PT on the Net Research

Isolation to Integration Training? Part 1

In our continual attempt to understand the complex human body to a greater degree, our attention has focused more and more on the specifics that make up the body. We can all appreciate our first experiences learning about each muscle of the body. I remember trying to study each individual muscle, where it was located (i.e., what bone it was attached to) and how it functioned to move the bones in its isolated ways. I learned that the Pectoralis Major muscle attached from the lateral lip of the bicipital groove of the humerus to its clavicular and sternal attachments. Its isolated role, as a result, would be horizontal adduction and internal rotation of the humerus. Years of anatomical studies has delineated our current muscular model of the body. Most of this looks at the isolated function of muscles. Muscle testing during the Polio epidemic of the 1950s laid the framework for how we understand muscle’s function. Areas of the body were isolated by having people lie down in unusual and unnatural positions to "test" isolated functions of an individual muscle. The goal was to separate the body into its individual parts. Program design and training then shifted focus to training the individual muscles of the body. The thought process at the time was that if systems were trained and strengthened in isolation, then the building blocks would be set to assemble a strong, stable body. Research followed suit by testing, observing and modeling the body in "isolation."

Studies have been performed to "assess" core stabilization. An individual is asked to lie supine on his back with his pelvis fixed on the ground. A "natural" lordotic curve is then preset (many times using a blood pressure cuff). The subject is then asked to slowly lower the leg at the hip, and a neutral spine (i.e., one that does not move) must be present for a "successful" test (see Figure 1 below).

Figure 1. Supine Leg Lowering Test

In Figure 1 above, the subject raises the leg (as shown) and then attempts to lower the leg at the hip without moving anything else. If the lumbar segments of the spine move, then this is judged as poor core stability.

In recent studies using this protocol, all subjects (healthy or unhealthy, athletic or sedentary) were seen to exhibit lumbar movement as soon as the hip joint was in motion.

Could every subject in the above study have been "dysfunctional??" Does this mean that everyone’s core is not functioning correctly?? Or is the body doing this for a reason?

In looking at the biomechanics of human gait, does it seem likely that the body would move its hip joint without a corresponding reaction (movement) at the pelvis and lumbar spine? For that matter, wouldn’t the body rather move from EVERY link to attenuate forces correctly?

This is exactly what researchers have concluded: the hip joint cannot effectively move without the pelvis and spine also moving. The question is how much movement should we get at each link? There is no question that the amount of physiological motion that can be derived from the hip complex far exceeds that of the lumbar segments. The point of this article, however, is to show that there are underlining relationships that exist between the body’s segments. And these relationships must be preserved and trained if our bodies are to work effectively and efficiently.

As our understanding begins to grow, there are now questions as to the validity of conventional models. How can forces be dissipated over the body so well if our muscles work as isolated entities? Why are all of the other systems of our bodies so integrated? What about the muscular system? As we are about to find out, the myofascial system (muscles and fascia) is just as integrated as any other system of the body!

Figure 2. Deltoids

In Figure 2 above, notice how there is a continuation of muscle that extends out from the deltoids. There is a prominent fan shape from the deltoids to the pectoralis major. There is also a linear flow of muscle: from the deltoids down the arm and a very apparent line of muscle from the deltoids up on the superior side of the clavicle (the trapezius).

In observing the cardiovascular system or the nervous system, we clearly see the integrated nature of these systems (see Figures 3 and 4). Every link of the cardio system has a need to work with every other link. Think of how vital it is that the vessels leaving the heart (from the aortic arch onward) link with its corresponding vessels. These networks form a crucial union. It is the relationships of the cardiovascular system that allow it to exist (see Figure 3 below).

Figure 3. The Cardiovascular System

It clearly works as one system. If we were to remove all tissue of the human body and leave simply the CV system, it would still look like the human body! It is a unifying system.

Our complex nervous system is no different. Of our one trillion nerves that exist within us, there is a link between each of them (see Figure 4 below). If we were able to remove all of the nervous tissue from our bodies and place them end to end, it would extend long enough to travel around the world twice! Now that’s integrated!!

Figure 4. The Nervous System

There is a need for the nervous system to work in integration. The more skilled a human movement is, the more there is an interaction between the afferent and efferent divisions of the nervous system.

Why then has our understanding of the myofascial system (muscular system) been limited to simply seeing muscles as individual entities? How can such a ubiquitous system work in isolation? The quick answer is that it cannot!

Anatomists of late have given a greater conceptual model of muscles in integration. Looking at the lat and the contra-lateral glute, for example, we see a connection or a union between these two muscles (see Figure 5 below).

Figure 5. The Human Muscular System

Notice the myofascial line between the latissimus dorsi (1) and contra-lateral gluteus maximus (3) (denoted by the solid black line). It is becoming clear that to effectively work one of these muscles, both have to contract to effectively stabilize the sacro-iliac (SI) joints and approximate the pelvis (bring both sides of the pelvis closer together).

The latissimus dorsi (1) and gluteus maximus (3) are linked through the throaco-lumbar fascia (2) (they both attach to the superficial lamina on the posterior layer of the fascia – in other words, they are a continuation of the same muscle). To truly create a stable line of force through the SI joints, the lat and opposite glute muscle must contract together. If this does not occur, we lose the effectiveness of our myofascial system. Before isolating the lat and the glute to "strengthen" them, we must FIRST teach the body strength in this sling SYSTEM (in other words, we must train them together). Figure 6 is an excellent exercise to prepare the body for stable mobility. Consider doing this exercise BEFORE an isolated strength movement.  

Figure 6. 1 Leg Squat w/Bungee Row

This exercise should be performed without a bungee with the trail leg toed down in a staggered manner for beginners.

Think of the old paradigm of working muscles in isolation before integration. We would train either the lat or glute to be effective on its own. We would ask one of these muscles to contract themselves, all the while destabilizing our lower back and decreasing our ability to function properly. There are plenty of muscle "sling" examples in the body. In fact, it is impossible for us to look at muscle attachments and not see unions everywhere we look. (For a thorough read, I would highly recommend Thomas Myers' book Anatomy Trains.)

Another point that must be addressed is the research by Zajac & Gordon, Andrews and Basmajian. Their work, which spans more than a decade, involves looking at the "functional" role of muscles. Interesting to note is their conclusions that a muscle does not need to cross a joint to bring about acceleration of that joint. In other words, muscles have far reaching effects because all muscles operate together if given the choice. For example, the soleus muscle, which does not cross the knee joint, will “accelerated the knee joint into extension twice and much as it acts on the ankle in positions near upright.” Simply put, it is one of our main knee extensors, and IT DOES NOT EVEN CROSS THE KNEE. The soleus would prefer to work with the muscles of the thigh than on its own. This is interesting for the simple fact that if we tried to isolate the soleus before integrating it, we would lose its main function in upright positions! This is only one example of our bodies work in life.

The next step for anatomists is to start putting together the relationships between muscles that, to this point, have been broken down and separated. A lot more work needs to be done in this area of anatomy. However, researchers, biomechanists and anatomists are doing a great job in furthering our understanding of the roles of muscle in integration. Clinical models and research is starting to speak more and more to the integrative nature of the muscular system. It is the job of the fitness industry to follow suit and start to create bodies that can move well TOGETHER. Moreover, this creates ancillary health benefits such as improved circulation (via a body wide muscle pump), increased nervous system stimulation and better force attenuation. For more examples of integrated exercises, please refer to PTontheNet’s Exercise & Flexibility Library (search Muscle Group -> Total Body). Please note that the exercises should be given without load of any kind before progressing to load (i.e., dumbbell, barbell, bungee, medicine ball, etc).

In part 2 of this series, we will explore the value of designing a program using integration training and also explore an architectural and mathematical model explaining how the human body dissipates forces in integration.

Have fun in training!!


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