Arthur’s Misadventures with Acceleration on the Human Knee
By Joshua Trentine
November 5, 2012
Arthur’s Misadventures with Acceleration on the Human Knee was pulled from our archives because someone in cyber world suggested that the RenEx team wasn’t up to speed on the biomechanics of the knee, what muscle and joint function meant, and the considerations that determine exercise equipment design. These challenges stem from ignorance as Ken Hutchins has written extensively on the knee, which you can read about in the article, Shear Forces or Sheer Nonsense, and in his articles on equipment design principles.
I was fortunate enough to come across Ken’s articles on this subject in the 90s when I was still working in orthopedic outpatient rehabilitation. His writing molded much of what I did in that practice, and of course, what I do now with Overload Fitness and RenEx.
Today, thousands of people have benefited from Ken’s writing on this subject and the use of his protocol for knee rehabilitation. I have had many clients come in for pre-habilitation who subsequently cancelled their knee replacement surgery due to the successful results of Ken’s protocol.
Personally, I have benefited immensely. I had a knee reconstructed in 1990 after a catastrophic injury while playing college football. Beyond a shadow of a doubt, I would not be able to do what I can do today without Ken’s machines and protocol.
Another really cool thing is our stream of breakthroughs that further enhance our ability to rehabilitate the knee. Some of these include: “The knee lubrication protocol,” the i-Leg Curl, the i-Leg Extension, and the improvements seen in the RenEx Leg Press—most notably the feedback system that optimizes TSC Leg Press… and more. With these options and a strategic organization of the exercise sequence, I believe that we can handle any knee condition and rehabilitate it to its full potential.
Getting back on subject: I do consider the DuoSquat to be one of the most interesting pieces Nautilus ever made. I’ve learned from it, and it may provide better muscular stimulation than the Barbell Squat for some, and certainly better than most commercial Leg Press and Hack Squat apparatus; however, this machine comes with a catastrophic consequence if the subject makes the slightest error with movement or recruitment.
Furthermore, the DuoSquat encourages behavioral issues, as its type of loading remains completely unnecessary for us to achieve the desirables of exercise, minus the risk. Remember: Equipment can dictate the protocol or expression of that protocol to a great extent!
The DuoSquat was designed to replace the barbell squat. In some ways it was an improvement as it allowed better range, less discomfort (compressive on the spine and at the knees), and it removed some of the risks of getting trapped under a heavy barbell.
My knock against the DuoSquat is that though there are fewer potential risks, the one that does exist may be even more catastrophic than the worst of the barbell squat injuries—and for what purpose, to what end?!
The barbell squat can be performed in a relatively safer manner when using SuperSlow protocol.
Beyond this, I intend to demonstrate that all of this harsh mechanical loading—via the negative cam in the DuoSquat,—only takes us further from the ideal; it’s counterproductive and completely unnecessary.
I remind everyone that though my rant is directed toward the DuoSquat, I believe the far more offensive dumpers (focused on harsh mechanical loading) only create more risk, more faulty recruitment patterns, and provide feedback that elicit the wrong behaviors.
We do not need 40% more on the negative. We don’t need 1,174 lbs at “lockout.” We don’t need motors dragging us through the workout. And we don’t need technology that provides less than a significant advantage over the barbell.
What we do need is apparatus that gets out of our way. The barbell and our bodyweight can be reasonably effective for these purposes and with much less risk and more reward than some of these revved-up, super-charged “solutions.”
Additionally and extremely important: you must participate intellectually in the exercise. No amount of technology of any kind will make this optional.
By the way, we are developing products to help instruct how to get more from conventional equipment.
About a week ago, Ken and I were discussing re-releasing his article Arthur’s Misadventures with Acceleration on the Human Knee. I reminded him that I still have the chrome DuoSquat in storage. We agreed that it might be interesting to pull this machine out for photos and demonstrate its intended use.
You can see from the video that what started out as a casual demonstration evolved into a strength feat. I did a few “feeler sets,” working my way up in 100-lb increments.
After four sets I found myself with the entire stack of 510 lbs. I performed a few reps and stopped, as it felt pretty easy.
With a long loading pin, I hung an extra 45 lbs from the weight stack. This brought the total up to 555 lbs. And with the negative cam and my leg nearly straight the load was something closer to 1,300 lbs.
I was able to perform 12 reps with each leg, and I performed these well shy of momentary muscular failure. I suppose if Arthur Jones was standing by with pistol in hand I could have managed 20 reps with each leg. I backed off as I realize there is far too much risk of sacroiliac injury as fatigue settles into a mechanics change.
I’m posting this video for several reasons:
1) To compare and contrast behavior and mechanics between what was recommend at Nautilus and what we do now.
2) To demonstrate that once you learn to communicate with the muscle you can access this to demonstrate superhuman capabilities in an activity in which you are skilled? or in one that requires little skill.
3) To impress upon you that you don’t need negative cams, hyper-loading machines or motors trying to trash-compact you to actualize your strength potential. They can even be counterproductive.
4) There must be meaningful load, but placing excessive forces on your body is neither necessary nor desirable.
In this demonstration I was exposed to loads of nearly 1,300 lbs, and it still “felt” easy. I normally work on our Leg Press with 420 to 500 lbs (depending where it falls in the workout), using no cam, incorporating a large weight-stack travel (stroke), and with my legs never nearing straight (15-20-degree knee flexion at the upper turnaround. Experientially, it’s a million times harder and seemingly far more productive.
Did I mention the safety factor?
For a moment, let’s suppose that the negative cam and the dumpers are required. Let’s pretend that we are trying to expose the body to the highest-possible loads. If this is what we’re trying to do, then where does it end?! Do I need 2000 lbs? Where do we stop? Do we just continue to build more creative apparatus to put more strain against us?
Answer: “No,”… because there is no amount of load that makes you more effective at communicating with your muscles. Contracting your muscles is an intellectual process that you must actively participate in.
You cannot just place more load against yourself to break a plateau; you must get better at contracting; you have to improve at inroading; you must improve communication to your muscles:
- ONLY then can you become POWERFUL!
- ONLY then can you predictably apply the type of stimulation that will result in adaptation.
- ONLY then will you be able to demonstrate your true strength potential and at a moment’s notice.
- ONLY then will you be able to behave as an advanced subject does, regardless of the equipment being used.
5) To post the video is simply because I enjoy the nostalgic aspect of Nautilus. It really was a great time, and we would not be here without it. I don’t believe that we should stay stuck in the past, but we do need to know our history to move forward.
I intend to post another video using the old Nautilus OME (Omni Multi-Exercise) and show a case where it can be used for a close approximation for something we’re doing.