Today’s blog is on the Lateral Subsystem group of muscles. These give
stability to the frontal plane and the sacroiliac joint (SIJ), aiding balance
and keeping the pelvis in alignment during single leg movements such as walking,
running or climbing stairs.
The Lateral Subsystem comprises the following:
Quadratus lumborum
Gluteus medius
Tensor fascia latae (TFL)
Adductor complex
The
origination and insertion of the Lateral Subsystem
Because it is a major muscle synergy, the Lateral Subsystem
has various points of origination and insertion as follows:
Quadratus lumborum –
originates at the iliac crest of the pelvis, inserts at the 12th rib
Gluteus medius –
originates at the outer surface of the ilium, inserts at the greater trochanter
of the femur
Tensor fascia latae (TFL) –
originates at the anteriour iliac crest and inserts at the iliotibial tract
Adductor complex –
originates at various parts of the spine and pelvis and inserts at points along
the femur and tibia.
The action
and basic functional movement of the Lateral Subsystem
The Lateral
Subsystem is one of four muscle synergies that are used by the body
during movement; the other three are:
The Deep Longitudinal Subsystem
(see our previous
blog)
The Posteriour Oblique Subsystem
The Anterior Oblique Subsystem
The action and basic functional movement are carried out in
the frontal plane and include gluteal rotation, leg abduction and adduction,
and stabilisation of the lumbar, pelvis and femur.
Problems
associated with the Lateral Subsystem
These can include:
- Lower back pain, tightness or
compression; muscle spasms
- Excessive pronation of the hip,
knee or foot
- Hip, knee or ankle pain or injury
- Tightness
and pain in the iliotibial band (Iliotibial Band Syndrome)
- Plantar
fasciitis (see our blog on the Plantar
Fascia)
If a personal trainer is working with a client who has excessive
pronation of the hip, knee and/or feet, this may be due to dysfunction in the
Lateral Subsystem.
Exercises to strengthen
the Lateral Subsystem
The muscles in the Lateral Subsystem can be trained in groups,
as a whole or in tandem with the other three muscle synergies. To work the
Lateral Subsystem in particular, exercises should focus on single-leg movements
and activity in the frontal plane, especially those that keep the pelvis level.
Fitness instructors and personal trainers could include any of
the following in a programme of exercise for their clients:
- Lateral lunges and lunge to
balance
- Frontal plane step ups and step
ups to balance
- Frontal plane single-leg
balance reach
- Single leg squat
- Squat with low row to lateral
lunge
- Side step downs
- Single leg passover weight
exercise
Encouraging your client to develop a strong core will also
help to support their Lateral Subsystem.
