The Stott Pilates method encourages a neutral pelvis as much as possible (Viola, 2013). However, when legs are raised when lying on the back, or when there is loss of stability, one should aim to imprint the pelvis to stabilize the pelvis and protect the lower back. For a beginner Pilates practitioner, one should imprint the pelvis whenever legs are raised in the air. Over time, as the practitioner grows stronger, they can aim to perform the same exercises with a neutral pelvis.
The pelvic region holds the largest percentage of the body’s weight load, and it is therefore important to stabilize the pelvis (Isacowitz & Clippinger, 2011). In a neutral pelvis position, the pubic bones (Pubic symphysis) and pelvic bones (hip bones/ Anterior Superior Iliac Spine) are level, and the lower back (lumbar spine) retains its natural curve. When a person lies on their backs in a neutral position, there will be a slight curve in the lower back. Naturally and anatomically, there is a slight curve in the lumbar region. This position allows the discs between the vertebrae of the spine to do their job of cushioning the vertebrae and not allowing bone to grate on bone. Neutral position is the most stable and shock-absorbing position that we can put our pelvis and lumbar spine in; therefore, it is the ideal position for people to be in, not only in Pilates class but also in their daily lives (Think Pilates, 2008).
In pelvic stabilization, the individual should aim to imprint the pelvis. This position is generally used for certain body types, and is also used in the beginning to ensure stability of the pelvis and lumbar spine region if neutral position cannot be maintained. This position is also ideal for stabilizing weak abdominal obliques, with neutral being the ideal future goal. When a person is lying down in imprinted position, there is no gap between the lumbar region and the floor. It is important to note that the low back is not jammed into the floor; rather it is lengthened and almost parallel to the floor. To imprint the pelvis, a person has contract and shorten the external obliques and transverse abdominals, which will draw the lower ribs down toward the hip bones, pressing the lower back on the floor. An imprinted pelvis prevents an individual from arching their back, or overworking the back muscles, and ensures engagement of the core muscles to bear the load (of the exercises. It is important to appropriately contract the Transversus Abdominals, and refrain from contracting the Rectus abdominals, to maintain better lumbo-pelvic control. The dynamic control of trunk muscles (Rectus, Rransversus, external obliques, internal obliques) plays an important role in preventing repetitive injury of intervertebral disks, facet joints, and related structures (Queiroz, Cagliari, Amorim, & Sacco, 2010).
Muscles activated in imprinted pelvis: multifidus muscle, external obliques, internal obliques, transverse abdominal
Muscles not activated in imprinted pelvis: Gluteus maximus, Rectus abdominis
Figure 1. Diagram of skeletal system in three different pelvic positions
A. Neutral Pelvis
B. Imprinted Pelvis
C. Pelvic Tilt (wrong position)
(Body IQ Pilates, 2013)
Body IQ Pilates (2013), from http://bodyiqpilates.wordpress.com/
Isacowitz, R., & Clippinger, K. (2011). Pilates anatomy Champaign, IL: Human Kinetics.
Queiroz, B. C., Cagliari, M. F., Amorim, C. F., & Sacco, I. C. (2010). Muscle activation during four pilates core stability exercises in quadruped position. Archives of Physical Medicine and Rehabilitation, 91(1), 86-92. doi: http://dx.doi.org/10.1016/j.apmr.2009.09.016
Think Pilates (2008). Pilates Basic Principle – Pelvic Area, from http://thinkpilates.com/pilates-basic-Viola, L. (2013). The 5 Basic Principles, from http://formandfunctionpilates.com/blog/?cat=7