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Where I live, winter is still a good bit away, but last year I slipped on ice and ended up with a black eye and a broken wrist. This year I sincerely want to reduce the chances of that recurring.

I am wondering what common materials you can use to increase the co-efficient of friction between the soles of your shoes and the ice.

Sure, you can wear heavy iceboots with ridges, but then it's a hassle having to put them on and off when entering the house, especially the serious mountain type ones.

Two questions that users in cold climates might be able to answer to save myself trouble this winter,

  • Are rubber soles the best alternative to heavy boots, or has anyone found another material that maximises friction with the ice?

  • Is there a walking style that minimises your chances of a fall?

Penguins (and some other winter hardened birds) seem to have the ability to keep their balance, although in the penguins case, possibly at a cost of the most undignified walking/waddling in the animal kingdom.

On TV, you do see them slip occasionally , but they seem to manage ok with a high center of gravity, unless they deliberately want to slide on their stomachs.

migrated from physics.stackexchange.com Aug 3 '15 at 13:47

This question came from our site for active researchers, academics and students of physics.

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    Maybe sliding on one's stomach is the superior mode of transportation, then. – Jonas Aug 3 '15 at 13:06
  • Some skeleton racers are likely to agree with that. – WBT Aug 3 '15 at 13:11
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    Not what you're asking for, but if you are really concerned you could also look in to lessons in how to fall at your local martial arts school ( I think it's called breakfalling in english). Though it takes time to actually build it into your natural reaction. – Deruijter Aug 3 '15 at 15:14
  • @Deruijter whatever it takes to stop smashing up bits of myself by falling on solid ice is fine by me, a month trying to write left handed (when I'm naturally right handed) is enough, thanks for that. – CountTo10 Aug 3 '15 at 15:43
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    various models of micro spikes will give you superior friction. Usually they are worn on the sole of a shoe, and supposed to be easy to put on and off. Walking poles can also give you some extra balance. More generally, try to see the ice before you step on it, and use smaller steps, avoiding to push with your toes. – njzk2 Aug 3 '15 at 19:06

15 Answers 15

16

Yaktrax advertises products intended to help with this, which might be less damaging to interior surfaces than crampons. You can find some SE discussion on those kinds of products here.

Keeping a low center of gravity can reduce probability of injury by reducing how far you fall. Positioning yourself so that if you do fall, a softer part of your body (like your rear end as opposed to wrist or eye) hits the ground first can also help cushion the fall and reduce the chance of injury.

You can also visually scan the ground for areas that might be rougher (not reflect light as smoothly) or have packed snow instead of ice. In urban environments, walking along packed snow next to a sidewalk may be safer than walking on an icy sidewalk. When things start to melt, watch out for and try to avoid places where there's a thin layer of water on top of smooth ice; the fluid can act as a lubricant and reduce friction.

In particularly slippery conditions, especially downhill, you can "walk" with your rear low to the ground and your arms down with palms out just above the ground, and your eyes scanning for rougher areas and/or things you can grab onto if you fall / start sliding.

  • Thanks for the quick answer, we don't often get heavy snow or ice where I live, but when we do, we panic, basically, compared to say, Canada. – Acid Jazz Aug 3 '15 at 12:59
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    I'm from Canada. I wear my Yaktrax even when it isn't that icy, not because I'm affraid of slipping and falling, but because the added tracking permits you to walk faster on the hard snowpacked trails (your foot doesn't slip out behind you with each step). – ShemSeger Aug 3 '15 at 16:04
  • The Yaktrax are amazing, and easy to put on and take off. The blacktop in our neighborhood got a thin solid sheet of ice on it. Very hard to walk across. With the yaktrex, I can do football moves, and have complete confidence in my stability. Love them! – Dustin Graham Aug 3 '15 at 19:37
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    Yaktrax totally suck. Microspikes are way better. As far as I can tell, the only situation where yaktrax might be better than microspikes is if you're going running in the winter. – Ben Crowell Aug 4 '15 at 20:36
  • Comments on Yaktrax' effectiveness or lack thereof are better directed here. – WBT Aug 4 '15 at 20:38
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Here at south Russia, we have lots of ice surfaces every winter and need to walk around. So, practical experience:

  • The simplest option to reduce slipping will be to just glue some hard waterproof low-grit (approx 60-120 grit) sanding paper on the bottom of your shoes. This is often used here amongst aging people that are less agile due to their age. If they use this trick from year to year - I assume it works:)
  • The penguin-way to walk (particularly, small careful steps) will help you too.
  • When you are just starting to fall, quickly squat. It helps to retain balance and even if you fall, the damage will be significantly less. Train this movement beforehand and put it to reflexes; it's hard to remember and do this trick when you're already falling.
  • Prefer to walk close to walls, handrails, trees, bushes - any object that you can quickly catch with your hands. Especially on stairs, always keep your hand on the handrail!
  • Prefer to keep your steps away from car roads when ice is around; it is hard to drive in such weather and very, very hard to stop the car quickly.
  • Take a few lessons of ice-skating, it will teach your body how to balance on ice and how to fall properly.

Hope I didn't miss anything important. Happy winter! ;)

P.S. Regarding rubber soles, this depends highly on which sort of rubber. The softer - the better. And some sorts of rubber become more stiff and slippery at low temperature. And beware, there is some plastics that look very similar to rubber, but are slippery as hell. Having it on my feet was unpleasant surprise for me a couple of times. Re: Mountain-purposed boots with heavy sole are no good for glass-flat ice. They work well on snow and neve, due to hard, well-developed bottom surface, but easily slip on pure ice. I've tested.

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This actually happens to be pretty relevant to Physics(so it's kind of odd it was migrated away from the Physics.SE).

You were actually on the right track with the penguin idea and increasing your co-efficient of friction. The graphic in this article has been floating around the internet for a while now. It's pretty self-explanatory, but the gist of it is to keep your center of gravity above the leg that is currently supporting you. The intent is that your weight is then acting perpendicular to the icy/slippery surface. But, instead of increasing your co-efficient of friction, you reduce the force acting upon that friction.

I am not a physicist, but it boils down to static friction. The important part is that there is some horizontal force(along the surface) which will cause the sole of your shoe to 'break' the static friction and cause a slip/fall. Of course there are other ways to fall, but this is the most relevant one.

Taking the graphic in the above article: when you walk normally on a normal surface, you are exerting a force along the surface, but it happens to be smaller than the static friction between your sole and the surface. So you don't slip.

On a slippery surface like ice, however, the amount of force necessary to break that friction is much smaller. The more slippery the ice, the less force is needed to break the static friction.

So that covers your second bullet. As per your first bullet, I can say as a native northerner in the US, I never saw a real need to wear special shoes on icy conditions. My only recommendation is to wear something you're comfortable in. Wearing boots for the sake of ice means you have to learn how to walk in boots plus learn how to walk on ice - it just needlessly complicates things and you're probably more likely to fall.

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Are rubber soles the best alternative to heavy boots, or has anyone found another material that maximises friction with the ice?

Rubber soles will have zero effect on ice. You need something that will dig into the ice to stop you slipping, rubber suffers from the same issues as any other material, it simply cannot get enough traction on the ice.

Is there a walking style that minimises your chances of a fall?

In my experience, no, The only reliable way to not slip on ice is to use something with spikes (yaktrax, crampons, football boots, running spikes...). I've fallen when being extremly careful and when I've been moving fast. Ice has a way of catching you out. This is why all mountaineers use crampons above the snowline. It's the only reliable way to gain traction.

It also depends on what type of ice it is, how warm the air is, how cold the ground is, etc.


Penguins can and do fall over

enter image description here

They have special ridges on their feet to aid with traction, they also spend a lot of time sliding on their bellies over icy ground.

  • Thanks, my local health and safety website has advice, well meaning I am sure, but a little bit quaint. Just saw the penguins now, I know how one of them feels. – CountTo10 Aug 3 '15 at 14:18
  • I think @WBT is the answer you need, get some yaktrax (other brands are available) they're cheap, easy to use and they work. I was simply filling in some of the missing details. :) – user2766 Aug 3 '15 at 14:23
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There's a lot that you can do in regards to walking style:

  1. Avoid walking on the ice if you can. (if it's a poorly cleared sidewalk, and there's snow on grass near it, walk in the snow)
  2. If it's a layer of ice over a base of snow, crack the ice by walking heel first (and really put your weight into it), so that you create footprints in the snow rather than trying to walk on top of the whole mess.
  3. If you must walk on the ice, you'll need to take slow, deliberate steps:
    • Slowly place your foot down flat on the surface (not heel first or toe first) to increase the contact surface while keeping your weight on your back foot.
    • Shift your weight onto your forward foot.
    • Bring your rear foot forward, and repeat.

Note that #3 is very, very slow. It'll take a few steps to figure out what a safe speed is to travel at, but you also have to be wary about changing conditions (for example, if you're moving out of shadows onto a sunny patch (for example, as you approach an intersection in a large city), it might have a thin sheen of water and be much more slippery).

I'm assuming you're wearing normal footwear for this. If you're in a hard plastic boot like a ski boot, which has little to no traction on the bottom, approach #2 is often better for packed snow than #3. If you're expecting to do a lot of walking in ski boots in icy conditions when you can't put back on your skis (e.g., dealing with stairs), something like Seirus' "Cat Tracks" are quite useful:

enter image description here

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    No 2 is called post holing. Post holing is extremely tiring if your doing it for any length of time. Most mountaineers avoid this where possible. It's much, much, much less tiring to use crampons on top of the snow than to post hole though it. I've been forced to post hole for hours before now, it's exhausting and very slow. – user2766 Aug 4 '15 at 14:29
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    @Liam : thanks, didn't know there was a name for it. I'm not advocating it for hours or miles (if you're planning on that sort of a trek, you need crampons or snowshoes or other winter footwear) -- if you have to go a few blocks to the store to resupply or similar, and you don't have the proper gear, it's safer than walking on icy sidewalks. – Joe Aug 4 '15 at 14:37
  • Postholing is when you sink in much deeper- knee to waist depth- and although that is extremely tiring, I think what @Joe is suggesting in #2 is just a small amount of depth that might not even exceed the sole of a shoe, just enough to get some traction and leave a footprint, possible if the surface you're walking on is easily enough cracked by the weight (which is not always the case). The original question seems motivated by settings where there's generally not enough depth of snow for postholing to be an issue. (See hiking.about.com/od/Hiking-Glossary/g/What-Is-Postholing.htm) – WBT Aug 5 '15 at 12:46
  • @WBT : I was thinking maybe ankle to lower thigh-deep snow at most ... basically as you said, to force some traction when you've got a few inches of snow covered by a glazing of ice. Above the knee or crotch deep snow would be miserable that way. If you're going out camping, I'd expect you to be prepared. The most I've ever been 'surprised' by snow was about 12-18" in Kentucky in 1998 that fell in only a few hours. (they weren't expecting nearly that much, and the locals didn't know how to handle it ... motorists ended up getting stuck overnight on I-75 because of the lack of plows) – Joe Aug 5 '15 at 13:32
  • Oh, wow. Lower thigh is very deep, and even ankle deep is uncomfortable and necessary to stop from slipping on ice. Generally, a little bit of crunch in the step should be enough to do the trick. Also, keeping a sleeping bag and some "emergency" supplies in one's car during winter is a good idea in case of surprises like the one you mentioned. – WBT Aug 5 '15 at 14:56
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If your aim is just to avoid falling, do as WBT suggests and get some ice-grips. These can be put on and removed in seconds and can be carried in a small bag or even a pocket. But if you get UK-type weather, in which ice is often patchy, avoid grips that use what look like steel springs. These are easily broken on hard surfaces like pavement. Better to get grips with small studs. These used to be expensive but no more; I bought several pairs of perfectly adequate grips in a well-known UK retailer for, yes, £1 a pair.

  • Studs are a good idea, we even put studs on horses in bad weather in the UK, nice answer :) – Aravona Aug 4 '15 at 12:40
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So far, no one has stated the obvious: Don't step on ice! Walk on snow, bare pavement, rough ground, lawns, flowerbeds, or whatever alternatives there might be.

enter image description here

When stepping on ice is unavoidable, here are some observations which can make slipping less likely:

  • Ice is most slippery when it is at freezing temperatures (32 °F/ 0 °C). When it is colder, it is less slippery. For footstep purposes, ice temperatures below about 24 °F / -4 °C behaves much like smooth finished concrete.
  • Continuing with temperature, if the bottom of your footwear is warm—as when initially stepping out of a warm auto or building—it will melt the top surface of the ice and make it slippery. This is the time to move very cautiously and with very small steps.
  • As your footwear cools, it loses the capacity to melt the ice surface. If it is able to go below freezing, good traction will occur. Maybe as good as walking a similarly textured surface (to the ice) like glass or marble tile.
  • Insulating your feet from the bottom of your shoe will keep you warmer and the shoe sole colder. Those are both good reasons to wear layers of socks or choose footwear which has insulation below the foot.

In summary:

  • Wear good footwear
  • Give your shoe 10–20 seconds to chill before walking normally.
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    Actually very relevant, applies to non-snow conditions too. For some reason people seem to seek out grass on steep slopes, this is almost always more slippery than good clean rock. – user2766 Nov 16 '16 at 15:01
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My best solution for this is to wear a pair of flexible running shoes with spikes. The spikes are at the front; walk towards your toes to make sure the spikes dig in. Team them with warm socks for insulation (and remember a half-size larger than your normal shoes for comfort!) You can also get undersoles with spikes for ordinary shoes. Like as not, someone will make galoshes with spikes to slip over shoes, which should be waterproof. Anti-slip safety boots will give some traction on some types of ice, but not on all. They're good on snow, though; walk on the virgin snow wherever possible, and stay off slopes if you can.

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I've been attending school in the Upper Peninsula of Michigan, USA. We get ridiculous amounts of snow (for the US anyway) and ice. Generally, when I slip on the ice, my feet slide out from under me to my front, and I land on my behind. To counter this, I've learned to walk with shorter steps, keeping most of my weight on the balls of my feet as opposed to further back.

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Approaching this from a physics standpoint, the primary reason people slip on ice is due to low friction. I personally think this is not the case, but rather, the low friction is the gunpowder to the bullet that is sliding, but the trigger is not the low friction. The real trigger (in my opinion of course) is force. It is impossible to move without force, and that is true on ice. When we walk on any surface, we rely on friction heavily to keep our feet in place as we move the other foot forward. Ice has little friction, but we still rely on it, so our foot slides. Ice spikes remove the need for friction, by digging into the ice, and using the ice to hold it in place. It's like hammering a nail into the wall, the wall prevents the nail from moving with the rest of the wall. To slip on ice with ice spikes, you have to move all of the ice for the spike to move. Without spikes, its just your foot. So, the trick is to remove that need for friction without ice spikes. The reason we need friction wile walking is, based on experience, because when we walk, we exert sideways force, and a lot of it, on our feet. Friction overcomes this force, but on ice, there is not enough friction, so the trick is to walk without sideways force. It's not an easy idea, but it will greatly help. For ideas on how this might look, think of marching. The foot needs to land on the ground from directly above it, and you need to to have most of your weight already on it.

This is the same principle behind the tiny steps people take on ice. They take steps shorter than their own foot length, and all their weight is vertical for each step. It needs to be the same direction as gravity. Drop anything, and it falls straight down, that needs to be your foot. This will remove the necessity of friction in your walking, which is the key, when you have less friction, you need to use less.

If you don't believe me,or want to practice, pay attention to your back foot next time you walk. Feel the force on the ball of your foot. Feel your leg pushing you forward, a non vertical force. Or try running, and really feel the your feet wanting to slide in your shoes. Realize how much you rely on that massive amount of friction on surfaces. Perhaps wear socks as you walk on hardwood or other kitchen surfaces, feel your feet slide, and take them off to feel how your bare feet resist moving in the same conditions your socks slid on. If the force is not completely vertical against gravity, friction is what is needed as a counter for stability. After all, its not nearly as hard to stand on ice.

Lastly, of course this only really works if the ice is not mostly flat. Gravity will apply sideways forces for you due to how it works on non flat surfaces. This is why round objects and liquids go to the lowest points they can get to. Uneven surfaces provide gravity with a way to change its pure vertical pull into sideways force.

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Emergency Method of Walking a Short Distance on Ice Without Slipping:

If you find yourself on ice unexpectedly and you don't have far to go, an emergency option is to remove your shoes/boots entirely and walk in your stocking feet. This is obviously not a good idea if you're not going to be indoors within a couple of minutes, but if you're just walking from the car to your house, it works quite well.

The idea is that your body heat can pass through the socks, melting the top layer of ice. Your socks absorb this melted ice, but immediately refreeze, which means that your sock is now glued to the ice. The adhesive properties aren't strong enough to keep you from moving, so you can simply take another step, your sock sticks to the ice again, and so on.

Low Cost, DIY Solution:

A more long-term solution is to get an old pair of boots with thick soles, preferably with the treads still more or less intact. Buy some short wood screws with rounded heads and screw them into the soles of the boots. Obviously, you have to make sure that the scres aren't so long that they go all the way through the sole and into your feet. Arrange the screws in a grid pattern, with maybe an inch or an inch and a half between them.

If the boots are the slip-on/slip-off variety, you can easily put them on and take them off when entering and leaving buildings. Be careful not to wear them on wood or tile floors, because the screws will damage hard surfaces.

This is basically the way old fashioned hobnail boots worked, and it still works today. All together, the materials shouldn't cost more than a few dollars, and if you already have an old pair of boots, the cost will be no more than a dollar or two.

The Best Way to Walk on Ice:

You will slip less if you don't lift your feet at all. Pretend you're ice skating, and slide instead of walking. The reason this works is that you are keeping the largest possible surface area of your feet in contact with the ice, which provides the maximum amount of friction. Since ice and friction don't like each other, this technique isn't foolproof, but in the absence of any better options, it is the best you can do.

The next best option is, as previous answers have already said, to take baby steps. The shorter your stride, the less momentum you have, and it is less likely that you will go ass over elbows. Move as slowly as you can, and keep your feet close together.

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I find that with icy conditions that you need to change a few things about how you're walking. I used to run on icy trails and snowy conditions and found a few things that helped me not take a spill.

Be deliberate with your steps AKA pay attention to what you're doing. I tend to walk more with my head slightly focused down to see where my foot placement is going.

Shorten your stride and be sure to be ready to shift with your feet. Stronger ankles really help here since you could end up sliding all around.

I avoid ice where I can and try to walk on unpacked snow. Once snow gets packed enough, it becomes just like ice and you slide about.

Pick up some additional grip on your shoes. Others have mentioned products like Yaktrax all through DIY screws in your boots. Find something that works for you though. I haven't tried but heard good things about Salomon trail shoes. Some of them have little spikes that help gain traction. That or the Yaktrax would be good so you can use them year round.

For shoes, I found I have better traction and grip with a flexible sole. I usually use Nike Free running shoes which have little blocks of traction instead of one cohesive sole. I find they flex pretty well and grip things well. Plus, they tend to get stones stuck in them so I'd like to believe that helps with some traction.

Lastly, when it really comes down to just slick, slick ice... I mock skate across it. I just "skate" my feet along until I am more comfortable getting full grip. I cut my stride down to maybe 1/3 of my normal stride, too.

Even with all the precautions you can think of, taking a spill is almost inevitable for most things so you really should be preparing for that. I know when I am hunting in snow covered and hilly woods, I will most likely fall from something. Try to always keep it in your mind how you will fall and which parts of your body are more likely able to take the abuse.

Instincts tend to tell you to put your arms out to catch yourself, but the bones in your arms/hands are smaller and not as willing to take abuse. So, I might fight that and take the fall on my hip, shoulder, or somewhere that I can spread the impact out over a larger area. I may get a good bruise, but the odds of me landing on my fingers or wrist and breaking them are lower.

These are just my personal experiences from my life in Ohio. From the flatlands in the North to the hills of the South, I have taken a few spills here and there and kept trying to learn from it.

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Wear socks over your shoes (as well as your usual socks inside your shoes, of course). This is a fairly well-established technique (see e.g. here or here), and its effectiveness has been scientifically demonstrated by Parkin et al. (2009).

References

"Preventing Winter Falls: a randomised controlled trial of a novel intervention"; Parkin L, Williams SM, Priest P; NZ Med J. 2009 Jul3;122(1298):31-8

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rubber over-shoes are a frequent answer for this. When I first moved to a climate with a lot more snow than where I grew up I found that they helped a lot.

However to really combat slush and dirt I've moved to using boots. Yeah they do have the downsides of time to take on and off, that is true.

1

Not a real answer to your question, but maybe it helps. In Holland we use a lot of salt during the winter to lower the melting point of the snow/ice (as a result, we have an abundant salt water vegetation along highways even far inland). This may be a good solution around your home? When not meant for consumption, salt is very inexpensive (we pay like $2 for 25 kg).

In case of snow, walk on the fresh snow and not on the parts that other boots/vehicles have turned into ice.

  • 1
    When you deliberate whether to use salt, please keep in mind that it is bad for most of the non-saltwater-plants. Therefore it is forbidden to use salt on private property in many cities in Germany (there are exceptions for stairs and ramps, check your local regulations). Germans use sand or small stones instead. – Sumyrda Nov 17 '16 at 14:53

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