.

.

For those of you unfamiliar with this test, essentially the objective is to look at the relative onset of firing between the glutes, hamstrings, ipsilateral and contralateral lumbar erector spinae such that in an ideal world, the relative activation of the gluteus maximus and the hamstrings fire first in relation to the erector spinae.

In light of the controversy surrounding this test, Greg Lehman, a dual chiropractor and physical therapist, provided us with an excellent post detailing the current state of the literature on this test as well as some of his thoughts on its clinical utility. In short, while he concludes in his post that for most, a delay in glute max firing seems to be the norm, activation and amplitude of firing can be modified and that abnormal activation patterns (according to this test) has yet to be proven…scientifically…to be dysfunctional.

As such, Andreo Spina also provided his thoughts on the utility of this test and described his preference for glute max testing via modification through testing at approximately 30 degrees of hip flexion. He also discussed the utility of supine bridge testing, ala Stuart McGill, in consideration of the fact that during walking, the glute max tends to “dim down” in activity during hip extension beyond 30 degrees (of flexion).

Many clinicians who utilize the prone hip extension test however, still argue that clinically relevant information can be revealed irrespective of the current state of the literature.  This is not surprising since research commonly isolates single rather than multiple variables for scientific scrutiny. Therefore, while it may be too early to throw this particular test out with the bath water, it is important that we be cognisant of the evidence and understand that hip extension motor patterns should be cross-examined via a variety of testing means such as in supine, modified prone, side-lying and upright (half-kneel and single leg stance) positions.

Half-kneeling cable lift exercise is a test

(not a great picture but it was the best I could find)

. .

This is also a test

.

Why not test AND treat?

.

No related posts.

Related posts brought to you by Yet Another Related Posts Plugin.

.

.

To answer this question, it is imperative that we must first determine whether a dysfunction is present. According to Janda, one method to doing so can be to perform a prone hip extension test to assess the quality of firing. It should be noted that this test is not to identify the the presence of a strength deficit. It is merely an assessment of quality.

To perform this test, the individual is asked to lift his or her leg up off a table in the prone position. Specific variables to take note of are the relative contribution of the, gluteus maximus, lumbar extensors and shoulder girdle. Obvious dysfunction in this pattern is present if the knee significantly flexes upon hip extension or if a “dipping” is noted in the lumbar spine indicating lumbar extension. Sean Skahan posted this video of an individual performing the prone hip extension test.

.

.

Although a positive prone hip extension test alone has limitations in identifying whether a poor performance can be attributed to a weak versus an inhibited muscle, fortunately we may be able to make this simple differentiation with a simple movement…backward walking. Dr. Craig Liebenson, author of Rehabilitation of the Spine, indicates in his text that the gluteus maximus is normally facilitated during the act of backward walking. As such, a lack of coordination during this movement (increased lumbar lordosis or an anterior pelvic tilt) indicates a weak gluteus maximus. Conversely, improved posture of the lumbopelvic complex during this movement is indicative of an inhibited muscle during the prone hip extension test demonstrated above.

Such findings have implications for corrective measures. Should an inhibited gluteus be identified, simple measures to facilitate its activation may be all that is necessary. However, should the above dysfunction be attributed to weakness, then an appropriate progressive strengthening protocol may be warranted. Below are some methods that one may use to progressively strengthen a weak gluteus maximus. (Please remember that my intention with this post is not to advocate the “training of muscles” but more so to effectively facilitate the appropriate management of an dysfunction when one is identified.)

.

Single Leg Glute Bridge

.

Half Kneeling Lift

.

Single Leg Kettlebell Deadlift

.

For maximal glute strengthening, check out this exercise by Bret Contreras:

.

Barbell Hip Thrust

.

Just announced: Dr. Liebenson will be in Toronto on April 9 & 10, 2011 to present Functional Capacity Evaluation & Performance Enhancement: A Sports Medicine Approach for Everyone.

Disclaimer: the above link to Dr. Liebenson’s text is an affiliate link to my Amazon store.

Photo courtesy of Shirley Glua / lululemon

No related posts.

Related posts brought to you by Yet Another Related Posts Plugin.

A recent study published in the Journal of Strength and Conditioning Research, examined the electromyographic activity (EMG) of various muscles during the squat exercise when performed using the Smith machine as well as using free weights. This was performed as a follow up to a 2005 study by Anderson and Behm that demonstrated higher EMG activity of the quadriceps muscles during the Smith Machine squat.

The major difference between this and that of its predecessor was that a weight equal to an 8RM for EACH exercise (to facilitate relative intensity) was utilized in comparison to a fixed, absolute weight for both exercises used by Anderson and Behm.

EMG activity was collected for the following musculature:

• Tibialis Anterior
• Gastrocnemius
• Vastus Medialis
• Vastus lateralis
• Biceps Femoris
• Lumbar Erector Spinae
• Rectus Abdominis

A relatively low “N” was used: 3 men, 3 women.  All were active in sports and familiar with the use of both free weights and the Smith machine.

The average absolute EMG activity for the free weight squat was:

• 34% higher from the gastrocnemius
• 26% higher from the biceps femoris
• 49% higher from the vastus medialis

Interestingly, no significant differences in EMG activity of the trunk musculature were found between the two exercises. I will keep my opinions to myself on this, especially when only 6 subjects were used.

Additionally, I was both surprised and disappointed the authors failed to include the gluteal musculature within this study since hip extension is one major component of the squat exercise.

My Thoughts:

These findings likely represent a increased stabilizing role of the above musculature for the hip, knee and ankle during free weight squats.

• Gastrocnemius for ankle stability
• Gastrocnemius for knee stability (Don’t forget that the gastrocnemius not only crosses the ankle joint but the knee as well!)
• Vastus Medialis for knee stability
• Biceps Femoris for hip stability (Again, its unfortunate Gluteal activity was not recorded)

Your Thoughts?

*Here’s a video I found of squatting with pretty decent technique. The trunk and tibia are parallel, he’s in neutral spine, he doesn’t sandwich, and his weight is relatively back on his heels. Not sure about the guy doing dips in the background though!

Photo source

No related posts.

Related posts brought to you by Yet Another Related Posts Plugin.