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FREE WEEKLY Expert Advice. Login here every week to read Dr.Romanov's advice on various training related topics. You're welcome to email your questions to support@posetech.com and we'll make sure to cover the requested topic. This section is updated every Tuesday.
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March 08, 2005
PERCEPTION IN POSE METHOD OF RUNNING. LEANING
The importance of developing perception of leaning comes from the fact that we don't have a possibility to recognize the angle of leaning through any measurements and the only tool that we have is our perception. It is related with different things . One of the most important things is deviation of our body from its balance on support. We are basically leaning out of balance. We must first develop our perception of getting out of balance and being able to return to it. The next step would be developing our perception of getting out of balance and not being able to return to it. This is the range. Where we are in this range is strictly dependent on our perception, and our perception of how far we can go out of balance and still be able to return to it depends on our ability to bring the foot under the body.
There are two very important parameters here. First is timing of pulling the foot from the ground. And the second is frequency of doing it or cadence. Both perceptions are equally extremely important to be developed, and are intrinsically connected with each other and with leaning. I was surprised recently, when I got an email from one of our coaches, Ward Swallow, from Las Vegas, to find out that somebody could distinguish these parameters so succinctly. Swallow's Ph.D. in psychology probably went a long way in contributing to this. He wrote to me that cadence, in his opinion, is related with speed and pulling is related with timing. That's absolutely right, and we need to keep this in mind.
Leaning itself has two parameters to be distinguished: one is the degree of leaning and the second one is the angle of velocity of leaning. Given that there are no interferences, the degree of leaning depends on horizontal velocity of the general center of mass. For example, using the simple formula from Physics: F = mg · sina, we can find the horizontal acceleration of the body and then the time and velocity of the distance. Using the formula S = atē/2, we can determine how fast we can run some distances with a certain angle of deviation. For example, just 5 degrees of leaning allows us to run one mile in 4 minutes 6 seconds. But there is no such thing as constant leaning. With each stride we are losing the lean and then recreating it again. This is what is not readily apparent, when considering this issue, and serves as the reason for confusion and misunderstanding. The second parameter is the degree of freedom to fall. You could be in an optimal position to fall, however, if you are holding yourself and resisting falling, you will not fall. You are reducing the angle of falling and the speed of falling.
The misunderstanding in this matter arises from thinking that the maximal ground reaction force causes acceleration, and also from the general fear of falling and reluctance to allow it to happen. In reality, acceleration happens as a result of falling and peaks, actually, when the ground reaction force is in decline. Contrary to popular belief, the biggest demonstration of acceleration is seen after the ground reaction force has diminished. This is the crux of the issue. This is where one's perception of leaning will determine optimization of this physical fact. Horizontal acceleration depends on one's freedom of falling and his skill or ability to pull the support foot from the ground on time with the lean. But how do we do this? Only through perception: perception of deviation.
Our body acts like a pendulum with the pivotal point located on the ground. We know from biomechanics that 62% of the bodyweight is located above the waist. This fact allows us to understand how leaning works as well. But to do this we have to have a precise perception of releasing our body to this lean and changing support to be able to repeat this falling again.
How can we learn and perfect this? What are the necessary elements? Perceiving the edge of falling - that spot where we feel we can no longer continue to fall from and we need to change support. With speed and fatigue this perception is diminished, and causes us to miss this point. Once you miss this point, you revert back to using muscle efforts. The muscle tension that results from this, diminishes our ability even further and we revert back to a system of holding that interferes with the falling continuum.
There are several drills that can aid us in feeling this "edge of falling". Once again, it is important to begin the drills in the Pose stance and take a moment to feel the pressure or feel where your body weight is on the balls of your feet.
- Allow your body to lean forward to the point where you have to change support
- Do this first in place against a wall, and then while moving forward and changing support
- Do this in place with a partner providing resistance by holding the hand on your chest
- Lean into your partner's hand as an integrated unit, keeping the pendulum effect in mind, and be aware of how the pressure increases as you lean more
- Have a partner push you on your back, and resist several steps, then let go and do not resist the push any longer
- Run with two fingers on your belly button: having pressure on the belly button indicates leaning forward
- Run downhill on slight angle of inclination - which will provide excessive gravitational pull - without activating any muscle's tension in the upper body against falling
- Do the same exercise on a flat course
Dr. Romanov
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It's correct Jordan,
Dr.Romanov
It is almost like, the body is a lever, and it translates the downward force of gravity into forward force, simply because there is something beneath what is behind you, but not in front, so by continualliy toppling and using bipedal transfer, it changes.
Dear Mr.Hogler,
You got very good answer from Dean, who is taking an example of the sailing boat movement. Do you need more explanation? In a coming book of triathlon technique it would be presented more detail about this matter. Thank you.
Dr.Romanov
Holger, think of a sailing boat. If the wind (a force, corresponding to gravity in running) comes in at right angles to the boat then how can it propel the boat forward? We put the sail at an angle (correspong to angle of lean in running) then the boat will experience a sideways and forward force vector. However the keel (corresponding to the ground in running) stops sideways movement so the boat moves forward at right angles to the wind.
Whoa - this really blows my mind now! Could someone please help me out?
Dear Mr. Romanov,
up until now i dismissed all this gravity talk as an attempt to help Pose runners to get the *image* of letting themselves fall forward and keep themselves from falling flat on their face by moving their legs ingrained in their minds. I've been training myself with this method successfully for quite some time now.
In this article, however, you do the math to show how gravity actually moves the runner forward. See, I'm certainly not another Albert Einstein (although we share the same birthplace ;-) ) or Richard Feynman, but i wasn't exactly a slouch in my college physics, either. So what puzzles me is that, *by definition*, horizontal acceleration is orthogonal to the force of gravity, which always, invariably accelerates you towards the center of the earth. Of course, orthogonal vectors are things that are completely independent of each other and so orthogonal forces may be varied without influencing each other, not even the least tiny bit. To cut it short now, as long as you try to move forward on a flat surface, there is no way gravity will ever help you to accelerate in the direction of your intended movement. And no clever device whatsoever (not even the human body) can change the direction of the force of gravity.
Could you please help me untangle the knot in my mind?
Yes, Vincent,
it is an artificial example, but close enough to reality to help us to explain how the force of gravity works and how far we are from our potential, if we can handle and use only a small part of this force. As I mentioned it in the article, with 5 degrees of constant leaning and acceleration it would be possible to run 1 mile in 61 seconds.
Dr.Romanov
This calculation to explain 4:06 mile with 5% lean seems very artificial. The time over 100m with 5% lean is correct only if there is constant acceleration. With constant acceleration the average speed over 15.3 seconds is reached after half that time. After 15.3 seconds the speed is twice the average speed. With that speed one would be able to run a mile in 2:03 or the remaining 1509 m in 1:55 for a finish in 2:10. What makes your calculation appear artificial is that you choose to use the average speed over 100m. Why not 200 or 50m? Why not use the finishing speed after 50m or 100m? This calculation is distracting us from reality.
I believe it is much more worthwhile to consider the equations just as a demonstration of how force and acceleration can be produced by leaning.
Your calculation assumes a constant angle of lean and a completely rigid body. In reality, as you described so well in your article, there is no constant acceleration or constant lean. We can produce lean and acceleration by allowing the body weight to move/fall over the support foot without resistance.
Yes, gentlemen we are talking about realistic things. As I mentioned it before, there is no constant acceleration in any running except the initial running from the blocks by sprinters, which last about 5-6 seconds when they reach maximum speed. At this acceleration they have some periods when the deviation goes to 45 degrees, but that doesn't last long. In order to consume gravity to such a degree you have to be incredibly skillful. So the assumption goes as follows. At a smaller degree than 5, we can maintain acceleration for around 100m and then maintain it for certain time. Calculations are as follows: F=mgsina, a=9.8 x.0872=.85456m/sē, S=atē/2, if s=100m, then t=square root/200x.85456=15.3 sec. Then, average speed is 100/15.3=6.53m/s. We can run with this speed 1609m(one mile) in 4:06 sec. 1609/6.53=246.4, which is 4"06 per mile. If we could run with constant acceleration coming from 5 degrees of deviation, we would run 1 mile in something around 61 seconds which is beoynd our abilities yet.
Dr.Romanov
This is very helpful for me. Especially the connection between lean, pull and frequency. My pulling is a too late, and frequency too low (especially at lower speed). I think that I can fix my problems, and with leaning at lower speed, by improving timing and frequency of the pull.
About the math:
If a=g.sin(5) and S=atē/2 then a distance of 25 km would be covered in 4 min and 6 seconds.
This assumes constant acceleration and speed at the finish would reach an unrealistic V=a.t of 210 m/s. That leads me to believe the 4 min 6 seconds mile with a 5 degree lean is based on real races and lean not math.
Could you show us the math how 5 degrees yields 4 minutes 6 seconds. What is the "a" in S = atē/2, angle or acceleration? Thanks.
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