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# Balance - Page 2

Quote:
 Originally Posted by Skidude72 Balance defined: When the sum of all forces acting on a skier (ie the resultant) at a given point in time acts through the skier's COM and BOS at that same given point in time the skier is in balance. That is it...nothing more, nothing less. HOWEVER, the key to understanding or applying this to skiing, is to understand that you do not always want to be in balance..ie transition.....further, just becuase you are in balance, does not necessarily mean you are doing things correctly....ie a when a top spins it is in balance, but if you are spinning like a top, that is not good, unless of course you intend to during some aerial manouver. Another example is antcipatory moves.
That is probably a correct definition of balance but in order to make it dynamic I would like to change that definition to cover not only "a given point in time" but a continuous time period. The problem is not really to sum all the forces through the CoM and BOS but to be able to sum up all the forces at any given time and react instantly and subconsiously on any change in forces present.
Quote:
 Originally Posted by therusty I wouldn't call that the "whole secret" to skiing and balance. Anticipation and countering moves can be seen by everyone. That's not a secret.
I was refering to "anticipatory" movements and not antisipation as in countering. The whole secret to skiing and balance in general is the ability to manage anticipatory movements in combination with quick reactions.
Quote:
 Originally Posted by therusty Using your core muscles to resist movement away from center is the "secret" part of balance because you can't see that happening.
Sure you can see that happening. Angulation for example. But not everyone knows its a balancing move so that might be the secret. Anyway, skiing is no big mystery. Everything can be observed and analyzed. Think MA. Take 10 good PISA instructors and have them perform MA on the same person and they will come up with the exact same result. Note, you dont have to know any of this to be a great skier.
BigE,
I am not sure you got my point. I did not mean to call standing still (btw I said standing still on one foot) dynamic balance. I meant to convey the fact the standing still on one foot requires minor muscular contractions to maintain an overall appearance of balance. Look down at your tendon in front of your ankle from the tibialis anterior muscle and watch the dynamics that are going on to create balance, that is not a static situation in most of us. I agree that if you look at someone standing still from afar, the look to be in balance, I maintain that they are always balancing, not in balance.
Greg
My point is that dynamic and static balance already have real definitions.

The muscle movements you make to stay in balance while standing on one foot don't make it dynamic. Dynamic balance requires that you are moving. eg. standing on a rolling skateboard or on moving skis. Dynamic balance does not refer to shifts between balance/imbalanced states.
I challange you to stand on one foot without making movments to maitiain that stance. Hence using your definition movement to maintain balance. Being in motion only complicates dynamic balance however dynamic balance is occuring while on one foot. In comparison to a two footed stance.
This is a good discussion. I should have pointed out that I don't understand balance and most of what I say is more of a question.

Cgieb, athletic movement and those quick adjustments are a huge part of balance. I am thinking about a guy on a unicycle making all of those micro admustments. But I see him sitting tall with good posture, same with the guy on the rope with a pole walking tall. The picture of Herman M in the gate, he's stacked and 'ready'. You can't just muscle it the whole time, but core stability is a must for good balance. It seems to me.
Sorry, standing on one foot is not an example of dynamic balance, though it would be if you were spinning or making intentional movements eg. reaching with the other leg.

The following article provides the details for a test that measured static and dynamic balance in athletes:

http://www.pubmedcentral.nih.gov/art...?artid=1896078

Making movements to overcoming your heart beat and changes to position of CM due to breathing/circulation does not make balance dynamic. You will have to make some *balancing* movements when statically balanced, but that does not make for dynamic balance; if it did, all balance is dynamic, and the term static balance could never be applied any living thing.
I like the distinction between dynamic and balance while in motion. I wonder about motion and the inertia complicating things though. It may just be my perception but I find it easier to balance on one foot with some inertial momentum.
Quote:
 Originally Posted by BigE My point is that dynamic and static balance already have real definitions. The muscle movements you make to stay in balance while standing on one foot don't make it dynamic. Dynamic balance requires that you are moving. eg. standing on a rolling skateboard or on moving skis. Dynamic balance does not refer to shifts between balance/imbalanced states.
To stand upright on two feet requires balance. So does standing on one. Or lets say balancing on one. But standing on two feet requires balancing as well. So BigE wants movement. How about a person standing on two feet in a mooving train? Sounds a bit like mr Idaho carving rr-tracks !
Correction: Dynamic balance does not require standing, just moving through space. In this definition there is a point of reference outside the body that you change position relative to it. This definition assumes our body is like a particle in motion. a whole body definition.
Mosh's definition is more first person relative to all points outside the body. Balancing by movements of parts of the body instead of the whole body.
Add to that the idea that since we are on the Earth and it is spinning and we are all in motion relative to the sun. So since we are in motion we are always balancing in a dynamic environment. Which is why balancing an egg on it's tip is so hard and why water spins a certain way as you flush the toilet. Something we tend to ignore but shouldn't. Those motions and the forces involved are what we are trying to manipulate and balance.

I think you can see my point that one definition is inadequate when we talk about balance not only because of the previously mentioned point of views but also because it includes external forces acting upon our bodies and internal forces being created in our bodies.

All we can do is be clear about how we are using the term in our posts.
Quote:
 Originally Posted by tdk6 How about a person standing on two feet in a mooving train? Sounds a bit like mr Idaho carving rr-tracks !
Yes. That is dynamic balance.

There was a video somewhere of Melanie Turgeon in a tuck being pushed on a cart.
Thanks BigE for the athletic training article. Why are women basketball players so "inferior" at statice balance compared to the other athletes in the study? We need a follow up study...

Anyhow, I do not quarell with you if that is your point of reference, I just wanted to have some discussion regarding what I consider "fine motor" balance vs. "gross motor" balance. I submit that we are not far apart in this at all.
I am curious, how can we be in dynamic balance without the awareness and effort to be in what we are calling static balance on the platform that we are riding? When I am not feeling balanced (really quite often), functional ankle tension and awareness goes a long way to develop this dynamic balance.
Greg
Wigs,
congrats to your Rockies on the win tonight. They seem to be in balance.
Greg
Quote:
 Originally Posted by GR8TRN When I am not feeling balanced (really quite often), functional ankle tension and awareness goes a long way to develop this dynamic balance. Greg
And upward as well...the whole body
Quote:
 I just wanted to have some discussion regarding what I consider "fine motor" balance vs. "gross motor" balance
Maybe this leads to a distinction between involuntary and voluntary balancing movements. Involuntary movements being reflex driven and unconscious in nature, those muscle movements we make all the time, even when standing still.. Voluntary being those movements directly associated with our behavior goal and the movements we make to realize our goals.

Here's a quote from a scientific review of a book.

Quote:
 Behavioral goals are of great importance for postural control. Stance is not undertaken for its own sake, but in the furtherance of other, supra-postural goals; this is true even in young children (Slobunov & Newell, 1994). Stance is useful to animals only to the extent that upright posture facilitates the accomplishment of other goals (Riccio & Stoffregen, 1988). Roberts acknowledges that animals engage in a variety of postures (e.g., voluntary head movements, running, hopping), but does not say why this is so. Nor does he consider the possibility that supra-postural goals may influence not only the choice of postures but also the way in which posture is controlled (consider variations in posture that result from changes in mood).
Quote:
 Originally Posted by justanotherskipro I like the distinction between dynamic and balance while in motion. I wonder about motion and the inertia complicating things though. It may just be my perception but I find it easier to balance on one foot with some inertial momentum.
How about this for some food for thought.
Quote:
 In stance the human body functions as a set of connected inverted pendula (Stoffregen & Riccio, 1988),,,,One consequence of inverted pendulum dynamics is the existence of a direction of balance (usually, but not always, corresponding to the direction of unstable equilibrium). The direction of balance is a real, physical property of inverted pendulum systems, which has strong consequences for the muscular operations that are needed to establish and maintain balance,,,,Recent research (Riccio, Martin & Stoffregen, 1992) has shown that human orientation is strongly influenced by the direction of balance. This has considerable implications for the definition of "up" (Riccio & Stoffregen, 1988), and for Roberts' concept of a "behavioral vertical" (Chapter 6). The direction of balance changes frequently as a consequence of muscular forces, such as those exerted in locomotion.,,,,Thus, alignment relative to the direction of balance might provide a concrete underpinning to the largely undefined behavioral vertical.
Isn't it this recognition of the direction of balance that separates good skiing from hang on skiing? When I get my movement's directions supporting my balance directions, I feel like I achieve my best flow with the least amount of effort.
Quote:
 Originally Posted by GR8TRN I am curious, how can we be in dynamic balance without the awareness and effort to be in what we are calling static balance on the platform that we are riding?
Static balance has no movement component. So the platform is static, not just our relationship to it. So, as soon as the skis start sliding, we're in dynamic balance.

I had this same confusion -- in an edge-locked carve, the movements you make to stay in balance are very similar to the movements you would make to stay statically balanced.

The trick is to realize that the edge-locked carve has reduced the degrees of freedom of movement of the platform -- there is no lateral movement of the Base of Support/platform, so it greatly simplifies the balancing effort. Remaining balanced now feels more like a static balance exercise.

Add to that the forces while moving are larger than standing still -- you have something to resist, not just gravity, but momentum creating inertia -- so the body wants to keep moving in the direction of travel.

Once again, while the degrees of freedom of movement are not restricted, they are somewhat more limitted to preferentially choose the direction of travel. Even if your skiing is of the "hang on" variety.

Also, add to that the increased pressure under a dominant outside ski: the balance point on the foot does not wander so easily as when standing still -- like when we breath and our heart beats, we make balancing movements to compensate. These features now contribute in a purely minor way.

It may explain why female basketball players scored worse on static balance tests -- they are taller, yet have a similar sized base of support. When they stand still, the effects of circulation/heartbeat and breathing will be magnified over shorter and more squat atheletes. Yet, when they move, the additional inertial forces give them something more to work with -- perhaps just better feedback!
Thanks for the discussion BigE,
Sorry I don't get here everyday, I think your supposition regarding the poorer static balance for the female college basketball players vs. the soccer player holds well regarding their probable physical stature creating a more difficult statice balancing effort. anyway...

So let me get this straight, you are saying static balance involves no movement of the body or the vehicle/platform/skateboard/surfboard...

And dynamic balance is the body being static while moving through space on said platform?

Sorry to be so dense.

Greg
Almost. Dynamic can be the body trying to remain in balance while on a moving platform, or the body trying to maintain balance as it changes positions.

I think the key idea is that forces that challenge the CM to stay above the base of support are present in dynamic balance. They can be external, as the skateboard moves, or internal, as you change positions.

I suppose if you were on a platform that was moving, but so steadily and smoothly that you could not detect it, your balance would be considered static. Like us standing on the earth.
We could think of it as involuntary, versus voluntary balance. With static balance lying mostly within the involuntary realm. Dynamic balance lying within voluntary balance and defined by our behavior goals, and the movements we make to achieve these goals along with the manipulation of internal and external forces. Involuntary balance being more the reflex level and voluntary consisting more of learned habits and skills.

Off course it is not black and white and there is overlap and reliance between both involuntary and voluntary, but I think the real distinction comes with the behavior goal, and how we go about achieving this goal. Which is why our postures and movements change depending on the task at hand, and why what may be considered in balance when performing one goal will be considered out of balance for another.

Here's a definition quote that I think gives this some teeth,

Quote:
 Control of posture and locomotion involves regulation of the positions and motions of the various parts of the body in relation to each other and to one or more external reference frames in order to achieve the organism's goals.
I think voluntary or involuntary only confuses the issue.

I do not thing that the static balance can solely be defined by involuntary/reflex action. The example is walking on ice - an exercise in dynamic balance. If your foot slips on heel strike, your body will involuntarily attempt to stay upright by making some very dynamic movements driven solely by reflex.

The reflex wheeling of the arms and back pedalling of the legs are far from static balance movements -- they are involuntary movements that regulate the positions of the parts of the body in relation to each other and and external frame of reference to acheive the organism's goals.
Well walking on ice has a definite goal with learned habits and skills. This has been written on and studied by many learned people. Even they don't agree on every thing. Remember one persons confused may be another persons clarity. From what I have read, generally static balance is associated with more involuntary reflex goals, like simple maintainance of non moving posture, where as dynamic balance is generally associated with voluntary posture movements relating to habits and skills that serve an intended goal. This makes perfect sense to me and adds clarity to the issue for me. It is not hard to see how we may use involuntary reflex responses in support of our voluntary goal when things disrupt our goal temporarily. Though I don't see this creating any confusion in categorizing our balance needs, responses, direction, habits, and skills with respect to our movement goals.
Yes, it is a very reasonable way of looking at it, provided you know what the word voluntary means in the context of movement.

Some confusion can arise if the word "voluntary" is taken to mean "intentional". It's my own preference to keep this sort of discussion as far from intent as possible. It may be wrong to do that, but I fear people may think that intentionally standing as still as possible is and example of dynamic balance.

Which leads back to "there's no such thing as static balance", which is bogus.

### Balance

WOW Guys I had no idea balance was this involving, sincerely good thought provoking posts.

SoftSnowGuy. Yes a wide balanced stance does become important when skiing the Airpost bathrooms in the winter, in ski country, when there's snow on the tile and above all don't do any toe tapping hop turns!

Mosh. Like your early pg 1 definition and explanation.

From a non-pro skier (me). Beginners that show poor balance, I leave on the flats and really gentle terrain and we scoot -slide around a lot on one ski and two ski's. We hike up a little, do a bullfighters turn prep and side slip everywhere we can; forwards, sideways, backwards and both sides and diagonal. This eats up a little time but I don't think these beginners will have dynamic (while moving) balance without starting on Static and then real simple balance drills. One thing I do know is if I send them down the hill without any balance skills they will fall over like an improperly balanced vertical anything.

Thanks for the posts - good stuff!
Quote:
 Originally Posted by BigE Yes, it is a very reasonable way of looking at it, provided you know what the word voluntary means in the context of movement. Some confusion can arise if the word "voluntary" is taken to mean "intentional". It's my own preference to keep this sort of discussion as far from intent as possible. It may be wrong to do that, but I fear people may think that intentionally standing as still as possible is and example of dynamic balance. Which leads back to "there's no such thing as static balance", which is bogus.
So there is static balance? Lets take a statue of a standing person made out of stone. It stands in the park day after day, year after year all by itselfe. What kind of balance is that?
BigE, I agree with you on the dangers of misunderstandings that can happen in discussions like this. Sometimes posts bounce back and forth between general principles and terms, and sport specific principles and terms without maintaining relevance and context between the two. Which is why in my mind the voluntaryness of our goal driven movements need to come into the conversation relative to dynamic balance. It's pretty interesting stuff to dig into including the relevance of gait mechanics to our balance while skiing.

We are hard wired to involuntarily seek a vertical posture relative to gravity, yet our sport specific goals require that we actually violate and override this reflexive action and move relative to our goals, learning to utilize and be comfortable with "behavioral gravity" (forces of our movements and/or created by our movements and the skis action on the snow), or voluntary goal specific postural alignments. Even what our body recognizes and qualifies as effective balancing changes relevant to the voluntary goals we pursue.
Quote:
 Originally Posted by RicB We are hard wired to involuntarily seek a vertical posture relative to gravity, yet our sport specific goals require that we actually violate and override this reflexive action and move relative to our goals, learning to utilize and be comfortable with "behavioral gravity" (forces of our movements and/or created by our movements and the skis action on the snow), or voluntary goal specific postural alignments. Even what our body recognizes and qualifies as effective balancing changes relevant to the voluntary goals we pursue.
I'm not sure that the bolding is really the case. Our body still recognizes pressure on the soles of the feet and proprioceptive sytstem as providing strong balancing cues. When running, we REALLY like using a banked track, as it is so much easier to balance in the corners, even though the vestibular and visual systems say we are not vertical.

However, we ARE upright, and the proprioceptive and visual systems are verifying what the pressure and proprioceptive systems are telling us.

As you may know, I define balance as simply that the resultant of all forces acting on the CM points into the Base Of Support. This is often simply taught to beginners as "hips over feet" or prehaps, "ears over feet". Others say that this definition of "in balance" means not falling down. I agree. There is no need to romanticize it any further.

The implication of that is when describing transition as a toppling/launch into the new turn, the resultant will not point inside the base of support. If you are really toppling: our momentum has taken us "out of balance".

So, to fix this, the notion of "balance in the future" is developed to make it ok that you are out of balance right now. Worse, is that "good skiing" means I have to lose balance in each turn, playing catch with my CM. Meanwhile, my body tells me that this loss of balance due to the CM's momentum is really happening. This is not a cue I wish to override by calling it "effective", nor do I wish to teach that sort of imbalance as part of skiing. I know, you're probably thinking: "Here comes that four letter acronym!" but no.

We CAN manage our balance effectively without resorting to redefinitions of words like "balance". We must realize that it is the management of momentum that should be addressed during transition, and how that impacts our balance.

I've been trying to formulate this idea for some time, it's very much a "work in progress".

I like the notion of the two separate arcs -- the arc of the skis and the arc of the CM. I believe managing their relationship so that there are out of balance parts of the turn embeds a recovery move in every turn. I prefer that we manage the relationship so that the skier remains balanced through all parts of the turn, yet can still do very well in a race.

This means that the skier must be very aware of the inertial path of the CM -- and his instantaneous momentum -- and utilize it together with tipping and turning the skis to control precisely where the path of the resultant or "balance vector" is moving. These are "directional movements" -- movement of the CM with the base of support.

The inertial path of the CM is something you can feel as you move from one side of a turn into the other, largely because of the pressures along the bottom of your feet and other proprioceptive cues. I'm quite sure that your lower half can move to ensure that the base of support is always under the balance vector, and, you are still skiing very athletically. (Through tipping, pivoting, waist steering, brushing etc... and judicious control of the momentum of the CM)

There is no need to teach that good skiing has any recovery moves. So, if that is the case, there is no need to short circuit or redirect our attention away from being in balance all the time.

Sorry for being so long winded.

Hopefully, there is something of value in it....

Cheers!
This is why I have never cared for the concept of skiing out of and in to balance from turn to turn. I want to feel balanced all the time relative to my goals at the time. So for the most part when teaching I agree. How we balance/move over our skis relative to how the skis are working in the snow is what we need to focus on.
Quote:
 Originally Posted by RicB This is why I have never cared for the concept of skiing out of and in to balance from turn to turn. I want to feel balanced all the time relative to my goals at the time. So for the most part when teaching I agree. How we balance/move over our skis relative to how the skis are working in the snow is what we need to focus on.
I'm with you on that one for sure.
Quote:
 Originally Posted by mosh I personally would say that I spend more than 75% of my time in uniform teaching balance. Yes, absolutely balance can be taught. ...in PSIA the largest circle in the skill blending was balance, we would expect a much larger dose of information pertaining to the largest skill. However, I am sure there is way less info about balance in there compared to pressure, edging, or rotary.
All rotary all the time. If lack of balance is an issue, widen the stance for stability, not true, effective, dynamic balance. That's what has been taught to me. Pressure...somewhat on the fronts of the boots, mainly equal on both skis. Edging...never heard anyone mention it unless I asked.

Quote:
 I define balance as simply that the resultant of all forces acting on the CM points into the Base Of Support.
So, can there be balance if there is no Base of Support? Does a high diver with no base of support have any balance during that beautiful dive? How about that moment between turns when the skis are very light on the snow, or maybe actually in the air very briefly...no base of support? An innovative thinker about skiing once described skiing as the destruction of balance. We make a movement that takes us out of balance to begin a turn and make other movements that bring us back into balance to complete that turn.
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