or Connect
EpicSki › The Barking Bear Forums › On the Snow (Skiing Forums) › Ski Gear Discussion › Right amount of boot forward flex/ are most skiers in too stiff boots?
New Posts  All Forums:Forum Nav:

Right amount of boot forward flex/ are most skiers in too stiff boots?

post #1 of 9
Thread Starter 
I was checking out Realskiers new site and Jackson H reminded his readers that the turn starts by flexing the ankle. I clearly understand this notion... But is this really more about forward pressure starting in ankle and translating to lower shin--which results in pressuring the tongue? You really are not actually flexing the ankle forward 15 or 20 degrees or more in a stiff 120+ boot on a cold day. That's why I say-- isn't it more about forward pressure starting in ankle versus actually flexing ankle forward with meaningful travel?

My second question goes to boot flex. If you say that meaningful forward travel of ankle is the right goal and is important; particularly among all mountain skiers... I wonder if flex sweet spot for the vast majority of skiers-- let's say under 185lbs is in the range of 90 to 110 --notwithstanding the idea that I realize there is no single standard-- which is why I provided a range.

Obviously my question is driven by self interest--I call myself a perpetually budding expert. I am 158lbs, been skiing all my life, ski everything, but still working on technique, going to camps, ect. I typically ski in a 120 flex lange rx-- but maybe a 100 gives me more of that ankle flex that JH emphasizes.

How do you know? Would love to hear from Epic, Whiteroom and Lou if possible. Thanks
post #2 of 9
Actually, if the boots are soft, it will make it harder to pressure the front of the ski.
post #3 of 9

This would be a good question to ask on the boot forum, or the instruction forum. Not clear that a turn begins with flexing the ankle, if that's what the sainted JH said, but in the opinion of some respected members here, yep, we're going overboard with boot stiffness. Keep in mind that modern technique is all about lateral movement, and even moderate forward flex boots have very stiff lateral support. Plus modern liners are much better at transmitting force directly from foot to boot. IMO, forward stiffness is more about skier's body weight, habitual speeds (both of which produce force), and style (mashing forward is considered old school, however honorable). 

 

I'm 165. I've found that my racing improved when I dropped from 130 to about 122, and my recreational skiing is better at 110-115 than at 120+. These may reflect two different issues; racing demands rather precise timed foot movements inside the boot, which a super stiff shell actually slows by requiring more force, thus more time, and also racing can get very choppy/bouncy at speed, which a super stiff boot will transmit right back to your lower leg. So you spend more attention adjusting/surviving than turning. Our junior coaches actually sent around a letter asking parents to ease up on getting overly stiff boots for their kids.

 

For rec, a somewhat softer boot is better at absorbing shocks from bumps or variable soft snow and not transmitting every mechanical misstep back to the ski. 

 

Obviously, if a boot's too soft, then it becomes inefficient at transmitting force to the edge. Just a question of each person's sweet spot. And last, modern skis have become stiffer, to compensate for having shorter running lengths due to rocker, so the boot has to match the ski decently. A super stiff boot on a soft ski doesn't work, although it may be preferable to a overly soft boot on a stiff ski.

 

My .02, others will disagree, I'm sure. 

post #4 of 9

Flexing the ankle isn't about the range of motion of the ankle joint. It is about flexing the ankle joint to exert pressure on the boot cuff in order to transmit that energy to the ski. 

 

I've found it always helps to frame questions like this by starting with the question, "What effect is this having on the ski?" Because in the end, everything we do is to manipulate the skis. It doesn't matter what we do from the soles of our feet upward, if what's being done doesn't translate into the ski.

 

If you have a softer flex that allows a significant range of motion in the boot cuff, then you're looking at a situation where the energy you're putting into the boot isn't being transmitted to the ski. It's being absorbed by the boot in order to flex it. It's not until you have completed the flex of the boot that you're going to have any meaningful transmission of energy into the ski itself. A stiffer boot is going to allow for more direct, stronger transmission of your ankle flexion's energy into the ski itself. 

 

Now, each school of thought has its own benefits and drawbacks. The softer boot is more forgiving of small mistakes, as it absorbs them and doesn't transmit them to the skis. At the same time, it's less responsive, and you need to give more energy in order to make something happen. I compare it to the steering in a car. Compare the steering of let's say a 1992 Buick Century, to a current model Porsche 911. The Buick's steering is soft, you can give the steering wheel some pretty decent back and forth wiggle before the wheels do anything. The 911's steering is tight and super responsive. Every tiny movement of the steering wheel is going right through the steering mechanism and into the front wheels. In the Buick, you're sacrificing performance for ease of use and forgiveness, while in the Porsche, you are taking performance above forgiveness. Same with boots. Stiff is responsive, soft is forgiving.

post #5 of 9
Quote:
Originally Posted by freeski919 View Post
 

A stiffer boot is going to allow for more direct, stronger transmission of your ankle flexion's energy into the ski itself. 

 

Stiff is responsive, soft is forgiving.

Hmmm. Agree with first sentence as far as it goes, but I think you're missing most of the biomechanics that follow.

 

1) A great deal of the force is being transmitted at a vector to the toe that actually can be fairly far out toward lateral. So forward resistance becomes less relevant than lateral resistance early in the turn.

 

2) Direct transmission through a perfectly stiff shell isn't the whole story. If it were, we'd all be skiing 2" thick carbon shells. Nor is it about forgiveness, although that has real world significance.

 

More resistance requires more force to overcome. That force requires either acceleration or mass. In this case, it's being supplied primarily by the lower body. And it's neither instantaneous nor free (you're using your leg muscles and your COM). If you don't have the time, or don't have the mass or the muscle energy, you end up not flexing your foot inside the boot correctly, let alone flexing the boot sufficiently. Which screws up your turn. Even if you do, you end up spending more time than you should on getting the forward flexion when bam, you need to be already getting out to the side. 

 

3) The Buick 911 comparo is, uh, traditional, but again, it strongly implies that real studs drive cars that are seriously taxing, only real studs need apply. (FWIW, and for Phil's benefit), I've driven over quite a lot of time a 58 Buick, a 65 Buick, and several 911's). But (sorry Phil) it's a bad analogy. As I said above, a lot of very good skiers, including racers, are moving to somewhat softer boots as boot design and skiing style evolves. It's not just about sloppy and forgiving versus responsive and demanding. 

post #6 of 9

Boot flex is like suspension.  It's not just about ultimate flex, but also about progressive flex.  You have to find a balance that is soft enough to allow your ankle to flex enough for you to be in proper position, and you have to have it stiff enough to transmit forces where you want them without you having to move too far or taking too long.

 

There is a trade off between forgiveness and performance, but a racer at the ragged edge of DNF needs forgiveness just as much as a recreational skier who can decide to just forgetabout that turn (without needing to worry about missing a gate).

 

It also depends on speed.  A boot that is stiff enough to provide the correct response at high speed with the added input of the high centrepetal force of high g turns will be too stiff at slow speeds.  You decide what your compromise is going to be based on what type of skiing you do most often and what type of skiing is more important to you and how much so.

post #7 of 9
Quote:
Originally Posted by Ghost View Post

Boot flex is like suspension.  It's not just about ultimate flex, but also about progressive flex.  You have to find a balance that is soft enough to allow your ankle to flex enough for you to be in proper position, and you have to have it stiff enough to transmit forces where you want them without you having to move too far or taking too long.

There is a trade off between forgiveness and performance, but a racer at the ragged edge of DNF needs forgiveness just as much as a recreational skier who can decide to just forgetabout that turn (without needing to worry about missing a gate).

It also depends on speed.  A boot that is stiff enough to provide the correct response at high speed with the added input of the high centrepetal force of high g turns will be too stiff at slow speeds.  You decide what your compromise is going to be based on what type of skiing you do most often and what type of skiing is more important to you and how much so.

Brilliant
post #8 of 9

Beyond I think your right on with the industry guys getting people in a softer or should I say less stiff boot flex.Rossignol has the new frontside allspeed elite that looks awesome and has the ability to go from 130 to 110.It sells as a 130 and it would be easy to say it's a gimmick,it should be interesting to see if people review it and can tell if it really works.Of course because it is a Rossignol product I'm sure it will work better than any other of the manufactuers products!!

post #9 of 9

Just throwing out a question to you boot experts: Aren't there two types of boot stiffness to consider?  Yeah, a racer with tree trunks for legs needs a 140 or whatever flex, but what about the lateral stiffness of the boot? I now have two sets of boots that are basically plug boots with a relatively softer forward flex, which in some ways gives me the best of both worlds with the boots more versatile due to the relatively softer forward flexing (one set of boots is only around 110), but also giving solid performance when the ski is put on edge.

New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Ski Gear Discussion
EpicSki › The Barking Bear Forums › On the Snow (Skiing Forums) › Ski Gear Discussion › Right amount of boot forward flex/ are most skiers in too stiff boots?