Video and Thoughts on Risks of Locked Binding Toes

Our thoughts are based on the talk by a biomechanical engineer Jeff Campbell. You can watch the 25min video further below.

Bio-mechanical engineer Jeff Campbell presents findings from his study. You can watch his 25min talk below.

We are all guilty of locking out our tech toe pieces while skiing downhill. If you are thinking “not me” right now then you are probably lying or you landed on this website by a mistake.

My assumptions are that most skimo racers lock out their toes close to 100% of the time when skiing on race skis (in races and training), and over half of the time when skiing on their bigger/backcountry skis.

Personally, I usually unlock my toes on my bigger skis when conditions are “breakable” (crust, wind slabs…) and when skiing where coverage is thin or trees are tight because the risk of twisting a knee or simply falling are higher. I do the same on my race skis but less often.

One rationale for locking the toes is to prevent losing a ski that is without brakes. Occasionally, I use ski leashes to prevent loosing a ski but not often enough which then gives me a “bad” reason to have my toes locked. My main fall prevention method is skiing at speeds at which I feel in full control – my perception is that I am in control 80-90% of the time.

Some seasons I used ski brakes and after watching the talk below I think that is the best option to prevent loosing a ski while skiing with an unlocked toe.

Locking vs Unlocking while Skinning and Steep Skiing

By now, you have probably noticed I have been only talking about locking/unlocking the toe pieces while skiing downhill and that I haven’t mentioned skinning (tour mode) at all. This is because I don’t know anyone who skins with their toes unlocked even occasionally. However, the video below will point out situations when it would be advisable to do so.

Skiing steep terrain or when conditions are hard/icy are probably the only two situations when I believe locking out the toe is preferable. The risk of premature or unwanted release in such situations outweighs the other risks, in my opinion. Also, when you are skiing something steep or icy then you are skiing carefully anyways, therefore, already minimizing the chance of injuring yourself due to skiing and crashing at high speed.

Lower Leg Injury and Deep Avalanche Burial

Now, that I have pointed fingers (at all of us) and put my thoughts out there, go ahead and watch this highly recommended research talk.

Jeff Campbell – Retention and Release in the Backcountry:

What Are Your Habits and Thoughts ?

Scroll down to the comments section and share your habits and thoughts on this topic. It’s always interesting to learn what other people are doing.

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Comments

  1. 1. With the caveats that: a) the Nm torque results have to be combined with the boot sole length to be back-calculated into a release value number, b) both the release value charts and the testing device are designed for a lateral release at the toe, not the heel, and c) imputing a release value number to the toe only is probably even more suspect … the bottomline is that the LTR Auto “1.0″ has a release value number with the heel pins engaged (i.e., as in skiing) that ranges in testing from around 8.5 to 9.5, i.e., pretty typical for a race binding (despite all the claims that the toe is “locked” or somehow not ISMF-compliant). This also matches up with my ability to twist out of the toe.
    2. To adjust the toe lever position, first back out the very small Philips head screw a little bit, then that will allow you to turn the larger screw head.

  2. Stano I have already asked for a replacement lever, here in Greece, but is difficult to find it and in any case , not earlier than…..autumn. I have nearly two more months of spring skiing-my favorite- for this season, so i prefer to find another “solution” .

    Jonathan I red the numbers you posted http://www.skintrack.com/skimo-racing/gear-guide-first-skimo-racing-setup/ , but can you explain me which DIN number, is similar to 65Nm and 35 Nm release value of toe and heel piece of LTR 1.0 auto? Also I van see two screws at the side of toe lever, one bigger one – , and one smaller + . with which one should I “play”?

    Thank you both for your answers

  3. Greg, my quiver includes four pairs of the Dynafit LTR “1.0″ “Auto” version: I can twist out of them, and I’m not particularly big or strong.
    Plus I’ve even quantitatively tested them with a binding torque tester device.
    The toe lever is spring-loaded, but so are race bindings from Plum and ATK.
    The 1.0 toe lever also has two different positions. If you find that upon binding entry the toe lever is popping up too much so that it truly is locked in place, then play around with the little screw adjustment on the side of the lever to fine-tune it so that it comes to rest in a slightly less vertical position.

  4. Hi Greg. Yes, it’s not about ISMF compliance but about injury risk. I have skied (and thousands of others as well) on locked out toes for many years, whether on race bindings or other, and haven’t had an injury like presented in the research in the video. However, I have also skied plenty with a climbing helmet and not a ski helmet, I have always wore my seat-belt and never had to be saved by it, etc… My point is that I would recommend anyone to ski with unlocked toes unless that risk is outweighed by something else – like a premature binding release on a steep slope.
    You should be able to solve your new setup by simply changing the toe pieces. I know, it’s extra money but most likely worthwhile in the long run.

  5. Hi, so nobody ski on race bindings with auto lock feature? I have very recently “upgrade” to nagna prabat with low tech race 1auto, and after watching this video and your conversation, I wonder if I made a bad purchase. I really don’t care if ltr are ismf compliance, but if I have really increased dramatically injury probabilities skiing on them, compared with my previous radical st….

  6. Yes, when skiing about a rappel or on a steep enough line where a slide would not be stopped until the bottom. Otherwise I ski resort, powder, and mellower ski mountaineering with toes unlocked.

  7. Howie, thank you very much for sharing your personal experience. That must have been one hell of an event to live through. I am glad you are back and skiing strong again!

  8. Howie Bock says:

    I learned the hard way. I was in an slide while skinning uphill with the toes in lock mode. An avy air bag was no help for a ski that wouldn’t release so under I went and under I stayed. Fortunately it was in the alpine with few obstacles to get filtered through. Unfortunately one ski wanted to go west and the other east. My groin was strained to the max and something really serious was about to happen when the slide stopped. The ski broke but the binding stayed on. I was lucky that I could walk away. I never lock my toes and recommend to my partners not to either.

  9. I use leashes when I’m in true ski mountaineering terrain at or above treeline.
    (Typically that would be the Presidentials Range in NH, and assorted volcanoes in Oregon & Washington in June, July, and sometimes August.)
    I’ve locked my toes for only one descent in a race.
    (Second lap in a ~5,000′ vertical race when I was pretty much tied for third at the final transition, and the podium medals would be handed out by a skier who had previously come in 4th at a race on that same mountain … in 1942, and then went on to fly bombers during WW II, so worth the risk to be congratulated by him!)
    And now to anticipate your second line of inquiry, for Dynafit/Tech binding cumulative use, I’m at nearly 4.4 million earned vertical. (Feet, not meters, remember, I’m American!) My release history is as follows:
    - Messing around in the woods on the periphery of a resort trail, ski (and boot, even saw the bark mark on the boot tongue) got caught under a small horizontal log just barely hidden under the snow.
    - Descending through treeline, ski tip hooked on a small shrubby branch (just like hooking a tip in a slalom race course).
    - Returning back through the resort, in a bumped-up glade with a couple feet of fresh snow in the troughs, got too far forward and tips got buried before hitting a bump, started going over the handlebars and binding released. (Although technically the binding released without my falling, I don’t think this counts as a prelease since it’s probably a good thing the binding released.)
    - At a resort closed midweek in the spring, skiing way too fast (the perfect corn was just too hard to resist!), hit a compression and binding prereleased just like it sometimes did in similar situations in GS race courses.
    All of these were with regular Dynafit bindings years ago, not with race bindings. But I suspect that’s just coincidence, as both the releases and prereleases would probably happen again if I weren’t careful.

  10. Jonathan, so do you always use ski leashes or brakes then? Do you unlock your toes in races?

  11. I lock my toes usually only once a twice a year. Typical both crevasses and fumaroles are involved. Like when you traverse back on Hood from the Hogsback to the skier’s left. Otherwise, toes are left in ski mode when skiing. I don’t have any regular touring partners who regularly ski with their toes locked. And if I did, well, they’d no longer be my touring partners — I don’t want a simple fall to become a long difficult extrication. Yes, ski binding release functions aren’t perfect (whether alpine downhill or alpine touring), but a toe lever in tour mode is entirely eliminating any hope of lateral release.

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