Loading the top of the turn

[Philpug]

You should take a look at the Reid thesis.
Pressure should not be in the top half of the turn and there should be pressure after the fall line. The study even shows that pressure does sometimes increase after the apex or gate. The study used world class racers btw.

@ScotsSkier is a top ranked Masters Racer, @Doug Briggs is retired US Ski Team, they are world class racers. What Scots is saying, creating energy for 0-90* creates speed because the energy is going down the hill as compared to 90-180* where the energy is going accross the hill which is against the fall line. As Scots says, for a recreational skier, it might feel good but it is not always the fastest, what is the end goal, feel or speed?

I am not an instructor and am working on my own demons but what Scots says, as much as I can wrap my mind around it, makes sense.

 

[BS Slarver]

Two likes for @ScotsSkier and @Doug Briggs, well explained and a picture or video is worth a thousand words, or multiple pages of,
" what does it feel like " ... never mind !!!

IMO In both racing and modern skiing, starting to load-ing at the top of the turn certainly has its place.
Top of the turn was the question, yes ?
Top 1/8 - sometimes, first quarter 1/4 yes. Top 1/2 you better hope so !
Not wanting to fuel the fire here but Line, speed, pitch and tactics, just to name a few variables would need to be added to the conversation. My .02

 

[Art of Skiing]

Why would you guys call that loading or pressure?
Pressure, to me, is about where you want to bend the ski the most. The ski will bend the most from the fall line onwards and a ski hardly bends at the top of the turn. Of course there will always be pressure in a turn no matter where, even at the top, but this happens due to the skiers weight and tipping. So why is this relevant?

I attached a picture of the Reid thesis. This shows where the ski is bending the most and it clearly shows it's not the top of the turn. Just after the apex of the turn is where the ski will bend the most, which means there is a lot of pressure on the ski. The picture shows the radius of the CoM and the outside ski in a 13 meter course set btw.

 

[ScotsSkier]

Why would you guys call that loading or pressure?
Pressure, to me, is about where you want to bend the ski the most. The ski will bend the most from the fall line onwards and a ski hardly bends at the top of the turn. Of course there will always be pressure in a turn no matter where, even at the top, but this happens due to the skiers weight and tipping. So why is this relevant?

I attached a picture of the Reid thesis. This shows where the ski is bending the most and it clearly shows it's not the top of the turn. Just after the apex of the turn is where the ski will bend the most, which means there is a lot of pressure on the ski. The picture shows the radius of the CoM and the outside ski in a 13 meter course set btw.

Hmm, so you now want to try a different argument?????

Good to see you are now agreeing with those of us who do understand it though....

I am somewhat confused as to where did anyone suggest the pressure is max at the top (start) of the turn????. You do know what the bell curve I referenced for the pressure distrubution through the turn is ???

 

[Art of Skiing]

I am not trying or saying anything different, nor am I agreeing with you lot.

Doug Briggs and BTS683 - you get it! The pressure should be in the top half of the turn, ideally peaking at the 90 degrees point and then decreasing. i like to think of the pressure distribution as a bell curve or a triangle. As you come past the apex the pressure should be easing off ready for the switch to the new ski. One of the biggest issues - and time loss! - i see with athletes is increasing the pressure in the bottom half of the turn, and fighting gravity and losing time all the way. Even more obvious when you watch non-racers free-skiing, the pressure seems to increase between 90 degrees and 180 degrees! And when they are doing it people think they are really doing well and loading up the ski - and yes it can feel really good!- (and usually accompanied by the body following the ski tips!) but in reality they are killing speed rather than building it. It may look pretty to the layman but certainly does not work in the course. By pure coincidence I was working on this with one of my athletes this morning in a GS course. He is a strong skier and a PSIA level 3 but still struggling to start letting off the pressure to accelerate the ski which is killing his race times.

And the equal loading does NOT mean equal pressure on both skis. In ski racing we still load the outside ski, aiming for 80/20 - 90/10 most of the time - not really that different from the Karl Schranz era in that respect!

"No pressure in the top half of the turn" ?? That maximum snow reaction pressure ( 3.5 G's ! ) has to be just after transition, of course . IE in the top of the turn. I note Ligeti's violent upswing of both arms to effectively increase his weight at that point, improving his edge set.
Coiling must produce the 3% energy gains sometimes noted, but it's main advantage is faster edge set, IMHO.

Here are some tracks of a well known WC racer.

I interpret the depth of the track to indicate the relative pressure the ski is applying to the snow. It seems to me there is pressure developing above and diminishing below the apex of the turn, with the maximum just about at the gate.

Where did anyone suggest that max. pressure is at the top of the turn? I will refresh your mind for you, look at the post of bawbawbel. I even quoted it for you and underlined the part you have to read. I see him saying pressure is just after the transition at the top of the turn. And you know what the funny thing is? You actually liked the post, even though it contradicts your own words. Just to get our definitions straight, the top of the turn, just after transition is way before the apex or fall line in my book.

Yes I know what a bell curve is. Now as to why I disagree with you and Doug as well is because I disagree with pressure being at its max. at the apex all the time. On the flats or easy course sets, then yes, but on the steeps, or in tight course sets there is definitely pressure after the fall line/apex or gate, which means there is pressure from 90-180* as you put it and it means pressure is not immediately decreasing after the 90* point. Even max. edge angle is not always at the apex of the turn, but sometimes below the apex of the turn. To summarize, I am disagreeing with pressure always decreasing below the apex, because it simply is not true, which has been shown by studies and if you closely look at WC ruts you will see the same patterns of late pressure. A ski bends far more below the fall line than above the fall line, hence decreasing pressure below the apex in a tight course set makes no sense at all. That is when you would be fighting gravity. So no, you are not slow when you increase pressure for a short period of time after the fall line, WC skiers do it too.

I added a picture of some ruts in WC and look at how deep these ruts even until far after the gate/apex/fall line. This is because pressure was not immediately decreased from the fall line/apex onwards... And look at how late in the turn his ski's actually start turning. Most of the turning happened after the gate.

And yes, of course pressure will always be developing above the fall line and deminishing below the fall line, in that sense I agree. The problem is that saying something like that is like saying you start tipping above the fall line and you flatten the ski's below the fall line. That statement tells you absolutely nothing about pressure distribution and hence does not tell you where the pressure is at its maximum.

 

[john petersen]

There are ideals and there are tactical choices made for reality. In an ideal course in our minds, we strive for certain performance levels at certain points in a course and in each turn. In reality, when "pushing the envelope and hauling it back in" (quote from the Right Stuff....ski analogy to astronaut analogy of pushing the limits ) ideals are kept in mind but tactical choices and holding a line become more important in the moment. Ingrained practice and body movement memory are relied upon to achieve the most efficient technique possible. The art beyond the technique is speed generation.

Im just throwing out a guess at the above, though.....

In an ideal turn, in our minds, we want to THINK about loading the skis as early in the turn as possible, right?.....where that actually happens in any given turn around any given gate is determined by several factors, some or hopefully most of which we have some control over.

Ligety's arm movements to me, anyway, are a tactical aid in generating speed through some angulation, but more importantly through a momentum move that helps him in a way that eludes my level of description at the moment!.....It seems to help set him up for the apex with a strong and stable upper body, but its more...it actually seems to propel him down the hill a bit.......its a speed generator of some sort.....there, it still eludes me!

Think of the outcomes different folks are striving for when they ski, where they ski, and in what conditions. The ideal performance for the end of the turn is pre-transitional no matter what level skier we are talking about, on most any terrain. otherwise you get "edge lock up" with beginners in the wedge, "tail wash" with intermediates and "chattering" with upper level recreational skiers. I cant talk for racing, though I have seen a need for developmental skill blending through childhood into young adults. (I do see significant changes with most U19 kids....for the better...very impressive)

"Letting go" of your turns is a big topic with upper level recreational instruction (and from the sound of things, in racing too) and for that to happen, guess what part of the turn we have to start thinking about?......With shaped skis, and the latest theories on ski engagement, things can happen much sooner than they used to. We just have to get on board with where and when and how we are applying the skills we already have to different parts of our turns, and get D.I.R.T.y.

JP

 

[bawbawbel]

In simpler terms, would this be described as getting high enough to be looking towards the next gate as you begin to finish the turn? That way you are taking advantage of the ski rebound back into the fall line?

Or how would you describe the pressure distribution with relation to turn shape and relative to a gate?

Maybe it was decided that to have any ski energy to use for rebound at that point meant a slowing had taken place in the bottom of the turn by overturning .
Looking towards the next gate allows a lossless rotation to be added from the upper body.
Anything that will assist the earliest possible generation of pressure.
We might expect that transition occurs at point of maximum flex. Not so with Ligeti, he is already extending!

I quoted directly from the badly written Reid Thesis. It should read "maximum pressure was obtained AS CLOSE AS POSSIBLE to transition.
A lot of rubbish and red herrings from boffins rather than skiers.

 

[BornToSki683]

Art, there will nearly always be more pressure in the bottom of a turn compared to the top of the turn, especially on the steeps, because the bases of the ski are facing more towards the center of the earth. However the more that a racer can do to manage that, the faster they will be. Every millisecond of resisting gravity is lost time on the course. So while you may be correct about sensors registering more pressure below the apex, I hope you still acknowledge that the fastest racers are trying everything in their power and capability to minimize that.

The top of a turn, on the other hand is very difficult to create pressure the steeper it gets because the base of the ski is facing away from the center of the earth. In reality not much pressure is needed in the top half, some people I feel overdo their quest for pressure up there. But the thing is, it's actually quite a bit more difficult to generate even a little pressure up there, especially if you are avoiding "pushing" movements to do it.

So the irony of the situation is that a skier needs to most of the time be very proactive to do certain things that will create needed pressure up top, and do proactive things after the apex to minimize pressure, with an idealistic goal of creating the bell curve that has been mentioned.

At the apex is where you want the most pressure, even if gravity is creating more pressure after it.

Outside of a race course it can be super fun to swoop across the bottom and resist gravity and in super steeps, manadatory to do so; but on a race course that will be slower.

I think pressure creation in general is often overrated and man handled the wrong way. In order to engage the skis and get them to perform, there has to be enough downward pressure to penetrate the edge into the snow surface, after that its all about balance over that ski and having sufficient edge angle. No more pressure then gravity alone is needed for that but when you're upside down at the top of the turn with bases facing away from gravity that is a lot harder to get. It it can be gotten with appropriate balancing movements to position the CoM over the BoS in a way to be there. Many people are deficient in this regard. Get over it drill is exactly about this.

All of the multiple G's of pressure that come during a turn are a result of reactionary forces from the snow, reacting to two things: momentum of the skier and the force of gravity. Ideally if we want to go fast then we want to minimize the pressure after the apex so that gravity can pull us down the hill faster. Meanwhile there is also often a requirement to be displaced laterally across the hill to get over to the next rise line of the next gate. Reactionary force at the apex is what does that. And above and below it too also can contribute but again, resisting gravity below the apex slows you down.

Thus the ideal is to get the most reactionary force you can above and at the apex, while minimizing it below the apex, if your goal is max speed while navigating a course.

 

[ScotsSkier]

You should take a look at the Reid thesis.
Pressure should not be in the top half of the turn and there should be pressure after the fall line. The study even shows that pressure does sometimes increase after the apex or gate. The study used world class racers btw.

.....;.
........

And yes, of course pressure will always be developing above the fall line and deminishing below the fall line, in that sense I agree. .........

So which argument are you trying to use this time???????

And what Doug, myself (and indeed everyone else in this thread!) was pointing out was what we try to get athletes doing as a default position. I don't recall any of us saying this happens ALL the time, indeed it happens less than most of us as coaches would like! . However it is still the fastest way for a racer. The longer you hang on to the ski below the middle of the turn the more you are fighting gravity and, equally important, the harder it is to start the switch to the new ski. Usually results in digging big ruts below the gate, fighting the hill and gravity then being late into the next gate and having to make a big movement (usually costing more time) to make the switch a lot later than you should have.

Are there times when you hold on pressure below the gate? Of course! If the set is taking you away across the hill, it will look like this. But you then need to look at what the shape of the turn is and where the actually belly of the turn is.! It may indeed be below the gate! And on other occasions a racer may decide that it is quicker for him to run a straighter line at an earlier gate and scrub some speed below the gated with late pressure or a stivot because that gives that racer a quicker line. It is often a good tactic coming on to a pitch (for example coming over the road on Fascination at Squaw) to scrub a little speed to get a clean entry rather than carry too much heat over it then struggle to make the next gate and be fighting for a few gates to get back ahead of the course, losing time all the way. (Look at Travis Ganong's winning run in the US nationals SG in 2013 at Squaw). And of course any racer that is pushing hard is going to run a less than perfect line at a few gates in a course. However they are all still staritng form the same premise that they strive to reduce pressure past the middle of the turn to gain speed.

But anyway, you keep telling yourself about your preferred theories, I will stick to the real world of helping my athletes get down the course quicker!

 

[Mendieta]

So which argument are you trying to use this time???????

And what Doug, myself (and indeed everyone else in this thread!) was pointing out was what we try to get athletes doing as a default position. I don't recall any of us saying this happens ALL the time, indeed it happens less than most of us as coaches would like! . However it is still the fastest way for a racer. The longer you hang on to the ski below the middle of the turn the more you are fighting gravity and, equally important, the harder it is to start the switch to the new ski. Usually results in digging big ruts below the gate, fighting the hill and gravity then being late into the next gate and having to make a big movement (usually costing more time) to make the switch a lot later than you should have.

Are there times when you hold on pressure below the gate? Of course! If the set is taking you away across the hill, it will look like this. But you then need to look at what the shape of the turn is and where the actually belly of the turn is.! It may indeed be below the gate! And on other occasions a racer may decide that it is quicker for him to run a straighter line at an earlier gate and scrub some speed below the gated with late pressure or a stivot because that gives that racer a quicker line. It is often a good tactic coming on to a pitch (for example coming over the road on Fascination at Squaw) to scrub a little speed to get a clean entry rather than carry too much heat over it then struggle to make the next gate and be fighting for a few gates to get back ahead of the course, losing time all the way. (Look at Travis Ganong's winning run in the US nationals SG in 2013 at Squaw). And of course any racer that is pushing hard is going to run a less than perfect line at a few gates in a course. However they are all still staritng form the same premise that they strive to reduce pressure past the middle of the turn to gain speed.

But anyway, you keep telling yourself about your preferred theories, I will stick to the real world of helping my athletes get down the course quicker!

Thank you sir, I do need a beer right now So, am I right that these concepts are the same as what Lito Tejada refers to as early weight transfer and dynamic anticipation? The second half of the current turn should set things up so that the next turn is "ready to go" as soon as we start changing edges (not that I, personally, do this properly)

http://www.skimag.com/ski-performance/breakthrough-with-lito

Cheers!

 

[ScotsSkier]

Yes Leo, in essence that is a similar approach. In the second half of the turn you are reducing pressure and starting the transition to the new ski for the next turn. A good drill for that, as shown to me by a USST coach is to do a series of turns lifting the downhill ski as soon as you finish the turn to help you get comfortable with the early move to the new ski. It forces you to become more comfortable doing something that feels very unnatural at first, learning to commit to the new ski. The other huge plus to starting that early switch for a racer is that as you come through the inevitable ruts below the gate you are not pressuring against them and getting bounced and with an earlier switch you have much more time to set yourself up for your preferred line at the next gate. Simple in theory but takes a lot of work to get there!

 

[bawbawbel]

I note that nobody has commented on my redneck dismissal of the Reid dissertation.
Unfair comment by me. It is, after all, a doctoral dissertation and the most thorough investigation of ski turns that has ever been done.
A hundred million data points. Maybe someone will write some cunning computer programs to extract something that race coaches have missed.
I did notice often unexplained differences between right and left turns. Maybe something to work on with the individual racer?

 

[bawbawbel]

I got Lito's latest book on soft skiing for aged skiers. Disappointed. Thought even that it might have been ghost written. Illustrations are just shadows.
His trademark dynamic anticipation is hardly mentioned past the standard "relaxed back muscles and still upper body" dogma.
So much left unsaid

 

[ScotsSkier]

In simpler terms, would this be described as getting high enough to be looking towards the next gate as you begin to finish the turn? That way you are taking advantage of the ski rebound back into the fall line?

Or how would you describe the pressure distribution with relation to turn shape and relative to a gate?

My simple description of the desired pressure distribution is increasing to the mid-point of the turn and then progressively decreasing. This can and will change depending on line, turn shape and other variables of course.

I am hesitant to describe the pressure relative to a gate as the turn shape is usually more dependent upon the position of the previous and the following gate, and ideally you should be looking 2 gates ahead as well. However, in a straight forward rhythm GS set, I would normally expect the pressure to be reducing as you come past the gate and the switch to the new ski should be already starting at the gate. One of the most important points to get across to new racers is to think of the gate as basically the end of the turn rather than the midpoint. When it is treated this way they can start to understand the high entry line and arcing the turn rather than running straight at the gates in a zig zag fashion.

 

[markojp]

Game on in this thread, eh?

 

[Doug Briggs]

@ScotsSkier , I agree about gates and turns. A sequence of gates determines the optimal line. You don't want to blithely turn at each gate and assume you'll be fast. The line you take to get there and then follow once you've 'arrived' is much more important than 'turning at the gate'.

 

[ScotsSkier]

Yes, we are in violent agreement Doug!

 

[Philpug]

3...2...1..and we are done here.