and curl
Static stretches for the back muscles,
hip flexors and hamstrings are also helpful.
