Category Archives: Low Back Reconditioning

Finding Your Ideal Squat Depth


I’ve discussed squat depth in multiple articles over the past couple of years. I’ve talked about hip anatomy HERE, and I’ve talked about buttwink HERE. But how do you know what your ideal squat depth is?


Get down into the squat position and find the exact moment where you start to lose your lumbopelvic positioning – you need to keep the arch in your lumbar spine – no going into flexion, and keep the tilt in your pelvis – no going into posterior pelvic tilt. Make sure you stay planted on your heels and don’t rise up onto your toes. From there, you can determine if you want to go slightly deeper, but keep in mind that there’s only so much wiggle room and it may be best to play it safe. Here’s a video that better explains it:

A Simple Test for Glute Activity

Robert A. Panariello MS, PT, ATC, CSCS
Professional Physical Therapy
Professional Athletic Performance Center
New York, New York

In recent years the gluteal muscle group has received much notoriety in the physical rehabilitation, fitness, and sports performance industries. Bret Contreras is one individual who has certainly carried the “gluteal torch” on his website, in books, and lectures in an attempt to educate sports performance and fitness professionals of the significance of this muscle group. The gluteal muscle group includes the gluteus maximus (one of the most powerful muscles in the body), medius, and minimus, which together make up the buttock. There is also documentation from those who consider the small tensor fasciae latae part of this muscle group as well.

The gluteal muscles are a significant contributor to proper posture, physical esthetics, the rehabilitation of low back, hip, and knee pathology, as well as optimal athletic performance to name a few. This muscle group also contributes to the high force application into the ground surface area for favorable body propulsion, deceleration from high velocities and landings, and change of direction abilities. The gluteal muscle group also safeguards the preservation of the athlete’s posture and contributes to the appropriate vertical hip height during high velocity activities. This commentary will discuss a gluteal testing technique presented to me years ago by my good friend Hall of Fame Strength and Conditioning (S&C) Coach Al Vermeil as taught to him by renowned physical therapist Mark Comerford.

The Gluteal Muscle Group

Many dialogs regarding the gluteal muscle group may include “activation”, force production, and “function” to name a few. One aspect of athletic performance not often discussed during these conversations is the contribution of the gluteal muscles for the maintenance of proper hip height during sprinting and other high velocity athletic activities. This “vertical hip height” lesson was imparted upon me years ago by distinguished sprint coach Charlie Francis at the time Charlie, Al Vermeil and I were all hired by an NFL football team and worked together as consultants with their football players during the off-season. This lesson was also reinforced during recent sprint training discussions with Charlie’s protégé’ and my good friend S&C Coach Derek Hansen.

The gluteus maximus is known as a strong extensor of the hip, however one must not forget that the hamstring muscle group plays a dynamic role in hip extension function as well. During high velocity activities the athlete’s optimal hip height (posture) must be maintained. Weak muscles will result in a decrease in hip height thus effecting the position of the stance foot at the time of ground contact. This decrease in hip height signifies a diminished distance from the hip to the ground surface area, resulting in a foot contact further anterior to the body’s center of mass than desired. Due to this change in foot contact position some significant consequences may transpire. These changes include, but are not limited to the following:

  1. Increased ground contact times (increased amortization) resulting in less elastic energy available for force output.
  2. Decreased flight time and distance covered
  3. An greater amount of energy is required to maintain the body above the center of mass
  4. A “pawing” vs. a “punching” of the ground surface area ensues. This results in a greater “pull through” by the lower extremity to propel the body forward. This adjustment requires the hamstring muscle group to make a greater contribution as a knee flexor, thus repetitive strides over time set the table for possible hamstring injury.

A Simple Test for the Glutes

The gluteal testing procedure requires a standard treatment table with a plyobox the height of approximately 12 inches lower than the table height placed at the end of the table. The athlete lays supine at the end of the table with their knees flexed to 90 degrees. Their feet are positioned flat upon the plyobox. (Figure 1).

Figure 1. The Starting Gluteal Test Position

Figure 1. The Starting Gluteal Test Position

When instructed, the athlete performs a bilateral lower extremity bridge (raises their hips) for a specific number of prescribed repetitions and reports if they feel the muscle activity in the gluteal or hamstring muscle groups (Figure 2a). The test is repeated performing a single leg bridge with each lower extremity (Figure 2b). The athlete once again reports if the muscle activity is felt in the gluteal or the hamstring muscle groups. If the test performance is felt in the hamstring muscle group the gluteal muscles are assumed to be performing sub-optimally and require additional training.


Figure 2a. Bridging

Figure 2b. Single Leg Bridge

Figure 2b. Single Leg Bridge

The Active Insufficiency of a Muscle Group

The length-tension position of a muscle fiber will affect the ability of the muscle fiber to produce force. The gluteal test described is founded upon the principal of “active insufficiency” which based on the body positioning of this test, will have a specific effect on the hamstring muscles ability to produce force. The active insufficiency concept of a muscle transpires when a two joint (biarticular) muscle is shortened at one end while a muscle contraction is initiated at the second joint. Due to the close proximately of the muscle attachments, the muscle is placed at a low point on the length tension curve resulting in a diminished capacity to produce force. Therefore biarticular muscles placed in a position of active insufficiency will consequently produce a weaker muscle contraction.

The hamstrings are a biarticular muscle group with attachments at both the hip (pelvis) and the knee. At the initiation of testing, the hip joint is positioned in an extended position while the knees are simultaneously flexed to 90 degrees resulting in a hamstring position of active insufficiency. This shortened position the hamstrings results in a decreased ability to produce ideal tension (force), thus the emphasis of the hip extension performance is now placed upon the gluteal muscles. During the test performance if a significant exercise performance contribution were felt in the hamstring muscle group, due to the limited ability for this muscle group to produce force, the tester would conclude the gluteal muscles were not performing optimally.

This test is an effective component of the evaluation process of both the patients we rehabilitate as well as the athletes we train at our facilities. Hopefully it will be a consideration as a component of your evaluation as well.

How Does Foam Rolling Work? And Why “SMR” Should be Called “SMT”

Today, I’m going to share a discussion on Facebook that I recently had with Todd Hargrove and Greg Lehman. I’m not always confident with my understanding of things, but I’ve developed great “go-to guys” over the years when I’m seeking answers in various topics, and Todd and Greg are well-versed in areas pertaining to manual therapy.

I lift weights every day with a ton of strong dudes. Nearly all of them foam roll. I foam roll and use the stick and a lacrosse ball too. Are we all just a bunch of dumb meatheads falling prey to The Placebo Effect? Or is there more to foam rolling than meats the eye? Are we changing mechanical properties in the fascia? Or are there other mechanisms at play?

Over the past decade, strength coaches have come up with a number of potential mechanisms to explain how and why foam rolling is working. Though these theories made sense at the time, most of them are now outdated. I hope you appreciate the conversation.

foam rolling


Hey Todd and Greg, I want to write a blogpost about “How Foam Rolling Works” and pretty much repeat what Todd wrote about DNIC. I’m going to link to blogposts that you have written. But I wanted to ask you all whether or not you think there’s any merit in Schleip’s thoughts here:

And, do each of you agree that DNIC makes the most sense in regards to how foam rolling works? Thank you very much for your time, Bret


Hi Bret, I think there is some merit in Schleip’s ideas, and I discussed them briefly in my paragraph titled “4. Does Foam Rolling Work by Proprioceptive Stimulation?” My answer is that stimulation of mechanoreceptors is probably part of the story, but I think DNIC is a better explanation.

Someone pointed out in the comments to my post that Schleip has new proposed mechanism – something like squeezing water from a sponge. (See the comment by Margy) I never looked into it, but I noticed Chaitow referenced it recently in an FB post.


Thanks Todd! Greg, I would appreciate your thoughts. All of my lifting partners swear that foam rolling has made their muscles more pliable over time. I’m inclined to think that they’re full of it and that they’re just imagining things, but if Schleip’s theory is correct then it could make sense.


Two thoughts:

1. I would guess there is a transient increase in stretch tolerance and ROM after foam rolling. Your friends might then go train a little easier at end ROM and it is this new training and confidence at end ROM that ends up increasing their extensibility or comfort with new ROMs.

2. Pain reduction: I would not put this solely on DNIC. People will certainly report pain relief without having to mash the shit out of their tissues. I would guess that the pain relief mechanism is the same as every other pain relief mechanism from manual therapy or movement. Meaning we probably don’t know but its a lot of little things that deal with the resolution of our pain output. This could be all the non-specific effects we talk about: fuzzy homunculus, refreshing the sensory cortex, beliefs about treatment and satisfying an expectation, paying attention to the area etc. If someone can tell me what manual therapy does then we can probably say that that is what foam rolling does.

I certainly don’t think scar tissue or mechanical adhesions are being removed.

As for long-term changes I suppose it is possible that the tissue might change via mechanotransduction if the load is consistent and frequent over time. I don’t know why this would make some more pliable it seems just as likely to make the tissue more robust.

Sorry, no good answers there.


BTW, Chaitow recently referenced Schelip’s research on water extrusion, which I haven’t read. Here’s a good quote, which supports my idea that if foam rolling has any benefit, it is temporary, but opens up a “window of opportunity”:

“Schleip and Klingler observe temporary easing of stiffness after water is extruded from fascial tissues, returning to stiffness as it is resorbed (after 20-30 minutes)…this window of reduced stiffness offers chance for mobilization etc, but does not seem to account for sustained reduction in stiffness.”


Let’s try to form a current consensus between us:

Theories that are out are:

1. Pizoelectricity – liquid crystals spark and realign tissues

2. Thixotropy – fluid-like flow from agitation

3. Fuzz – unsolidification of loose connective tissue

4. Scar tissue and adhesion removal – breaking down scar tissue and removing adhesions

5. Trigger point therapy – releasing trigger points

6. Myofascial meridians – affecting one part of the body’s fascia impacts the whole chain

But still on the plate are:

1. Increased stretch tolerance – transient decrease in stretch-related pain sensation

2. DNIC – pain distraction

3. Placebo effect – believing makes it real

4. Refreshing the somatosensory cortex – clearing pain-related “defaults” in the brain/body

5. Proprioceptive stimulation – transient decrease in muscle tone due to mechanotransduction

6. Spongy window – dehydrating tissue followed by a subsequent rehydration, with a window of opportunity in between

Are these correct?

What else is in, or out?

Should self-myofascial release be given a new name? If so, what 3 letter acronym?


With #3. Placebo isn’t really the right word. Use it. But clarify that there are really effects behind it. Expectation and satisfying that expectation being one of them. I don’t know this stuff off the top of my head but that paper by A Louw on A neuroscience approach to low back pain in athletes would probably touch on it.

But honestly, if we solve why manual therapy works then I bet we can say why foam rolling helps with pain.


Hi Bret, those look good. Here are a few comments, each of which are pretty trivial.

First, in reference to the meridians idea, I would not disagree that causing structural changes to the fascia in one area would have mechanical effects in another area. I just disagree with the idea that foam rolling could affect the fascia.

Second, I might somehow combine numbers four and five of the second list. In other words, the effects on the somatosensory cortex are due mostly to proprioceptive stimulation.

Third, the “window of opportunity” applies to more than just the sponge. It would also apply to any other mechanisms (e.g. DNIC) which would create temporary benefits in mobility or pain reduction.

Fourth, I haven’t read anything at all about the water/sponge theory so I have no idea whether it “holds water.” Ouch!

Oh, and in regard to your question about the term “myofascial release”, I don’t like that term at all as applied to foam rolling or any manual technique. It is describing a theoretical and implausible mechanism of effect, as opposed to the actual technique.

Therefore, it’s confusing and causes people to assume that when you are foam rolling, you are releasing fascia, even though there are many other ways that foam rolling might cause changes to your movement that have nothing to do with fascia.

Calling foam rolling MFR is like calling sit ups “ab shredding.”


Awesome stuff guys! So it should be called…..wait for the drumroll…..Self Manual Therapy (SMT)?


SMT sounds great. That way, no one will be confused about what you are taking about.


If you find this interview to be interesting, here are some more links you can check out:

Paul Ingraham on trigger points

Todd Hargrove on the mechanisms of how foam rolling works (and how it doesn’t work)

Greg Lehman on fascia science

Todd Hargrove on fascia

Alice Sanvito on how we can’t stretch fascia

Paul Ingraham on fascial neurobiology

Chris Beardsley summarizing current research on foam rolling

foam rolling

5 Things You Should Do Everyday

In 1970, the average United States citizen spent $356 on healthcare. This figure rose to $8,402 by 2010.  When ranked as a percentage of GDP, healthcare costs were 7.2% in 1970 and 18% in 2010 (1). As you can see, healthcare costs have risen tremendously over the years. It is therefore in all or our financial best interests to take care of our bodies. Here are five such things that you should probably do every single day; things that will help you maintain proper functioning and prevent costly medical expenses later on in life.

Deep Squat

Why it’s a good idea:  The deep squat will help you maintain your hip flexion mobility (a technical way of saying that you’ll retain the ability to squat all the way down) throughout life. The deep squat is performed much more commonly in many Asian and Middle East countries and requires 95-130 degrees of hip flexion and 110-165 degrees of knee flexion (which is a lot of range of motion) (2,3). If you use this ability, you’ll keep it. If you don’t, however, you’ll lose it. Dr. Stuart McGill started performing this drill daily and credits it for helping him retain his hip function and prevent hip replacement surgery (4). If you’re a lifter, you want to retain your deep squat ability, as it’s been shown to lead to greater vertical jump transfer, quadricep and hamstring hypertrophy, glute activation, hip extension torque, postactivation potentiation, and deep squat strength compared to shallower squatting (5-10).

What to do: You don’t want to use extra loading on this drill, so no dumbbells, kettlebells, or barbells. Just squat all the way down as deep as you can go with your own body weight and remain flat-footed (don’t come up onto the toes). Now, with loaded squatting, it’s imperative that you prevent the lumbar spine from excessive rounding. But with the bodyweight deep squat, it’s okay to relax and let the spine sink down into the stretch. Hang out in the deep squat position for 30 seconds then rise back up. Just do this one time.  

Deep Squat

Deep Squat

Glute Squeeze

Why it’s a good idea: The majority of great strength coaches including Michael Boyle, Mark Verstegen, Eric Cressey, and Mike Robertson started noticing several years back an alarming trend – clients even athletes were showing up to the weight-room with weak and poorly activating glutes. Dr. Stu McGill even coined this phenomenon “gluteal amnesia” (11). These same strength coaches have been able to cure this “amnesia” with some basic low-load exercises. In fact, a recent study showed that prescribing isometric glute squeezes to patients who suffered from spinal cord injuries increased their usage of the glutes during gait which enabled them to walk faster (12). Your glutes are likely not functioning to their full extent, and simply performing a maximal glute contraction each day will go a long way in allowing them to retain (or even build) their neuromuscular capacity. The gluteus maximus transfers force throughout the body, compensates for other muscles when needed, and protects the SI joint, low back, knees, ACL, hamstrings, and anterior hips from pain and injury (13-23). By working on his glute function, Dr. Stu McGill was able to improve his posture, reduce hip labrum spurs, and prolong his hip replacement surgery (4). As you can see, you want to retain your glute mass and neural drive as you age.

What to do: From a standing position, take a moderate to wide stance and flare the feet out slightly. Now squeeze the glutes as hard as possible for 30 seconds. Make “fists” to increase the neural drive through irradiation. Just do this one time.

Glute Squeeze

Glute Squeeze

Hamstring Stretch

Why it’s a good idea: Stretching in general is euphoric and good for reducing anxiety and improving well-being (24). If the hamstrings are tight, it’ll negatively impact the way an individual picks objects off the ground during stoop lifting. Stretching the hamstrings will immediately improve their stoop lifting mechanics by decreasing spinal motion and increasing hip motion (25). Lifters with excessively tight hamstrings are more susceptible to deadlifting injuries. Tight hamstrings also contribute to plantar fascitiis (26-28). As you can see, you don’t want your hamstrings getting tight over the years.  

What to do: 

There are many good hamstring stretches, including ones that can be performed in the standing, supine, and seated position, so just pick one that you’re most comfortable performing. Hold the stretch for 30 seconds on each side.

Hamstring Stretch

Hamstring Stretch

Crucifix Stretch

Why it’s a good idea: Our society has become increasingly sedentary over the years, and this sedentarism is not so good for low back pain and function (29). And all the prolonged sitting we do is generally not very good for back pain either (30-31). The typical desk-worker is slumped over with a rounded spine and rounded shoulders, along with a forward head position. We want to “undo” this posture by stretching the shortened muscles and strengthening the lengthened muscles. Rest assured, the crucifix stretch achieves both of these criteria.

What to do: 

Stand tall and place the arms out to the sides. Simultaneously extend the spine by picking the chest up and externally rotating the shoulders by pointing the thumbs behind you. Keep the head and neck in a neutral or packed position (which resembles a double-chin). Hold this position for 3 seconds and repeat 5-10 times.

Crucifix Stretch

Crucifix Stretch

Diaphragmatic Breathing

Why it’s a good idea:  People these days are too stressed out! Increasing responsibilities and pressure takes its toll by negatively impacting our neuroendocrine, metabolic, and immune systems (32). This stress impacts the way we breathe. In fact, upper chest breathers exhibit poor cardiovascular efficiency and nervous system balance (33). The good news is that breathing retraining is very effective, and by practicing various breathing techniques, you can reduce anxiety, reduce oxidative stress, improve quality of life, achieve better balance of the parasympathetic and sympathetic divisions of the autonomic nervous systems, reduce blood pressure, and reduce resting heart rate (34-41). In short, it’s well worth it to spend a few minutes per day on specialized breathing techniques.

What to do: There are many effective breathing methods that you can experiment with. Here’s one that I really like. Lay down and place one hand on your chest and one hand on your belly. Relax all of your muscles and begin breathing deep. Pull air into your belly first and then into your chest. If you do it correctly, you’ll feel the hand on your belly rise for the first two-thirds of the breath, then the hand on your chest will rise for the last-third of the breath. Make sure your exhalation lasts longer than your inhalation; ideally around twice as long. Do this for 3-5 minutes.

Diaphragmatic Breathing

Diaphragmatic Breathing

These five activities will only take up 6-8 minutes of your day but will likely do wonders in terms of longevity and well-being in later years of life. Take care of your body and do the small things that count!


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