fore/aft Balance - Ramp Angle - Delta angle - Heel Lifts etc

[John Mason]

I am the Guinea Piggy

I skied Saturday at Nubs with a shim under my back binding. It helped a lot. I have a second shim to try once I get some longer binding screws.

I suppose once I get too much I'll feel that too then I can back off.

In TAS (the athletic skier book) fore aft balance it put ahead of canting in the alignment circle. I guess like SMIM it's whatever is most important for that individual. Witherel adds, though, that if fore-aft is off then canting assesments on slope will be off. Thus his recommendation to get fore aft corrected first before canting.

[Guest]

Bump...hoping that Ydnar will post the promised method to measure fore/aft alignment.

[ydnar]

Sorry to take so long to get back. I'll have a new computer today or tomorrow and be less frustrated when trying to post. Here is my take on evaluating fore/aft alignment

In skiboots buckled the way the individual skis in them with a much wider stance than they would normally ski with (shoulder width or a little more) I have them do a full squat, all the way down untill both knee and hip joints are fully flexed. Some people will lose their balance and fall backward trying to do this so be ready to give them a hand to prevent this. Others will be able to get into the full squat by holding their arms out in front of their bodies. Some will be able to reach this position and bring their hands into their chests. For those who can't reach the full squat position and bring their hands into their chests use some kind of a spacer under the heel of their boots untill they can achieve this position. What I want from this group of people is to get them balanced so that they can maintain this position without straining but I can easily push them over backwards. I then measure the height of the spacers (using one and two mm thick plastic for the spacers makes this quite easy) and put a heel wedge of that height into the boot under the liner. Then its off the the snow for further evaluation and feedback on how it feels and looks. For those who can reach the full squat with their hands on their chests it is very important to do the "pushover test". If they fall backward when I lightly push their chests then I do nothing. If they can resist being pushed over backwards then I use spacers under their boot toes untill they can be easily pushed backwards. Once I've determined how much "toe lift" they need the "fix" is more complicated. It is often difficult to raise the fore part of the foot inside the ski boot so I will try to lower the heel of the foot by grinding the boot board or the boot itself (or going to a boot with less built in ramp angle). Another way to address this (and prehapse the easiest) is to put a spacer under the toe piece of the binding but here you have to be carefull not to take the binding setup out of Din. Once the "fix" is in place its time for further evaluation on snow.

Everyone I have ever done this with has liked the results and has been able to ski better after the procedure.

yd

[ydnar]

Left something out. To determine the lift needed in a boot for someone aligned back you have to measure the difference between the heights of the bindings at the toe/ball and at the heel. Subtract this figure from the total lift needed to determine just how much heel lift is needed.

yd

[LewBobSki]

ydnar, Great info. I am a tall guy with skinny legs who has always been in the back seat. I have been adjusting new boots, with a lot of lift in the boot, and spoilers behind the cuff to get me normal forwared lean. I keep getting closer to a balanced position, but never quite there. BTW, I have never been able to squat, in or out of ski boots, without falling over backward.

Wednesday I was experimenting at Loveland and put another shim behind my calf. It felt great. No more rounding my shoulders and reaching with my hands to keep me balancedl. I am really excited about getting up to the slopes again to confirm that I am finally balanced-I did this at the end of the day and only had 2 runs with the new setup.

I have been skiing for over 40 years and have always had to compensate for deficiencies in my boots. What a feeling to finally feel aligned!! LewBob

[John Mason]

I'd be one of those to fall without the lifts. And if you have to put your hands forward to balance, then you find the butt goes back too. Better to raise the heel slightly.

I read that post and first thought - but what about the delta angle. Then I read your next one.

I'm skiing next week, and now that I have put in some binding shims, I'm going to remove the calf insert so I can be balanced but also be more upright. I should get this dialed in by the all mountain camp.

[LewBobSki]

Just make sure you have the shims with you. You may need both the calf shims and the raised heels. LewBob

[John Mason]

Your description of how you feel sounds like I feel. I'll keep the calf inserts and try it both ways.

Wanna ski any next week? See my other post. SCSA will be with us on Friday and Saturady and Hobbit perhaps also on Saturday and maybe Sunday.

[mkgil]

Fascinationg, ydnar. Does the forward lean of the boot affect things? Appears that John, Piggyslayer, and I were onto something.

Eager to hear your results, John.

Michael

[piggyslayer]

Ydnar

I tried to do that in ski boots (I assume without skis) and cannot.

Do I understand your instructions correctly? Do you want butt to go all the way down to touch the ski boot and torso to touch with the thighs? I can do that easy to reach parallel (horizontal) thighs or even lower, but not all the way down.
In this position, in my ski boot I am not dorsiflexed enough forward to be able to balance.
Both butt and most of my torso are behind my boot heel thus the CM is behind and I believe this got to be true for everybody who has boots without a LOT of forward lean.
This is how my Dalbellos are positioning my body, not how my body is.

I believe, I have no problem pressuring the ski tips without any upper body movements. If anything I am pressuring the tips too much. I also did not have problems with performing the mkgil squat test.

Note, I did some googleing on art and body proportions and it looks like ideally hip to knee and knee to ankle are the same and both are 2 heads big.
Here is interesting link:
http://www.maths.adelaide.edu.au/people ... /pm10.html
This tells me that an average butt will get very low in this exercise and will be behind the boot. If there is not a lot of forward lean on the boot, the CM has no chance of getting under the foot.

I am sure I am doing something wrong, please advise.

Robert

[mkgil]

Ydnar's diagnostic technique worked very well for me. After enough heel lift, I could do his test. As I pulled my arms back in a deep squat position, I was just balanced. I could have been tipped backward easily.

My skiing definitely improved. My wife corroborated for me that I wasn't bending at the waist. I certainly felt my hips solidly under me.

I am, however, interested in Robert's point. Forward angle of the boot must have some impact on diagnosing. My Daleboots have 12 degrees forward lean, and that may be important.

Over to you ydnar.

Michael

[LewBobSki]

Your description of how you feel sounds like I feel. I'll keep the calf inserts and try it both ways.

Wanna ski any next week? See my other post. SCSA will be with us on Friday and Saturady and Hobbit perhaps also on Saturday and maybe Sunday.

John, How did it go? Did you need to keep the calf inserts? And how was your trip? If you are coming out again this year let me know and I will see if I can meet you. Lew

[John Mason]

I'm pretty comfortable on 2 shims without the calf inserts. I only got to ski a short day with that setup (about 1 hour) as my son's marker bindings fell apart after a minor collision. So Greg and my brother kept skiing whilst I helped my son get his stuff to the local shop.

But, that 1 hour of skiing was - well - refreshing. I was not fighting to get forward or back, but felt very centered. At first, the sensation was so different it was almost as if something was wrong. All of a sudden the things I had brought in to my skiing as an adaptation, if done sent me too forward. Now that was a feeling I had never had before.

The next week I was working with PMTS with my youger son's girlfriend at Holiday valley and, because the 1100xrc's just edge so well, they are not the ideal ski for demoning some of the beginner moves that result in brushed carves, I got out my I75m's that have the shallowist delta angle of the skis I have. Gosh, it was difficult. I was no longer centered and needed to always be pulling my feet back just do demo little traverse drills.

I'm skiing Sunday at Keystone so I'll have a number of hours to play with the setup more. So far I'm estatic! Also at camp this week I'll have a lot of objective eyes too. In the videos I got of the setup, I look totally different to myself. Once, in fact, I thought my son was me because of a slight back seat he had going. Then I saw the green poles and realized that pic was of him - not me. (my brother was taking pics). I looked quite balanced fore to aft which I almost never did before. Felt good - looked good - seemed good.

[LewBobSki]

John, What are you using as shims? How thick are they? Lew

[Joseph]

What on earth are you guys doing? Would somebody please explain to me the relationship between a full squat and skiing. I may not have been around doing alignment as long as Harald, but I still have yet to see anyone doing full squats as they come down the slope. Why would you want to base your equipment on the ability to do so. If you're squatting when you ski, you're doing something wrong. Furthermore, if you're putting anything in your boot such as a heel/toe lift, you're changing the angle of your foot inside the boot. It might be a good idea to know what you're doing exactly. As harald has said many times on this forum (possibly even in this thread) fore/aft balance is fluid and must be adjusted from turn to turn by the skier in high performance skiing. If you're interested in changing fore/aft balance, start by pulling your feet under your body and not squatiing when you ski. If you still can't get your feet under you, look at the forward lean on the boot--it's probably too aggressive. Remove spoilers, add support to the tongue. Heel and toe lifts should be added by trained alignment technitions only after a proper assessment of a person's feet and lower legs. If none of this works, then get a more upright boot. If fore aft balance still hasn't improved, it's probably something in your skiing, not your equipment--There is no magic pill! Finally, if you want to change the ramp angle of the entire setup, do it under the binding. That should only be done by a professional though--one who has the ability to see the relationship between your skiing movements and your equipment. Somebody certified to work on bindings. Seriously.