Dear Friends,

We are receiving a few questions about Stuart McGill, a Professor at the University of Waterloo in Canada, and his theory on core strengthening.

We wanted you to have a current explanation, so you can understand where STOTT PILATES fits in, and be prepared to answer any questions that may come to you about this particular approach.

As an organization, STOTT PILATES does its best to stay on top of the most current, scientific research available. We make sure anything we teach in our courses and workshops is backed by this research. We also want to ensure that the research we quote is supported by a number of different proponents in a number of different areas. As part of this, we are very aware of the teachings of Stuart McGill.

It seems as though Mr. McGill’s viewpoints have attracted quite a bit of attention lately. His article deals with Pilates instructors who "pull in the stomach", "press the lower back into the Mat", or "hollow out the abs". On the contrary, STOTT PILATES instructors teach connection of the pelvic floor, transversus abdominus and lumbar multifidus at a sub‑maximal contraction, in a neutral pelvic alignment to ensure the proper muscular firing pattern which will provide support of the structures before enlisting the larger superficial muscles.

Although modified Pilates exercises are often used in a rehabilitative as well as post‑rehabilitative setting, it is important to recognize the place it holds within these modalities. Pilates is most effective when integrating the injured part into movement of the body as a whole. As such, we must work to address a number of different issues when working with the same individual. In all of our teachings we encourage looking at each client as a very unique situation, with specific strengths, weaknesses and requirements.

To address Mr. McGill’s point about movements that are detrimental to the spine, we always have to consider that people’s day-to-day lives require that they move in all directions, including flexion, extension and rotation. It is generally agreed that flexion and extension, especially when combined with rotation, put stress on the structures of the spine. However, we are also obligated to recognize the need to strengthen a healthy spine and all its support structures for enough mobility and stability to be able to perform these actions without risk of injury.

The STOTT PILATES approach draws from many sources including Lee, Vleeming, Richardson, Hodges, Hides, Jull, Janda, Sahrmann, Comerford and Levangie among others (a full reference list is available if you are interested). We have done our best to incorporate the findings of these pre-eminent researchers whose work is substantiated with clinical research. 

In general, there are a number of areas we need to make sure are being addressed with each client individually. The idea of working isometrically in a neutral alignment is completely sound, as it trains the muscles of the core (including all layers of abdominal musculature as well as the complete complement of spinal muscles) to support the torso in the most biomechanically strong position. Looking at the full repertoire of STOTT PILATES exercises, a great number of them tax the body in an isometric fashion as well as in a wider range of movements. As well-designed, efficient beings, we need to be able to move in all planes of motion as well as resist rotation and control the spine, as the arms and legs move in functional directions. Therefore, it is important to stabilize the spine both tonically and isometrically.

With STOTT PILATES training, we are attempting to gain mobility with stability, meaning we want to allow dynamic movement while being able to control that movement without risk of damage to the underlying structures.

Isometric training can help provide a great deal of stability against outside forces as long as the deep segmental control is trained and strong. If there is too much compression or shearing force, and the individual vertebrae are not stable in relation to each other, the ability of the spine to withstand these forces is inadequate and could result in strained ligaments and over‑approximation of the bones, which may result in the break-down of articular cartilage and ultimately osteoarthritis.

Currently, the STOTT PILATES repertoire teaches the theory of three levels of stabilizers at each joint. These muscles are categorized as:

  1. local stabilizers
  2. global stabilizers
  3. global mobilizers

The local stabilizers control the joint segmentally and are characterized by being close to the axis of movement, non‑direction dependant and predominantly comprised of type I muscle fibers. These muscles are activated at low loads and proprioceptive challenge and are designed for endurance. Once these muscles can provide deep inherent joint stability, then the bigger muscles that create and control movements can be challenged.

Global stabilizers are required when loads are increased and more control is required. They are larger muscles that often work eccentrically to control range of motion.

Global mobilizers are the large, more superficial muscles that provide the power for explosive movements. They respond forcefully to higher loads.

In order to effectively prepare a body for functional activities, all levels of muscles must be addressed. When we refer to the core, we must include training of all muscles including the transversus abdominis, internal and external obliques as well as the rectus abdominis and the various layers of spinal extensors from the deep multifidus to the larger iliocostales. Training only locally or globally is ineffective. All three systems must be trained in proper succession to be successful.

In terms of rotation, structurally and biomechanically, there is more rotation available at the thoracic spine compared to the lumbar spine: The lumbar is much better suited to flexion and extension. Not allowing thoracic rotation will impede functional muscle patterns in both rotation and shoulder girdle movement. Previously it was common to teach rotation in a seated position where the pelvis did not move and all the rotation occurred above the L5-S1 junction. We now encourage slight movement of the pelvis toward the direction of rotation to decrease the shearing forces at this joint and allow the rotation to continue smoothly through the entire spine. We need to be constantly aware of the spine moving evenly in any direction, without encouraging gross movements at a joint where less stabilization exists. It does not make sense for us to continue increasing range of motion and potentially create an unstable hypermobility in a location that does not have the strength to control that motion.

The argument over doing lumbar flexion exercises from a seated or supine position is interesting. In our discussions we must bring up the psoas paradox which refers to the hip flexors acting as lumbar extensors if they are short or facilitated. If they are the dominant muscle, then exercises such as the Roll Up or Teaser would definitely put the lumbar spine into a vulnerable position. If you or your client has the appropriate length/strength balance between the abdominals – particularly rectus abdominis and obliques – and the psoas, then the lumbar spine is able to flex and move appropriately. If not, the lumbar spine would be placed under considerable compression and would be vulnerable to injury.

One of the foundations of STOTT PILATES is that exercises can be appropriately modified for any client at each stage of recovery and beyond. The trick is to not paint with broad brush strokes, but pay much more attention to the details and make sure the program choices are appropriate for each individual in each situation. This will include deciding when to work tonically with a focus on mobility or work isometrically and challenge stability. When working with a group, a more conservative approach may be best, keeping in mind that the method was designed to exercise the body in all planes of motion.

Hopefully this information is useful to you and is helpful to clear up some of the confusion you may have. The new STOTT PILATES Injuries & Special Populations Support Material manual goes into quite a bit more detail on many of these issues. It may be useful to add to your library if you do not already have it. If you have not yet taken the ISP course, it is highly recommended, as it will give you a better depth of understanding in many of these areas. If you still have questions or concerns we would be more than happy to address them.

Thanks for your continued support of STOTT PILATES and we will do our best to remain at the forefront of training and certification in the industry. 

With best regards,

Yours in health,

Lindsay G. Merrithew
President and CEO

Moira Merrithew
Executive Director, Education

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