Following are drawings to provide a perspective of this anatomical complexity.

From this expansive list of structures and pictures, it is obvious that there are many muscles involved in scapular movement. Unfortunately, many of us lead modern lifestyles that can lead to disuse of these muscles, and this can result in debilitating weakness and pain. This problem is exacerbated by the fact that these structures are easily ignored in exercise programs (even strength exercise programs and therapy treatments), because they are difficult to access by conventional exercises.

There is also the infamous Rotator Cuff: a group of four muscles that run from the scapula to the humerus of the upper arm. These specific structures are key shoulder girdle stabilizers. Once again, however, because of their small size and rather invisible nesting, these muscles can become damaged insidiously, after years of disuse atrophy. If any of these shoulder girdle structures break or tear, the result is a marked inability to move the arm freely.

But the trouble doesn’t end with the scapular structures. The Rowing Torso exercise also indirectly involves some of the structures of the spine, most notably the cervical (neck) muscles. These structures, both intrinsic and extrinsic, are inextricably linked to the latticework of the numerous scapular muscles. Weakness in one muscle system can create a prolific chain reaction that affects practically the entire upper middle back area—from the base of the skull all the way down to the gates of the lower spine. In fact, the Rowing Torso can influence muscles that span all three spinal segments.

Given the importance of the payload that they support, it’s ironic that so many of the scapular structures can deteriorate to such progressive fragility over time. Without the necessary strength in these various muscles, it’s no wonder that so many people suffer from weakness, pain, debility, and stress.

The Posture Machine Revisited: The All-New RenEx Simple Row

In his textbook, Ken Hutchins likens the shoulder more appropriately to a suspension rather than a proper joint, one that depends squarely on the strength of all of its constituent muscles to keep the appropriate balance of tension between the associated structures. He also warns about the dangers of dynamic use of rotary-form machines for the shoulder, most notably arm cross, lateral raise, and pullover machines.

However, despite its status as a direct shoulder machine, the Rowing Torso has earned a special dispensation because of its unique ability to provide shoulder security and a sensible movement path for the arms and shoulders. The anchoring effect of the chest pad ensures reliably stable horizontal shoulder abduction. Because of this, the Rowing Torso is not only uniquely exempted from the safety concerns common to the other direct shoulder machines, but it is also credited as being an important tool in the treatment of many debilities not addressed by other exercises.

It was important to the Renaissance Exercise team that we revisit and rework this special machine with the same verve and passion that we brought to the development of all the other machines in the RenEx equipment lineup.

The RenEx Simple Row(sRow) represents the evolution of exercise for the scapular muscles first established with the Nautilus Rowing Torso. Although not immediately evident, the Rowing Torso is technically the rotary-form parallel of the Compound Row machine. We distinguish between linear, multi-joint, or compound machines and rotary-form, single joint or simple machines, hence our new moniker “Simple Row.”

We began our re-dux by addressing the primary shortcomings of the stalwart original. In particular we were interested in improving three key aspects:

• Entry/exit
• Hand positioning
• Resistance profile

Since entry and exit are always a concern from an operational perspective in any studio, it was imperative to confront this as the first challenge.

Getting in and out of the Nautilus machine had always been a significant drawback of the original machine, especially for frail and/or obese subjects. To make matters worse, many subjects experienced a kind of anxiety over the claustrophobic nature of the positioning once in the machine. In essence, once properly seated, a subject was rather “jailed” in the machine with an immovable chest pad and the movement arms in front and a back pad and weight stack behind. Of course, over time, such concerns could be overcome, but the initial challenge was always there.

The RenEx machine solves the entry-and-exit problem by reversing the subject and the movement arms to face the weight stack. (Note that the early Nautilus models provided this same relationship, but still boxed in the subject.) This design completely liberates the rear of the machine thus enabling total freedom for entry and exit. It also facilitates straightforward adjustment of the chest pad to establish coaxial alignment of the shoulders. Additionally, height adjustment is managed easily with the use of an auxiliary seat pad, if needed. And with the entire rear of the machine unobstructed, an instructor can better observe the nuances of any subject’s performance.

Our second challenge was the positioning of the hands and the orientation of the shoulder. The traditional protocol on the Rowing Torso (denoted Subprotocol #1) mandated maintaining an internally rotated shoulder with the arms crossed over each. Later, an externally rotated shoulder was also possible (denoted Subprotocol #2), most recently with the provision of handles at the tops of the roller pads.

While the handles proved to be a worthwhile addition to the machine and helped to solve the challenges some subjects had with certain frailties, the angle of the handles seemed to conflict with the ideal maintenance of the externally rotated shoulder. The SuperSlow Systems handles on the Rowing Torso required a less-supinated grip. Upon careful observation, this grip actually interfered somewhat with the subject’s ability to maintain the proper forearm attitude in the movement arms and engage in all the behaviors necessary to protect the shoulders and the neck.

The Simple Row, by contrast, features parallel and in-line sets of handles that place the hands in a more-completely supinated position. This is a more natural and effective hand positioning that is easier to maintain throughout the set. It is also far more comfortable. Two sets of handles—an upper and a lower set—ensure that various subjects’ arm lengths can all be accommodated.

Topping off this subtle but important refinement are the adjustable movement arms. With a simple pop-pin adjustment the movement arms can be moved to virtually any position in five-degree increments and accommodate a wide range of shoulder concerns.

Our final challenge was the resistance curve. In part, Ken had solved this challenge when he developed the retrofit kit for the Rowing Torso and later for the SuperSlow Systems Re-engineered Rowing Torso. This new cam was nearly perfect for the action of horizontal abduction. However, there were always select subjects for whom the resistance curve was insufficient.

Like the Compound Row and various other machines in the RenEx Equipment lineup, The RenEx Simple Row is furnished with a resistance-modulating cam that can be timed to match any subject’s specific range of motion. Such capabilities mean significantly greater control for the instructor and a much more personal experience for the end-user.

Compound Counterpart: A Scapular One-Two Punch

One of the most productive and potent experiences in strengthening exercise is the pre-exhaust superset. In a pre-exhaust combination, an exercise for a particular structure is first performed on a rotary-form (or simple) machine. With practically zero rest after the completion of the first exercise, a secondary exercise is performed for the same muscular structure but this time on a linear (or compound) machine. The second exercise in the dyad involves more joints and more muscles, which then pilot the already worked primary structures to yet harder work and deeper fatigue. The result of the combined exercises represents a one-two punch, whereby the worked structures have experienced an exponential rather than just an additive effect.

Of all of the pre-exhaust combinations that are available, the integrated effect of performing Simple Row PLUS Compound Row is perhaps the most formidable and exhilarating of all. When this pre-exhaustion series is successfully followed by another combination of static lateral raise PLUS Overhead Press, the result is a peerless stimulation of the shoulder and torso structures.

From this general framework, additional exercises can precede or follow including internal/external shoulder rotation, cervical exercises, or even trunk exercises.

Conclusion

The key traits responsible for the success of the Re-engineered Rowing Torso are all present in the new RenEx Simple Row, including a notably small footprint and fused movement arms, but they have been painstakingly refined.

A lighter (15-lb) aluminum top plate and 1.25-lb weight increments assure that even the most debilitated subjects can get started on a program of progressive rehabilitation while the rigid frame, dual handles, generous arm pads, and ample weight stack guarantee that even the largest, most muscular athlete can intensely stimulate the upper back musculature.

The Simple Row’s range delimiter features stops in five-degree increments for true precision in tailoring the user’s endpoint. An optional load cell at the endpoint stop assures accurate load-sensing technology is always available to measure squeeze technique effort as well as providing the foundation for reliable, independent timed-static-contraction exercise at various positions in the range of motion.

As with all the RenEx Equipment, the Simple Row machine features all the successful elements of our resistance delivery system including the Freedom Stack™ and the UltraGlide™ top plate system, which delivers resistance in fluid, anti-friction style. Regardless of how much or how little resistance you select, rep after rep, set after set, the weight stack will behave with remarkably predictable, zero-contact precision for a truly inimitable strength training experience.

Whether you plan to use it for pure strength exercise, facilitate delicate rehabilitation for the rotator cuff, help improve posture, or relieve tension, the Simple Row is among the essential tools in the RenEx arsenal providing many clients with a true scapular solution.

If you are interested in adding the RenEx Simple Row to your line of equipment so you can personally, along with your clients,  reap the numerous results this piece produces please contact us at info@ren-ex.com or call the office at 216-292-7569.

P.S. The Simple Row was unveiled to the public for the first time at The Future of Exercise Event.  If you haven’t grabbed your copy of The Future of Exercise DVDs don’t miss out! CLICK HERE!

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Exercise for the Human Knee
Part II

by Ken Hutchins

 Note: This material is excerpted from a more-complete chapter in
The Renaissance of Exercise – Volume II by Ken Hutchins.

Potentially, as we noted in Part I, the best overall exercise is a leg press. A leg press is a compound movement or multiple-joint movement or linear movement. All of these terms mean much the same thing. And the physical therapists introduced a fourth term several decades ago—closed-chain.

And potentially, the most geometrically perfect exercise is a knee extension. A knee extension is a simple movement or single-joint movement or rotary-form movement. The term now used by the supposedly enlightened is open-chain.

When referring to simple movements, I am particularly toward the usage of “rotary-form.” Note that I do not use “rotary movement” or “rotational movement.” These terms might suffice, but I avoid them because of distinctions I noticed during 1983-1985. Since then only “rotary form” rings true to my ears. I will try to explain. Perhaps I can justify my linguistic bias.

Arthur liked the term, “rotary resistance.” As I alluded in Part I and in other writings, “rotary resistance” is part of Arthur’s dupery. In physics, there is no such thing.

Of course, we have torque, which is a product of force magnitude and lever length. I can only excuse Arthur’s technical imprecision with “rotary resistance,” since he was trying to communicate with morons who can never understand torque. Nevertheless, he misled thousands of people with his bastardization of physics.

Rotary Resistance was the first and most important requirement in Arthur’s faulty Ten Requirements of Full-Range Exercise. Any rotary-form exercise might qualify as full-range, but no compound movement was eligible, first of all, because it was linear-form.

So… rotary resistance is a non-starter. And the terms, rotary movement and rotational movement (also rotatory movement) imply that movement—although perhaps desirable— is necessary for exercise and it is not.

Rotary-form (or rotational format, with additional and unnecessary syllables) says more about the nature of the joint—whether is it is moving or static. Hence, I stick with this term.

Another distinction: In Arthur’s words, the Nautilus Pullover “provides rotary resistance.” In addition to my criticisms of “rotary resistance,” I also focus on “provides.” Whether Arthur knew it or not—and I’m certain he did not—“provides” was a limiting factor of the device.

The Nautilus Pullover did not cause, impose, require, make, produce, or create a resistance on a rotational format. The joint—axle—of the machine forces the machine to rotate on its singular movement-arm axis, but it does not force the subject’s arms to rotate on the machine’s axes.

The rotational behavior of the subject’s upper arm(s) was caused by the joint itself. Due to its internal geometry as well as the ligaments, capsule, and muscular systems about it, the joint requires rotation to occur if movement is to occur. No external device did this, regardless of the nature of the device—at least not until the advent of the coupled movement arm. And the coupled movement arm was never incorporated into the Pullover.

I will explain the coupled movement arm and its effect on a joint later in Part IV, but first we must appreciate the reactionary forces of the more-common, non-coupled movement arm.

Note the following photographic series of a prototype Nautilus Pullover. This machine was the first of its kind to place the workbox and weight stack on one side of the machine. I believe that this machine was the basis for the Series III Nautilus equipment line.

Also note that this prototype fit women much better to their shoulder and upper arm dimensions than the production Women’s Pullover. I measured all of the various versions of Pullover back then and no one seemed concerned about this.

Although when in practical use, the right side of its axle required support, we removed this part of the frame so that observation of the body was less obstructed. In this way Brenda Hutchins and I performed this photographic analysis in 1984.

For convenience of discussion, denote instant actionary force as the force produced on the elbow pads by the subject (subject force) and denote instant reactionary force as the force pushing directly on the elbows by the machine (machine force). Instant indirect reactionary force is the force generated by the machine across a fulcrum that changes its effective direction. Instant indicates that the force occurs in this direction in only this position of the shoulders and machine.

Note that the subject is challenged throughout the pullover motion to control continually changing reactionary force. In some ways and in some exercises we might deem this as a good attribute, but it can lead to problems.

Now apply this appreciation of changing reactionary force in the Pullover to a prone knee flexion exercise.

As we approached the 1980s, the above photographic analysis had not been performed. I never heard Arthur or anyone around him explain these details. They seemed important to me. No one else seemed to care. But to a certain degree, some appreciation had to be present. After all, there were, indeed, seat belts on the Nautilus Pullover and handles on the Nautilus Leg Curl.

The same reactionary-force analysis can and should be performed upon all the other rotary-form exercise approaches—be they Nautilus, devices from other exercise equipment companies or merely manually applied.

Nevertheless, I was then to be jointed into a much deeper understanding of joint mechanics during exercise—especially exercise for the knee. And this vista of new information would not arise from a sophisticated source, but from some low brows stretching to create science from crap.

I credit (or rather discredit) Frank Noyes, MD as the progenitor of the misinformation regarding shear forces about the knee. I’m confident about this, but not 100%. If I am incorrect in my blame, I apologize to Noyes and his team, however, I have written about this for many years and have not heard a peep of correction or retraction or debate.

Shear Forces

Bad Influences From Research In the 1980s the new enlightenment regarding knee rehab was all the rage about so-called shear forces.

https://www.ren-ex.com/wp-content/uploads/2010/11/Shear-Forces-or-Sheer-Nonsense.pdf

 Would-be experts talked as though this is something special and dangerous and something to be avoided. They made a big deal about it especially as it regards the knee and especially the cruciate ligaments of the knee. And this culminated in a blanket condemnation of the knee extension exercise. This was all smartly reasoned by people who were probably immersed in highly ballistic isokinetics philosophy (“measuring forces at normal training speeds’), who gathered data from a dead human limb that was incapable of representing the dynamic synergism of a live limb.

This farcical research model was then exploded to stratospheric comedic heights by people who did not know how to properly design, build, or apply and use a knee extension machine.

Shear forces are indeed a reality, and they are ubiquitous. And they do not present special concerns for the knee in most normal and rehabilitative situations.

Also, there have been in vivo studies since the 1980s:

http://www.udel.edu/PT/PT%20Clinical%20Services/journalclub/sojc/08-09/Nov08/ACL_Open%20vs%5B1%5D.%20Closed%20Chain_Fleming_2005.pdf

Some of these seem to dismiss or minimize concern that shear is more meaningful with knee extension than with compound movement. I believe that—regardless of the interpretations—much has been overlooked.

Also, such studies almost always present hedged conclusions. If a rock-solid conclusion regarding a topic was, indeed, ever appropriate, making such a bold statement seemingly closes the door for more grant money for more research. Nevertheless, research on a live limb does not necessarily demonstrate reality when the musculatures are artificially and selectively stimulated.

Multiple Overlooked Concerns I am one of the few people who is aware of the exact resistance curves portrayed by the knee extension equipment that was provided by Nautilus, Cybex, and MedX in the past 30 years. And—regardless of these curves—I know that almost everyone else so armed with this information during those years was (and still is) extremely insensitive to the several other requirements—most importantly, movement speed—to effect a reasonably safe and productive exercise stimulus. These several other requirements include an awareness and provision for muscular sufficiency, a correct resistance curve, a minimization of friction, the containment of reactionary forces, and the application of a detailed protocol for transitioning from the positive excursion to the negative and then back again. I demand all of these requirements, though I am certain they are overlooked or unappreciated or dismissed by the usual suspects.

Is not it interesting, if not ironic, that some of the same voices that are insensitive to the these requirements of proper knee extension exercise design and application are also the same voices that criticize that I am too detailed and careful, although they condemn the performance of loaded knee extension? Sorry, it can’t be both ways.

Back to the Physics As already mentioned several times, there are only two basic kinds of movement in the universe—translation and rotation. And it is exceedingly rare to not have a mixture of these formats in any movement. Movement often incorporates a preponderance of one format over the other, but both are often present. Only in the convenience of conversational or discursive prose can we pretend or presume that one is present to the absolute exclusion of the other.

In a sense, all forces about a limb have a shear component.

As in a pullover exercise, imagine shoulder extension being produced by the latissimus dorsi. As the muscle contracts, thereby pulling the humerus inferiorly, why is there rotation at the shoulder joint?… Because the joint ligaments and capsule prevent inferior translation of the proximal end of the humerus. Thus inferior shear is arrested by superior shear containment forces or shear control of the ligaments, capsule, synovial lubricity, etc.

As regards a joint—and without getting into arcane engineering discussion—shear is nothing more than the translational movement of a body part that we wish to instead stay in place and rotate. And shear force is any force tending towards this undesirable behavior. In short, shear is undesirable translation. At least, this is the case in this application.

Sometimes the shear controls—ligaments, capsule, etc.—are external. This is what we observe with the shoulder for the most part.

And sometimes the shear controls are internal. A great example of internal shear controls is the cruciate ligaments of the human knee.

Imagine the flaps on a model airplane. They are often attached by crisscrossed strips of woven fabric. This arrangement effects a hinge. In a sense, this is what the cruciate ligaments do on the inside of the human knee.

Closed-Chain vs. Open-Chain Movement

Closed-Chain Movement such as the Leg Press gained popularity simultaneously with the underserved hysteria that emerged in the 1980s regarding shear forces.

Closed-Chain refers to the concurrent contraction performed in a leg press by the knee flexors (hamstrings) and the knee extensors (quadriceps). The reasoning—not completely  incorrect—is that the combination of forces from both musculatures during knee extension as performed on leg press is more balanced and protective to the cruciates than when performing a knee extension exercise.

[Note: Commonly used also is Closed (or Open) Kinetic Chain or CKC (or OKC). This is verbose and misleading. It implies that an isometric (or static) condition is absent from this consideration.]

A knee extension exercise is characterized as being open-chain, because the hamstrings are believed to be unloaded and non-contributive. The complete loop from the ischium through the hamstrings, to the hamstrings insertions on the tibia and fibula, through those two bones and their ligamentous attachments, to and though the patellar tendon, through the patella, through the quadriceps tendon, through the quadriceps (especially the rectus femoris), to the iliac crest, and back through the pelvis to the ischium again is said to be open.

Therefore, as the story goes, it is further reasoned that the knee receives contractile force from the quadriceps alone and that the exclusion of the hamstrings counterforce greatly threatens the cruciate ligaments and thus knee stability.

This fear of the supposed shear forces inherent in a knee extension exercise was greatly overstated, but is widely accepted today. For instance, I recently read a prescription from a physical medicine specialist stating the need for “closed-chain exercises.” And this provision is sometimes stated for the elbow and other joints as well although the elbow does not function near as loosely as the knee. The antagonist of either agonist provides little stability to the elbow when compared to the knee. What is of questionable concern for the knee is far more remotely a concern for the elbow.

I explained all the anti-knee-extension slant to Arthur for the first time in the early 80s. His reaction after stunned silence was, “Are we just not supposed to straighten and bend the knees?”

The promotion of closed-chain exercise—particularly for the knee—appears correct in theory, but it doesn’t pan out with a viable human knee in almost all cases. Nevertheless, good judgment is required and good judgment is impossible without clarifying information that is not widely available to the medical community.

First: What Are the Comparative Forces? In various situations, it may well be that the shear talkers are correct to be concerned with compromised cruciates, especially those that have been surgically repaired or replaced by such procedures as Slocum, etc. But where is the line? How do we know that force magnitude on the cruciates and its source and situational conditions effecting it? We don’t. And this was certainly not quantified with dead limbs and begs too many other questions with artificially stimulated live ones. This is asinine.

Second: The Hamstrings Are Never Completely A.W.O.L. And the assumption that the hamstrings ineffectively contain shear during a knee extension exercise is questionable from another perspective. As the knee progressively extends, the hamstrings are progressively lengthened, thus growing closer to passive insuffiency (depending on hip flexion angle). And then, if the subject sits on the hamstrings during active extension, this counterforce looms greater.

Note that, in practice at RenEx, we procedurally comb down the flesh on the posterior-distal thigh before sitting firmly for knee extension exercise. We do this to avoid the annoying tension and hair pulling that occurs as this material is stretched as the knees straighten. Although, this procedure is superficial and has little-to-no effect on the hamstrings, it does raise our attention to the fact that the hamstrings impart parallelogram force to its insertions as this contact area is squeezed due to the subject’s weight and counterforce from the movement arm. Although they are indeed unloaded, the hamstrings still render force to the knee.

Third: What About Knee Setting?? There is a huge inconsistency here. Do we not see so-called knee setting exercise ordered and performed immediately after surgery?… In bed before ambulation?… Perhaps in the recovery room? Is this not SOP for cruciate repairs and most other knee surgery except for some patellar fractures or quadriceps/patellar tendon repairs?

And this knee setting is exactly what the anti-leg extension shear talkers are condemning, except in this case it is exactly when the cruciate repair is most vulnerable. And who knows the force exerted by the patient or his relative effort? Does the patient inadvertently extend the knee harder with the quadriceps because he can’t flex his hip with part of the same muscle? This is too complex to precisely control.

I do reserve that this might be contraindicated after cruciate repair, but if it is not, we are observing widespread practice early post-operatively of exactly what the shear talkers warned about with a knee extension exercise.

Specialists also inform me that knee setting is not concerning as one might think since the repairs are now so very secure. So why would performing a knee extension exercise, per se, still cause concern? After all, the forces—a la shifted transposition—are far more controllable in a properly designed knee extension machine than with knee setting.

Fourth: Resistance Curves And there are other forces to consider. Arthur Jones noted that to truly analyze the danger to the body we must know the exact force magnitude required to cause damage—exceeding the structural integrity of the body—as well as the exact force magnitude encountered by the body. If the latter exceeds the first, then damage occurs. And we rarely, if ever, know either of these two factors in any event.

One source of force that is, indeed, knowable is the load levered on the leg from the exercise machine—the knee extension machine specifically. In general, this is not known by a knee specialist or anyone else for that matter.

In Part III, I will present a collection of resistance curves. These curves are used to identify the most offending loads provided by various equipment designs during the last 30 degrees of knee extension. These are contrasted against the ideal as displayed by the original SuperSlow^® Systems machines as well as the new RenEx curve.

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