Pose = crazy???

I did not make any assumptions about Asterix's educational background. If you inferred that from my previous post then that was not my intent. I merely pointed out that 10 is sometimes used in high school level classes and the reason why. Nothing more needed to be read into that.

He may have a college degree. But I do not think it is in math or a closely related subject because the critical analysis and logical skills are not representative of that.

I taught Calculus at a California University for several years prior to becoming a GPS engineer. I have a lot of experience with students at this level and the logical skills required to accomplish the curriculum.

I don't understand why you assert that my "conclusion is incorrect" when I have not offered a conclusion. All I have done is asked a question or two. Allow me to try this again in light of the information you have offered. You (i.e., Pose) seem to be saying:

1) There is a push-off, and it is comprised of muscular energy and a return or recoil from stored energy in the muscles/tendons. The muscular energy refered to is not the same as the stored energy. These two sources acting together are what create forward motion.

2) The afore-mentioned storage of energy is not perfect (you have not stated it explicitly, but your refernce to "spring" leads me to assume that the storage is due to the landing shock, i.e, the energy of the shock of the landing is stored in the muscles/tendons).

3) In order to return the leg back to its starting position in the stride, the inefficiency indicated in item #2 above requires the application of additional energy (i.e., "muscular energy").

4) The additional "muscular energy" noted in item #3 above is an "involuntary action".

Have I interpreted correctly so far? If not, please indicate which items are not proper (you don't have to go into detail, you can just say something like "Item 3 is not correct"), and I will ask further to rectify. I know this may seem a rather laborious process, but please bear with me. I'm sure it will grow fruit eventually.

Jim,

I have to prepare for a presentation.

I think it is important to clarify these matters about pose because I don't think it is appropriate that people should be misled about the truth. And if I am doing it I want to know it. Moreover, education never stops and I have learned a lot from reading through the threads. Hopefully, this can be done without further bashing.

I believe on another thread you said you have an engineering degree. If so then you are probably capable of getting much more concise and precise than what has been floating on this thread. If you have the time I would like to continue this tomorrow or Wednesday. Maybe we can present an accurate and more critical analysis of the Pose concepts.

Good. I will do what you are asking. I was hoping that you would take this approach. As I said a minute ago, I have to leave. But, I will look for you again tomorrow.

ST,

I guess there is a huge leap between knowledge in one area and another, so I can't expect that someone with a knowledge of calculus or engineering sufficient to teach at the university level to know even the basics of biomechanics. Still, it seems that the errors you have made in discussing these issues demonstrate a large gap in logic that surpasses any deficit you seem to see in the comments made by Asterix.

Your reading of the POSE literature is impossibly optimistic, giving the benefit of the doubt to Dr. Romanov by applying your own, more defensible interpretations to his ridiculous claims. Even then, you argue that the body needs to let gravity return the foot to the ground. This in fact does not happen. The foot returns through to the ground due to muscular actions. Look that this depiction of the running cycle from the POSE website:

http://www.posetech.com/pose_method/images/runningpose-250.gif

During midflight, the foot is quite high off the ground. If gravity was responsible for its downward trajectory once the hamstring was relaxed it would not fall any faster than the body's center of mass, and there would never even get in position to catch the weight of the runner. The leg is obviously swung forward and the foot takes on a downward component as part of this acceleration that is much greater than the force of gravity. After the foot moves under and in front of the center of mass it gets additional downward forces coming from the rotation of the pelvis and activation of the quadriceps to extend the knee in preparation for impact. Gravity has very little to do with this, as most of the downward movement of the foot far exceeds the downward motion of the trunk, which is normally less than 10 cm total vertical displacement.

Your argument that gravity was mostly responsible for this effect stated that

"You cannot raise your foot and employ muscular activity to bring it back to the ground unless you can appy force in a downward vector. To apply muscular force in a downward vector you have to push against something. What are you pushing against? Nothing."

As others have pointed out, this is a ridiculous statement, and it truly calls into question your ability to analyze the different biomechanical factors involved in human locomotion, university teaching background or not.

I don't recall ever saying I used 10m/s/s for physics calculations. I said that as far as everyday activities (like if you were wondering what the 'hang time' of a home run shot was or how long a penny dropped off a building would fall for) that the approximation was good enough since you're already losing the precision on most of your other variables.

That also includes applying it to running motions, so I don't see what your stats are good for here beyond showing that you have some good trivia (although wouldn't GPS be going to more than two decimals?)

Also...

I think this could be where JimFiore is going, but of all the cites I've seen on the POSE site (referenced many of them in this thread), I've yet to see anything that clarified the 'gravity does the work' line was only applied to foot fall.

Most of the cases there is no mention of the foot anywhere near. It is usually along the lines of 'lean forward and let gravity do the work'.

In fact, the very article currently being discussed (linked by JHuffman), it says "While this happens the body is moving (rotating) forward by gravity force. "

That to me seems to be talking about the body itself, not the foot. The only nearby mention of the foot is to pull it up from the ground (which would be working against gravity, not letting it do the work).

JY

You might think about being a little more cautious before make assumptions and start casting dispersions about people you do not know. One of the benefits of growing old, and something not uncommon amongst curious people that are my age is the opportunity to study many things. I never said math was my only area of formal training. I just said I taught Calculus at a California University, you made your own inferences from that. Math is the language of science. Being proficient in it has made it easy for me to understand and learn many other disciplines.

In addition to my degrees in mathematics and in computer science, I have completed at the collegiate level 1 year of exercise physiology, two years of biology, 1 year of chemistry, 2 years of physics, 2 years of philosophy, 4 years of English, 1 year of drama and 2 years of French. I have produced proofs that advanced the fields of Math Analysis, Differential equations, Combinatorics, Set Theory and computer science. I am proficient in electronics (have to be in my current business). I have a General Class contractors license, and over 1 million square feet of construction performed under my direct management (I have studied structural engineering). I have used my initial education in Math and subsequent teaching experience to become proficient in many fields in the last 30 years. That is a lot of time and I used it to satisfy my curiousity and better myself in life. My informal training is even more extensive then my formal training. Oh, and I still get requests to teach part time which I sometimes do.

Today I own my own business and outside of the primary function of the business I am a paid consultant to a fortune 100 company. I would be shocked if there was anybody on this forum that doesn't know this company and bet a significant number of people here would like to work for it, I would do it for free because it is so much fun. They hire me to research concepts they are commercializing in fields outside of my core area of education because they know that if I say I can prove something then I can.

Please, do not bash me because you think I am bragging about my past. I know many people much brighter, more capable and more successful then me, and I learn from them frequently. My very good friend who is probably more intelligent then me produced the Stephen Hawking videos. I just want you to understand that I am probably capable of understanding and analyzing the concepts being discussed here.

Now I haven't formally said that I can prove anything about pose. When and if I do you will know. I have made some simple statements about gravity (you can't run without it, if you jump off the ground it brings you down), I shared my personal experience, I said I haven't YET found anything in pose contradicting the laws of physics, and pointed out what I consider to be errors in logic, interpretation, inference, causal relationships etc. As a teacher I understand that we often use metaphors that are not perfect to help people achieve the desired understanding/result and it is necessary to identify and separate them when analyzing the statements on the pose site.

Lastly, a logically correct statement can be made by anyone whether they have an arms length of credentials or none. I have met many scholastics that couldn't reason themselves out of a box and many people with nothing more than a high school education that were standouts in their field because they had extensive experience, an informal education and quite frankly were just good. If you have a degree in biomechanics then that can be very useful here, or if you don't but have studied extensively and can present your understandings in a way that others can understand then that can also be useful.

I previously said that before I knew about pose I had experience with someone that taught a similar technique (before Romanov even had an education). I am now very curious about the mechanics. I believe that a fundamental change in my form would have got me the sub 4 mile time I was close to but never achieved. A few of my very succesful training partners seemed to have used something similar to pose. They were a female Olympic marathoner, a 2:16 male marathoner, and a sub 4 minute miler. When I was a youth those were excellent performances.

I would like to have a discussion about pose with people that park their egos at the door and truly want to entertain a discourse that could better the knowledge of all me included. And I will do this offline if that is the only way it can be accomplished.

Jim, Jeremy, Asterix

I hope you want to jump in on this. Perhaps starting a new thread might be a good idea.

Things went well today and my time is spoken for through Tuesday and very likely Wednesday. I can't do much useful analysis when I am this preoccupied but I will make my time available when I am not.

If you are not interested that is okay. Just let me know so I can start my own informal study elsewhere.

Odd, since the main reason I chimed in was that I was put off by your assertions about Asterix. And I quote, "He may have a college degree. But I do not think it is in math or a closely related subject because the critical analysis and logical skills are not representative of that." Ibelieved that to be an unfariassessment, because I had not noticed any logical flaws in his argument. Nor could I see where he had made any patently false statements, such as your assertion that "You cannot raise your foot and employ muscular activity to bring it back to the ground unless you can appy force in a downward vector. To apply muscular force in a downward vector you have to push against something. What are you pushing against? Nothing."

I would like you to point out where in my statement I cast "dispersions" (I think you meant "aspersions") about you. I did not contest whether you had taught at the college level, or whether you were succcessful in other avenues of your life, only that you obviously should spend more time listening in this discussion then challenging others. I did this based not on my perceptions of your qualifications, but on your statements that exposed gaps in knowledge and flaws in logic. I would think that a man who has obviously achieved expertise in at least one area would understand the gap between casual understanding and expertise.

Good I look forward to your insightful contributions.

I, in contrast, do not have a contractors license.

Although I've listed my academic experience in one other thread, I prefer not to. I do not expect anyone to accept my thoughts based on my credentials, but on the basis of sounding as if I know what I'm talking about. It appears that providing you with a detailed rebuttal to your suggestion that gravity was responsible for the footfall during running was not overly impressive to you. In fact, for someone supposedly here to learn something you basically blew off everything I said that challenged your assertions, and picked out one nugget that you mistakenly asserted was in support of your gravity theory. Well, accept it or not, I can't see how my academic degree or experience with biomechanics would change your reaction.

If you really are open minded about it, let's go.

ST wrote:

Jim, Jeremy, Asterix

I hope you want to jump in on this.

I thought the starting point was the 4 straightforward questions JimFiore posted above (3:19pm on Aug 14). It looks like he's just asking for a yes/no or correct/incorrect answer for each.

You wanted to start fresh, so going from those questions we can at least ascertain where the basic contradictions lie.

I agree, Asterix. That was my intention; to clarify and distill major points before continuing. Further, I am interested in the responses of other Pose advocates regarding these four questions because I think it would be incorrect to assume that Mr. ST speaks for all of them.

Jim and Asterix,

The article I posted clearly answers the question to whether there is a need for a thoughtful push up during running. Next question?

Jhuffman wrote:

Jim and Asterix,

The article I posted clearly answers the question to whether there is a need for a thoughtful push up during running. Next question?

No, No No.

Since you seem to be the leader of the Pose people, answer these 4 questions individually. No posts to articles on the Pose site.

Answer. The. Questions.

1) There is a push-off, and it is comprised of muscular energy and a return or recoil from stored energy in the muscles/tendons. The muscular energy refered to is not the same as the stored energy. These two sources acting together are what create forward motion.

2) The afore-mentioned storage of energy is not perfect (you have not stated it explicitly, but your refernce to "spring" leads me to assume that the storage is due to the landing shock, i.e, the energy of the shock of the landing is stored in the muscles/tendons).

3) In order to return the leg back to its starting position in the stride, the inefficiency indicated in item #2 above requires the application of additional energy (i.e., "muscular energy").

4) The additional "muscular energy" noted in item #3 above is an "involuntary action".

Jhuffman wrote:

Jim and Asterix,

The article I posted clearly answers the question to whether there is a need for a thoughtful push up during running. Next question?

As the post immediately following yours implies, it is your explanation and your words (and those of ST and Gatorade and whoever else) that needs to be seen.

As ST has suggested, there seems to be differing opinions as to what POSE is saying. He seems to read it as saying one thing while you and others read it as saying something else (whether the 'gravity doing the work' refers to moving the whole body in a horizontal direction or just returning the foot after the pull back being a big one).

We can save a lot of electrons if we can establish what it is you are trying to argue.

If you are unable to answer the straightforward questions without having to link to the site, then just say so and we'll carry on with those who are able to enunciate the concepts themselves.

He won't stop wrote:

3) In order to return the leg back to its starting position in the stride, the inefficiency indicated in item #2 above requires the application of additional energy (i.e., "muscular energy").

4) The additional "muscular energy" noted in item #3 above is an "involuntary action".

I'll take a stab at the leg returning to its position. This is achieved through the “pull”. The use of the hamstrings after the foot has left the ground. Once the foot/leg is at the apex (because of pull and recoil), the foot will drop properly until the next pull. I won’t go into the technical details of why, but there must be some sort of momentum at work in order to get the foot out in front of the body. I will let people debate that. There is certainly no need to voluntarily activate the knee to get the foot out in front according to POSE.

The pull is one of the debated issues among POSE advocates. Jack of the POSE forum advocates “thinking pull” before the foot hits the ground. However, he will go on to say little pull is needed and some of the leg traveling up is caused by recoil. He may also admit the hip flexors may get involved, but only slightly and not to think about it. There are other coaches, such as Claudia, that will admit pull before landing is needed for negative foot speed and to help the foot get under GCM properly. Dr. R thinks this is bad and will cause strain on the hamstrings.

"Does Pose claim that a person can run across level ground without pushing off (i.e., applying no horizontal force component), instead relying on gravity to move foward (i.e., letting "gravity do the work")?"

Pose claims that there should be no VOLUNTARY push-off. There is sort of a "push off" that is generated by ground reaction force and muscle recoil. This is what is enough to regain the lost height. I write the n-th time already: it matters what is being done, and not what happens.

Gatorade wrote:

Pose claims that there should be no VOLUNTARY push-off. There is sort of a "push off" that is generated by ground reaction force and muscle recoil. This is what is enough to regain the lost height.

So, in terms of the four statements I listed, would your answers be true/agree to each? I'm not sure.

You see, here is where we get into trouble. You state that there is "sort of" a push-off. What is "sort of" if not a vague, imprecise modifier? It leaves much to the imagination, ambiguity arises, and we cannot discuss the matter with accuracy. Second, please define what you mean by a "voluntary" push-off. Am I to take this as the leg muscles do not contract under the control of the runner (for example, "voluntary" meaning the sort of control one would apply to leap vertically from a standstill)? Third, although I take it that "muscle recoil" refers to the stored energy of landing, I am not sure what you mean by "ground reaction force". Landing on the ground causes the reaction of storing energy in the legs, but as you have already included that item (aka, muscle recoil) I must assume you are referring to something else (or you're being redundant).

The more precise we are, the fewer misinterpretations there will be.

Gatorade wrote:

"Does Pose claim that a person can run across level ground without pushing off (i.e., applying no horizontal force component), instead relying on gravity to move foward (i.e., letting "gravity do the work")?"

Pose claims that there should be no VOLUNTARY push-off. There is sort of a "push off" that is generated by ground reaction force and muscle recoil. This is what is enough to regain the lost height. I write the n-th time already: it matters what is being done, and not what happens.

As i wrote pages ago, the POSE 'pull' is a whole body action that includes activation of numerous stabilising muscles and the extensors of the support leg in addition to the 'obvious' activation of the flexors of the swing leg - the push is a part of that voluntary action. By all means say that you don't 'focus' on the pushing, but you cannot say that one aspect of the action is voluntary (the pull) and at the same time another aspect of the same action is involuntary.

So you are also claiming that all the power for the push off comes from stored elastic energy, with no additional muscle work to offset energy losses?

The push off is not created by the GRF. The GRF occurs as a result of applying force the leg.

The GRF occurs as a result of applying force **to the ground through** the leg.