It is well understood that a majority of the population presents with an anterior pelvic tilt 75-85% (1). There is nothing inherently bad with presenting with anterior pelvic tilt as a resting posture, in fact no static posture is any worse than any other static posture presentation. The only time anterior pelvic tilt becomes an issue is when you lose the ability to either access or stabilise in different ranges, particularly under load. Compensating towards ‘extension’ based patterns is quite common and we often see an increase in the pelvic tilt occur under load which has the potential to load the passive structures (bones, ligaments, labrum, discs etc.) of the spine and hips more so than the active structures (hip extensors musculature). When we talk about performance based outcomes of strength/ power and hypertrophy it is important to load the active structures (muscles and tendons) more so then passive structures. This active, muscular loading is what makes us stronger over time, provides the stimulus for hypertrophy and ultimately improves the expression of performance outcomes.
Adding a layer to last week’s blog on ‘Relative Joint Movements’, today’s blog will discuss loading the hamstrings and controlling the relative motions of the lumbar spine, sacrum and pelvis so you can get the most out of your hamstring strength/ hypertrophy training.
The hamstring muscles fall under the umbrella of ‘flexor’ based muscles - meaning their muscular function is to control extension moments. The hamstrings control the system’s extension through a few key actions:
Control knee extension in the deceleration of the leg in swing phase of gait cycle.
Control anterior pelvic tilt (and the relative joint motion of lumbar extension) through the action of posterior pelvic tilt.
The hamstrings, along with your anterior core (rec. abs and obliques) are one of the key muscles that control your pelvis moving towards greater ranges of anterior pelvic tilt.
The glute ham raise/ GHD is a common hamstring strengthening exercise as it forces you to control knee extension against BW and external load almost in isolation. A common mistake with the execution of this exercise is dumping the pelvis into further anterior pelvic tilt and extending the lumbar spine in an effort to move through the range required. It typically looks something like this.
You can see the loss of the relative spinal position throughout the movement, especially in the transition into the concentric/ up phase. This increase in lumbar extension brings along increased anterior pelvic tilt lengthening the hamstring at the proximal attachment, the ischial tuberosity. Moving towards anterior pelvic tilt is the same relative movement as hip flexion, both of these movements are the complete opposite of that created by the hamstrings which creates less tension generated by the target muscle! We see an extended spinal position which provides the lumbar spine erectors and lats increased ability to provide stability and force through the entirety of the movement. This combination means the athlete can load with external loads and perform confidently sets of 6+.
To improve the hamstrings ability to generate force in this exercise we must stabilise the proximal attachment and maintain the spinal curves from start to finish, reducing the body’s ability to move into extended postures. Applying the lessons from last weeks blog, we must increase the relative stiffness of the flexor muscles - serratus anterior and anterior core. This should look something like this:
We introduced a banded ‘reach’ instead of the external load to increase the ability to keep the rib cage back and down (retracted) through serratus anterior engagement. This doubles as an easy way to reduce the ability of the lats to extend the spine, as the serratus anterior directly opposes the lats in this motion (read a surplus of information on this topic by S+C GOAT - Eric Cressey). We cued an exhale at the top of the movement to draw the ribs down and pelvis up into relative posterior pelvic tilt through oblique recruitment, further reinforcing the ability to control the desire to extend the system and take tension off the hamstrings. This culminated in a very tough set of 5 reps at only BW with significantly increased hamstring tension.
If you decide to try this variation, please tag us and let us know how you go - may the hamstring DOMS be with you.