Fore Aft Balance and Boot Delta and Forward Lean

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Fore Aft Balance and Boot Delta and Forward Lean

Postby Jadey » Mon Jan 23, 2017 1:29 pm

Hello All, I am wondering if there is a good way to self assess what the correct boot delta and forward lean should be for my particular anatomy (also in advance please excuse me for rambling on a bit) I am about 150 lbs, 5'7 and this year I will ski at least 100 days. I would say that I am pretty advanced skier, I ski everything but most enjoy anything off piste. At the moment I live in Chamonix and free ski all day everyday.

I recently listed to a podcast by Tom Gellie (a former colleague and teacher of mine) who had a chat with HH, and they talked a lot about boot alignment which rekindled my interest in an issue I was having last winter (anyone who is interested can find the podcast here http://www.podcastgarden.com/podcast/globalskiing, I highly recommend it Tom also interviews many other great skiers such as Reilly McGlashan, Richie Berger and Paul Lorenz). A few years ago I got a pair of Dalbello Scorpion 130's with a foam liner and booster straps, when I originally purchased the boot the fitter put in a heel lift because I have somewhat limited dorsiflexion. At first I felt as though this helped my skiing by putting me forward. Sometime after that I did a level 3 CSIA course and exam and although I passed pretty well I was having difficulty keeping in contact with the tongue of the boot. Later on a friend of mine commented that she thought I was low in the hips and we discussed the heel lifts and she thought they might be putting me too far forward and causing me to compensate by sitting back. I immediately tried skiing without them and when skiing back to back laps with and without I did feel more centred with out the lifts (putting the lifts in now makes me feel like I am wearing high heels). I have also noticed that I feel a little better balanced on my skies that have a zero binding delta compared with skis tight a small delta angle (although this is very subtle and I am not sure if I am imagining it or not). I am planning on doing more experimentation with spoilers at the back of the cuff vs. attached to the liner tongue to adjust how my tibia sits in the boot.

I know it sounds as though I may have answered my own questions but I am not at all convinced either way at this point, does in anyone have any tips or ideas on cues I can use to self assess my for aft alignment. I should say I have plenty of time at the moment, I have nothing to do but ski everyday, what I do not really have is a lot of money to spend on boot fitting. Besides, many of the boot fitters that I talk to do not really provide the kind of in-depth service that I think I probably need to get this really dialled in. Any advice would be much appreciated.
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Re: Fore Aft Balance and Boot Delta and Forward Lean

Postby Obrules15 » Mon Jan 23, 2017 4:32 pm

If you have a relatively smaller femur length/lower leg length ratio it would explain why a lift to correct your dorsiflexion would put you off balance to the front which would then cause you to lean back. I think one of the options would be heel lift for dorsiflexion and reverse binding delta or toe lift to compensate for the increased forward lean caused by the heel lift.

I've had a ton of fore aft issues over the years and just recently started to play with my setup. For boot forward lean I basically created a thick spoiler made up of layers of sticky bootfitter foam and when I determined it was too thick peeled layers off of it until I felt like I had the capability to achieve fore-aft balance.

Basically I would take a run, peel of a layer, take a run, peel off a layer. You've got to start with too much because removing a layer is easy to do at the bottom of a run, whereas adding a layer would be trickier. I also used the foam to create different height of heel lift inside the boot. That couldn't be changed without taking off boots but it still works if you're willing to remove your boots.

That was easy to play with, binding delta not so much, though a credit card under a heel or toe can be an option depending on your bindings. I know the Dumont shop sends people out on demo skis with +/- ramp delta to help dial these things in.
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Re: Fore Aft Balance and Boot Delta and Forward Lean

Postby chris719 » Mon Jan 23, 2017 5:13 pm

I am working with the same issue. I suspect that if you are very far off, you might be able to self-assess, but it's far from a sure thing. If you are looking for fine tuning or you can't feel the difference immediately you should get someone to video you for comparison. You probably should get video anyway.

Too much heel lift can result in quad burn. If you go too far with the toe lift you'll be pushing plastic and bending at the waist to compensate. Between the extremes it is very hard to tell what is technique related and what is equipment related.

I have seen a few theories on how to predict fore-aft alignment on dry land, but I don't know that any of them actually work. The only way to get a good assessment is by skiing with someone or via video.
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Re: Fore Aft Balance and Boot Delta and Forward Lean

Postby Max_501 » Mon Jan 23, 2017 7:29 pm

Very complex topic and I couldn't do it on my own.

fore/aft Balance - Ramp Angle - Delta angle - Heel Lifts etc
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Re: Fore Aft Balance and Boot Delta and Forward Lean

Postby deicreo » Tue Jan 24, 2017 5:14 am

Hi Jadey,

few remarks for consideration as I have also had some similar issues with fore/aft balance.
I always wanted to have Dalbello Scorpions, but they have vary small open of the upper cuff. Not good for someone who has large muscular calf.
Your sweet spot for fore aft balance should be between the toungue and the back of the boot. While skiing we are repositioning our feet with regrads to the hips.
During transition the hips are behind our feet, our legs are flexed and the edges can be changed. Then our new outside leg lengthens and at the apex you should be at the max extension
of your outside leg. This is the moment when your hips should be even or ahead of you feet. Since the transition you need to moving forward by pulling your feet back.
Note, that traditional ski instruction reverse the movement sequence. They stand tall at the transition and somewhat crouch at the apex. Some feature of the ski boot in combination with lower leg built can vastly inhibit ability of getting to the front of the ski. In my case (5'11'' hight, muscular legs, especially calfs) I found out that zero binding delta works very well. When I bought Head isupershapes with freeflex binding (5mm delta) my quads were burning. On older Voelkl Speedwalls Sl (0 or 1 mm delta) I could ski comfortably. Thus I installed 5 mm toe lift in all of my freeflex bindings. But that accomodation changes only the bent of your legs since this is the outside the boot work. As the other stated, for tall skiers with long femurs the heel lift is rather helpful. The other very important factor is the upper cuff angle. Although your scorpions, nominally are rather straight boots with something around 14 degrees, they also have deeply hiden heel socket which might give bigger than nominal forward lean. If you have too much of forward lean, it closes, dorsiflex your ankle and you will not have any range of motion left. To open the ankle you can put the heel lift inside the boot (AFAIK Scorpions comes with interchangeable ramp board). Notice the difference between inside the boot accommodation and outside. Now, I have inside the boot heel lift and outside toe lift. Further up, I will straighten my upper cuff to open the ankle even more. I ski in Head Raptors RS 140.
Fore/Aft is much more complicated because you have 3 joints at which you can flex or extend. Prior dealing with this you need to have proper lateral alignment. And... probably the most important factor is the strength of the posterior chain muscles and hip extensors. But this is something I am in the process of figuring out.
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