‘Butt clenching’ and ‘tail tucking’ are generally habitual motor responses resulting from an instruction to tighten the gluts or squeeze the butt as part of an exercise programme. Or, for others it’s simply an adaptive posture. The problem is that the resulting chronic adaptive shortening of the inferior myo-fascial structures often leads to back pain.

 

 

 

Take the example the lady in photo 1, you can see by the photo she habitually shifts her pelvis forward and tucks the tail to hang off the iliofemoral ligaments. This results in little activity of the glutei, but an adaptive chronic shortening of the posterior inferior myo-fascial structures making eccentric lengthening of the gluteals and hamstrings in forward bending almost impossible.

Photo 2 is of a chronic active ‘butt–clencher’. What becomes obvious in these people is increased muscle tension and tightening of the posterior inferior myo-fascial structures which control the pelvis and hip – including the glutei and deep hip external rotators. Consequently, their eccentric lengthening becomes more difficult. Here you will also note the legs are abducted and stiffened.

In both scenarios this tightening of the ‘outer’, posterior and inferior myofascial tissues around the pelvis narrows the posterior inferior pelvis –  the sit-bones are drawn together – which results in an ‘out-flaring’ of the superior bowl of the pelvis placing the sacro-iliac and the lumbo-sacral joints in a vulnerable position. This ‘inferior tethering’ of the posterior structures of the pelvis, as mentioned above, results in an inability of these tissues to eccentrically lengthen – shifting the fulcrum of movement from the hips to the back – thereby adversely loading the spine over time.

To counter these habitual patterns, clients need to learn how to control their hip-pelvis unit and use the First Fundamental Pattern of the Pelvis to shift the pelvis back, and flex the hip with lengthening of these posterior inferior myo-fascial structures.

This active eccentric lengthening of the glutei, combined with a co-activation of the Lower Pelvic Unit, enables not only good hip/pelvic myo-mechanics, but also protects of the spine through movement.