So help me out here. When we talk about pressure, edge angles, rotating masses... are we discussing chemistry? Weather? Pharmacology?
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You turn the skis - vs - The skis turn you
So help me out here. When we talk about pressure, edge angles, rotating masses... are we discussing chemistry? Weather? Pharmacology?
Funny that you mention this. I was at a PSIA Cert Clinic and one of the Instructors in our group was a Physicist from Los Alamos (highest per capita Phd’s anywhere). The clinic leader knew of his background and asked him to delve into the physics of skiing, needless to say most of us were lost at “potential energy.” Don’t get me wrong, it was interesting but he had a mastery of physics and of skiing while most of us were just struggling with the later.
Teaching In northern NM your audience is very likely going to to be someone with a physics/math background, so I’d be even less comfortable trying to get too deep. I’ve been following this thread, trying to glean information to better understand the topic, and there has been plenty of good info.
I think the real trick is taking that info and using it to develop/tweak progressions for the level of skier you are working with and doing so in a way that does not sound like a physics discussion. It’s like teaching kids (and to an extent adults) make it fun so they don’t know they’re learning.
The Tech Talk at Taos, done often by Doug Decoursey, a PSIA examiner and the author of a couple books on skiing is always informative. If you get a chance to take a mogul clinic or class with him, don’t pass it up!
That is physics. Sadly, too many people avoid studying physics in high school, and few excel at it. It cannot be avoided; you need to talk about edge angles, and force is what makes you turn, but it's a slippery slope, and most folks eyes will glaze over before you get even a little ways down that slope, unless you happen to be a good physics teacher.
Analogies to clients life experience (riding a bicycle, going around a curve in a car, etc.) involving the same physics can work better than an explanation of angles and forces.
That sort of depends on what our starting assumptions are.
Imagine a hardtail MTB tire but let's make it out of ski materials. Wood, fiberglass , ptex on the outside. Like an old wagon wheel or like an original penny farthing tire before pneumatics were adopted.
Pretty bumpy, right? The energy goes right into your body, right?
Now let's switch back to our modern tire. Much nicer ride, right? But wait a minute. It's made out of two of the most insulating, low-heat-capacity materials we know (thin rubber and air). The ski core structure is much better at heat conduction than the rubber and air of a tire but the tire rides much nicer. How in the blazes is that possible?
Our smell test has therefore painted itself into a logical corner - low heat conductance, low heat dissipation materials provably absorb more of the nasty harsh vibrational energy than the high heat conductance ones.
So, maybe our starting assumptions are wrong. Maybe the amount of energy isn't a concern, maybe we're coming in well under any sort of material cap. Maybe the response rate of the material itself is a concern. Maybe we need to adapt the material to the specific vibration we're actually experiencing as harsh, and if we do that without damping out stuff we don't need to worry about then total energy caps are also not something to worry about.
Wait, what is this? Piezo crystal? A material whose response rate (aka mechanical impedance) is electrically tweakable on an almost continuous curve? Sweet, that will come in handy.
I think we're picking nits here. I can't find any posts saying that jumping into any form of complex explanations about physics or anything else on the hill is a prerequisite for better skiing and coaching. 'Simple' makes frequent appearances though. It'll snow in a couple months...
Every ski lesson I ever had talked about pressure and edge angles. Gravity, fall line, "Centrifugal force", momentum, friction, acceleration, speed, dynamic turn. It's all physics. All of it. Soup to nuts. What we're discussing here, what I'm trying to get across, is that it doesn't have to be white lab coats, wire rim glasses and pocket protectors. Or Greek letters and equations. Or number crunching calculations. Or glazed over eyes. The dynamics of skiing involve fairly easily understood concepts and fairly easily understood explanations.
And so you make my point, perhaps without realizing it. An analogy of riding a bicycle can explain what's different about a dynamic turn without getting all technical. It takes a common everyday experience and relates it to several important concepts: The effect of speed in a turn. The concept of rotational dynamics and the inward forces involved in a rotating body. That those inward forces must be offset by aligning your body (COM) to the force to stay balanced. All of which is explained by pointing out how the bicycle rider leans in a turn, and we all have experienced that and know that is true.
It isn't that you don't explain angles and forces, it's how you do it that makes for good teaching. The problem is when the instructor doesn't understand it, and explains it wrong, even in simple terms. That's why the brows were furrowed in Taos. Or does understand it, but somehow can't speak about it in layman''s terms, or even easier than that.
Whether they know it or not, good ski instructors are good explainers, good isolators, good demonstrators, good analogy makers of the physics of skiing.
There you go.
Virtually all of our clients could care less about the physics of skiing. They want to have fun and, perhaps, get a bit better. Or have someone to hang out with. Or whatever. They really don't want to hear about how there really is no such thing as centrifugal force that's pulling your to the outside of the turn, instead its centripetal force that pushing you inside.
Make it relatable to the average client who most probably dropped out of math, let alone physics, before finishing high school.
Mike
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I believe one or more occurrences of the word "alleged" should be inserted within that sentence.
I have taken over 30+ ski weeks there and regularly free skied with groups and instructors. I don't believe I have ever been overwhelmed by the "physics" involved in the technical discussions and I am one of the biggest dumba** floating around.
Thread Starter
TS
When I teach beginner groups of adults, I even avoid using the words "parallel" or "perpendicular," just in case I have someone who is math phobic in the group. A ski club member I once knew told me the reason she avoided taking lessons was that instructors used terms like parallel and perpendicular. She said she shut down any time they used confusing words. People are different.
The brows were furrowed because a non-quantitative ski instructor was attempting to explain physics to a bunch of physicists.
A little off topic but lots of thought provoking posts!
One of the preliminaries in developing a lesson plan or coaching strategy along with MA is to evaluate the students "current level of understanding" & utilize that as a jumping off point. Words like "parallel" & "perpendicular" would be just fine with the Los Alamos crowd but probably not with a group of kindergartners.
Begin with the simple, then move on to the more complex only when your audience is thirsting for it.
Remember, teach for success!
As for "you turning the skis or the skis turning you" I can relate to either depending on my mood, current political stance or the time of day
.(7 pages! Wow, can't believe I'm posting after page 2)
Jim, you better turn the skis there!
If not, I will leave it to a higher power
What words do you use in their place?
Thread Starter
TS
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Good for people who get things visually, but for many that doesn't work.
To me, "parallel" is not a complex or mathematical word. I agree that I would never say "perpendicular" though.
Thread Starter
TS
That example refers to beginners keeping skis parallel when side-stepping uphill. Everyone I've ever taught can indeed see and do, at least for that first uphill step. But for many, with the second step muscle memory steps in and they turn the uphill foot, ski on, to point uphill and you know what happens then. So I have to tell them to watch their feet at first ... because they slide backwards continually. Many just can't overwrite muscle memory without visually checking.
So far I've not found anyone who doesn't at least understand this information when I deliver it visually.
They do however guess the "bowling ball line" wildly wrong sometimes. (I don't like calling it the fall line for beginners because of the reference to falling. I could call it the "gravity" line but avoid that too because of its association with physics.) So what to do when they guess wrong? Some people even have difficulty identifying downhill as opposed to uphill. Really.
Once they guess the bowling ball line and place their poles on the ground to show me their guesses, I show them how to sidestep uphill with their skis "like this" (perpendicular to their guesses for the fall line). I tell them that side-stepping uphill should work if their guesses about the bowling ball line are right. I show them what happens if their guess is wrong, and how to adjust the way their skis point so they stop sliding forwards or backwards. If I have to use a word, I use "match." Make your skis match like this, not like this. I never use parallel, perpendicular, or gravity in these initial discussions because of that math-phobic friend of mine in the ski club years ago.
It is amazing how difficult some beginner adults find this task to be. Patience and compassion are called for. Can't wait for ski season to start!
So far I've not found anyone who doesn't at least understand this information when I deliver it visually.
They do however guess the "bowling ball line" wildly wrong sometimes. (I don't like calling it the fall line for beginners because of the reference to falling. I could call it the "gravity" line but avoid that too because of its association with physics.) So what to do when they guess wrong? Some people even have difficulty identifying downhill as opposed to uphill. Really.
Once they guess the bowling ball line and place their poles on the ground to show me their guesses, I show them how to sidestep uphill with their skis "like this" (perpendicular to their guesses for the fall line). I tell them that side-stepping uphill should work if their guesses about the bowling ball line are right. I show them what happens if their guess is wrong, and how to adjust the way their skis point so they stop sliding forwards or backwards. If I have to use a word, I use "match." Make your skis match like this, not like this. I never use parallel, perpendicular, or gravity in these initial discussions because of that math-phobic friend of mine in the ski club years ago.
It is amazing how difficult some beginner adults find this task to be. Patience and compassion are called for. Can't wait for ski season to start!
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LF for first timer's sidestepping, sure - parallel is easy to see. However as soon as they are gliding, making straight runs, wedging, etc. they shouldn't rely on visuals, particularly looking down. To me "matching" has no meaning and "parallel" and "wedge" (or for kids, sure, "french fries" and "pizza") are needed words. Worrying about the reaction of one person to the word may have kept you from using it for all the others who it may have helped.
"Keep your skis parallel" is a very useful verbal command in my opinion.
"Keep your skis parallel" is a very useful verbal command in my opinion.
Thread Starter
TS
I know. We are probably on the same page here, Steve. Once I have established a relationship, I sometimes ask if anyone has a problem with me using a word such as "parallel," and then I go ahead and use it. You are right, I have responded strongly to my friend's fear of such words. But I don't think it has hurt my teaching, just opened up my awareness of some potential for mental blocks that might be hiding out there in the minds of the clients I encounter.
People in lessons also have difficulty working with the terms uphill ski - downhill ski, inside ski - outside ski, tip - tail. Oh, and don't get me started with flex and extend. "Like this... show me..." works pretty well in most situations for doing something the first time.
Then we need to move from thinking about it as a movement, to feeling it as a sensation.
People in lessons also have difficulty working with the terms uphill ski - downhill ski, inside ski - outside ski, tip - tail. Oh, and don't get me started with flex and extend. "Like this... show me..." works pretty well in most situations for doing something the first time.
Then we need to move from thinking about it as a movement, to feeling it as a sensation.
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