To butt clench or not to butt clench?
Over the years of attending yoga classes one of the cues that bothered me the most was while in up dog, cobra, a king cobra, and especially bridge was being told to let go of the glutes. Their reasoning was it would either protect the back or it would keep the work out of the lumbar spine.
This is a misunderstanding as a whole to what role the glute max play in stabilization of the lumbar spine, pelvis, hip, knee, and ankle and the shoulder.
The glutes' role around the spine is simple, if you don’t have strong glutes you are going to extend and flex at the spine instead. Strong glutes encourage good lifting and movement techniques. Stability is not only about quantity of motion and the quality of the end feel, but about control of systems which allow load to be transferred and movement to be smooth and effortless.
The thoracolumbar fascia (TLF) and its supporting musculature bridge the lumbar spine and pelvic girdle. While it plays a significant role in stabilization of the lumbar spine, it is also significant in the transference of force from the trunk to the lower extremity; the glute max plays a global role in stability.
When the glute max and the contralateral latissimis dorsi contract this creates compression in the sacro-iliac joint (SIJ), compression creates stability. This compression approximates (closer) the posterior aspect of the innominates (‘hip’ bone) and contributes to the force closure mechanism.
The glutes' role around the sacrum is to provide stability through an action called force closure. Force closure is an outside force and is required if the joint has movement. The fibers of the glutes and hamstrings attach to the sacrum and when they contract help create this force closure for stability.
But there is also a mechanism called form closure. In the body this would be a fused joint but the closest example we have is the sacroiliac joint (SIJ), but the SIJ still has 0.2% movement. This is why the sacrum requires the additional stability from force closure created by the glutes.
The SIJ is surrounded by some of the strongest ligaments in the body. The glute max and the contralateral latissimis dorsi are a part of the posterior oblique system and is a significant contributor to load transfer through the pelvic girdle by the compression of articular (joint) structures is essential for efficient load transfer.
Weakness, or insufficient recruitment and/or timing, of the muscles of the inner and outer unit reduce force closure mechanism through the SIJ. The client/participant then adopts compensatory movement strategies to accommodate the weakness. This can lead to decomposition of the lower back, hip, and knee.
Two important groups when considering the muscles contributing to stability of the pelvic girdle:
The inner unit consists of pelvic floor, TVA, multifidus and the diaphragm. You can read more about this in my blog “Are You Breathing Properly” in more detail.
The outer unit consists of 4 systems:
1. Deep Longitudinal System: The muscles that make up this system up are erector spinae, deep lamina of the TLF. sacrotuberous ligament, the biceps femoris.
2. Posterior Oblique System: The muscles that make up this system are the latissimis dorsi, glute max and the TLF).
3. Anterior Oblique System: The muscles that make up this system are the external and internal oblique, contralateral adductors anterior abdominal fascia.
4. Lateral System: The muscles that make up this system are the glute medius and minimus, and contralateral adductors and QLO.
While it is important when learning to look at each aspect of the body in segmental parts and how the parts function, this is not how the parts work together. While necessary to consider the function of the individual parts, healing is unsuccessful without the consideration of how these parts achieve the harmonious actions.
Is there a reason or a need to exclude the glutes in a cobra, up dog or a bridge?
Never exclude when in bridge the glutes need to be on to aid in load transfer through the spine and glutes need to be on b/c biomechanically speaking one of the glutes movements primary movement is hip extension, and glute glute bridge is a quintessential extension of the hip. To let go of the glutes (commonly cued) and have the quadriceps take on the load is a mechanical disadvantage and the lumbar spine itself is driving the extension and the person will develop an injury over time.
Poses such as king cobra and cobra letting the glutes relax can help mobilize the lumbar spine and for recentralizing the discs. These two poses are where I would to encourage people who sit for long periods of time to let go of the glutes. The seated work place is the most common for people and can really mess up the mobility of the lumbar spine itself as it is in flexion for about 8-10+ hours every day. By relaxing the glutes on these 2 poses will take the work straight into the spine to create mobility and/or to recentralize the disc by minimizing the pelvic contribution. Read my articles Understanding Mechanism of an Injury & the Functional Anatomy of the Lumbar Spine and Yoga, it goes into the mechanic s of the spine & patho-mechanics of a disc bulge.
What poses would you want to make sure that the glutes are engaged?
Any of the strength based poses you want the glutes to be actively firing and in the right sequence for stability. The pelvis as a unit not only supports the abdomen but also provides the dynamic link between the spinal column and lower limbs. If we don’t encourage glute activation while moving into extension we will be teaching the participants to extend from the spine and run the risk of creating or exacerbating a condition called a spondylolysis and/or spondylolisthesis, these are extension dysfunctions of the spine. In simple terms it is a forward slippage of the vertebrae (L4 on L5 or L5 on S1). While moving into an extension based movement without the glutes coming on there is no stabile platform on which to move from and will be very painful.
Let’s look at the intricate attachments throughout the pelvis and lumbar area that the glute max has:
This muscle is the largest muscle in the body and attaches extensively to the pelvic girdle. My personal opinion is, if it’s the largest muscle in the body, it probably has a big job! Definitely go find an anatomy book or Google it to see all of the attachments as well. The attachments begin on the outer surface of the ilium behind the posterior gluteal line adjacent posterior surface of sacrum and the coccyx, the aponeurosis of erector spinae muscle (sacrospinalis), the sacrotuberous ligament, the superficial laminae of the posterior Thoraco-lumbar fascia and the fascia covering the gluteus medius muscle.
In the pelvis, the glute max blends with the ipsilateral multifidus and the contralateral latissimis dorsi through the superficial laminae of the Thoraco-lumbar fascia. Less than one half of this muscle attaches directly to the gluteal tuberosity of the femur. The remainder inserts into the iliotibial tract of the fascia lata. The IT Band helps provide the anchor for the glutes so they can activate, there needs to be about 15-20 bend in the knee to provide this anchor.
What other muscle in close proximity could the yogis really be trying to reference?
The muscle that the yogis are probably referencing is the piriformis. This little bugger likes to do lots and lots of work for the glute max and creates a multitude of problems. This muscle is in important to the stabilization of the SIJ; however, too much tension can be responsible for restricting the SIJ motion making one or both SIJ hypomobile and/or produce local pain. Since the sciatic nerve passes through and/or beneath the piriformis muscle entrapment neuropathies can occur. Other muscles that have trigger points such as the glute medius, longissimus and multifidus muscles have been reported to refer pain to the SIJ.
As we can see the primary function of the lower half of the body is to move and to simultaneously provide a stable base from which the upper extremity can function. The glutes play a critical role in the stabilization of the lumbo-pelvic-hip area. Excluding the glutes without understanding the in’s and out’s of human movement, the individual structure of the person in the pose is doing them a disservice. When teaching poses there are no absolutes, b/c we have very people that come to a group setting who fit the orthopedic profile that are all trying to get into the pose. The instructor has to be even more educated on the science of human movement, strength and conditioning and biomechanics, not just the pose.
Keep in mind who is getting into the pose; do you know their medical history? Do you know how to identify structural anomalies on a person let alone in a group setting? Build a base of understanding the movement and the person before telling them to not activate the glutes. There is the potential of neuromusculoskeletal harmony for multi-dimensional movement with a minimum of energy expenditure.
References:
Paul Chek: CHEK Institute, The Advanced CHEK Practitioner Training program
Mark Buckley: FMA Strength
Bret Contreras: The Glute Guy
Diane Lee: The Pelvic Girdle