In 1988, the Atomic Ski Company engineer Rupert Huber was asked to make a powder ski that could float on top of fluffy snow better than the average ski. At the time Atomic had gotten into snowboard production and the engineer decided cutting a snowboard in half and tinkering around with the edges could do the trick. Thus, the world’s first superfat powder ski, the Atomic Powder Plus, was created.
Decades later fat skis are still a top choice for ski enthusiasts on powder days, but what happens when the infatuation with fat skis becomes your daily driver? Dr. Kim Hewson, a professional in the industry refers to this as ‘Fat Ski Syndrome,’ and the doctor turned ski instructor has spent a good amount of his second career educating the general and professional ski public about the dangers of misusing fat skis.
While Hewson deems himself a “Ski Nerd,” the 88-year-old has a rich history of understanding the body and how it works when engaged in sports more specifically on snow. A lead instructor and staff trainer at Telluride Ski and Snowboard School, he spent the majority of his career as an orthopedic surgeon, a career that spanned a wide range of disciplines from Director of Sports Medicine at the University of Arizona to a part-time consultant to the U.S. Ski Team before learning to ski at the ripe age of 30.
Fat skis are still a top choice for ski enthusiasts on powder days, but what happens when the infatuation with fat skis becomes your daily driver?
A good base of the skills that Dr. Hewson has brought to the ski school revolve around dynamic and scientific data that can assist in body alignment and movement reducing the risk of injury. Known as biomechanics this science-based method puts an emphasis based around anatomy with skiing – think skeletal alignment and efficiency methods that allow muscles to do less work than needed helping to lead to optimal performance. It was in using and teaching these techniques of instruction that Hewson stumbled across the idea of fat skis being used ineffectively. Thus, this idea of ‘Fat Ski Syndrome,’ a concept around how using fat skis in the wrong snow and terrain setting can be detrimental to one’s legs evolved in 2014.
“I was finding that some of the instructors were going for powder runs in the morning then having afternoon lessons on blue runs and complaining of knee pains,” says Hewson. It took him nearly a year of playing investigator to find the culprit—fat skis. He was noticing bilateral medial knee pain amongst skiers using fat skis on groomed or firm terrain and the reasoning came down to the fact that they were using the skis inappropriately.
Hewson explains how fat skis were designed for flotation in powder and how when put on groomed or hard pack terrain it requires an action of tipping the foot that puts a powerful strain on the knee causing tendonitis or bursitis which when continued for long periods of time can have chronic effects.
Looking at the issue from afar the argument seems to make sense, however some in the industry may see it a bit differently than Hewson, like shop bum and gear tester, Jason Layh. Layh has spent over a decade at Alpenglow Sports in Tahoe City, California, and has been testing ski and backcountry gear for nearly two decades.
“It seems a bit harsh,” says Layh on the singling out of powder skis, “powder skis are very different than when they first came out,” says Layh as he mentions how some modern-day powder skis are built tip to toe with rocker making them easier to turn. While he sees the connection and agrees that continually skiing on fat skis in the wrong conditions can have detrimental effects on the body, he sees that in skiing as a whole. “In skiing we are moving fast and impacting our body in many ways,” says Layh, “too much of anything can be a challenge, it is all about finding a happy medium.”
Layh sees many factors that can play role in lower extremity issues aside from using fat skis in hard pack or on groomers, he says certain changes like improving a skier’s setup through foot beds and canting – a process of adjusting and tilting the foot in the boot to help set it to a neutral position can make a big difference. However, Layh sees the biggest challenge with ski selection at a socioeconomic level. “Skiing is continuing to get more expensive,” he says, “for weekend warriors what the purpose of having more than one set up…most people are buying skis with the ideal conditions in mind and aren’t putting that many ski days in throughout the season.”
Unfortunately for the skier ideal conditions are not always present and ski prices are not exactly ideal on top of that. According to the National Ski Areas Association (NSAA) in the past two seasons the average season pass holder skis 7 to 9.8 days throughout the winter and spring. On top of that prices of new skis can range from around $400 to upwards of $1000 which often doesn’t even include the bindings. The categorization of ski style type can change pricing and also vary amongst the different types of brands.
To get a general idea ski width is a measurement taken underfoot at the waist of the ski. Race and GS Skis tend to be thin at 60mm-70mm. From there they move up a little wider for beginner and intermediate skis, to a little wider for groomers all the way up to All-Mountain type skis at 90mm-108mm, and powder skis usually ranging from about 105 on up to 130mm—sometimes even wider. Hewson is wary of skiers who only use skis wider than 100 mm underfoot.
As much as one could look into the anatomy and kinesiologic nature of skiing what it really comes down to is having a quiver of skis that are appropriate for the right conditions. Practicality also must be taken into consideration.
Taking a lesson from Hewson’s page, “use them where they work,” he says.
Photo: Unsplash
I think the fact that people were teaching classes on them speaks more to them being used outside the context they intended than just general skiing on hardpack. I do think he is on to something however this seems like more of a starting point of a hypothesis. Also consider we are all biomechanically different at one level or another, people who are taller with longer legs might have less of an issue with wider skis, than a person of a shorter stature.
I’m glad to see somebody is writing about fat ski syndrome. I live in Utah and we have had 7 weeks of no new snow so we are skiing on hard, mostly man made snow, and the dominate ski in the lift line is a fat ski! I’m guessing 90-110 cm average. When I think about the percentage of powder days verses groomer days, I am amazed that the ski of choice is a fat ski!
Coming from a ski racing background you know there are good reasons for using the right tool for the job. Besides rocker and width, a fat ski is slow from edge to edge. It takes longer to go from one turning edge to the other turning edge which allows for a smear turn in powder and reduces the ski from wanting to carve. Powder is three dimensional and acts more like water so you don’t want to carve like you might on a groomer or hard snow. A fat ski also requires more angulation on hard snow to put it on edge which may cause knee pain. I am watching skiers with fat skis on groomers slide a lot from edge to edge.
A narrow ski is quicker from edge to edge which reduces the slide on groomers and is much easier to get the ski on edge and carve. The narrower ski allows the skier, if applied correctly, to have more pressure on the inside edge and hold on hard snow or ice. A fat ski, because of it’s width, has more leverage on the body and makes it much harder to hold an edge on hard snow. It isn’t built to hold on hard snow!
Bottom line, there is no one perfect ski for all conditions. Either we need at least two pair of skis in our quiver or we find a ski that isn’t the best in all conditions but is good enough. Think about your average year and average snow days where you ski. I bet you would find a narrower ski should be the tool for the job.
Thank you
I Run 80 underfoot and always have a
Good day ⛷️
I wouldn’t even consider 90-110mm underfoot to be “fat”. That’s pretty squarely in the “mid-fat/all mountain” category in my opinion. My last two daily drivers (for the last 5 seasons) have been 114mm and 117mm and I’ve never had issues with knee pain or being able to hold an edge. Haha my skinny skis are 96’s! And those will hold an edge on anything and happily rail GS turns all day. Some people like to ride slacked out enduro bikes and some people like to ride XC bikes. Both bikes can ride the same trails but the experience will be quite different on each. In my humble opinion there is no right or wrong answer. If you’re a newschool skier in the west I say ride em as fat as you like and have fun. If you’re a former racer kid or an ice coast skier go narrower. To each their own
There have been similar stories written up here by highly esteemed ski instructors. I think part of the reason instructors developed knee problems was that they tried to ski fat skis like carving skis and, well, you don’t. They were made for smearing turns and even ‘straightlining’ – you want to ski fast on fat skis, point ’em down and let the tip and wide waist disperse the energy, just like a dual suspension mountain bike. A light touch actually works best, in my experience. Things have changed a lot since 2014; waists have gone down considerably; there are very few 120mm plus made any more. Ski designers focus on rocker, edge taper, (how and where the ‘sidecut’ begins), and ski weight. Here’s another somewhat counterintuitive thing: skiing on narrower waisted skis with minimal to moderate sidecut (as opposed to ‘carving’ or ‘frontside’ skis) is more fun in deep powder for advanced skiers. You’re ‘inside’ the snow, more (if that’s your jam). There are skis in the 86mm to 94mm range that totally rip in all conditions. Huber developed the Powder Plus (which was HUGE) so that heli-skiers of modest talent (but fat of wallet) could skim on top of the snow, much like (weirdly) you would in a resort.
Hardly news, this had to be obvious to anyone who skied fat skis on hard pack ever since that Powder Plus came out. What is odd is how many skiers in NorthAm will rent!! or buy fat skis to only stay on groomers for a week. Fat skis are luckily still more of an exception than norm elsewhere when it comes to resort skiing and the far more appropriate 60-90mm range is what the average Joe is skiing on.
Problem is people don’t really know how to ski. Anything 100 cm or more in powder days are merely training wheels for bad toaverage skiers. Anyone who actually knows how to ski can easily ski even the deepest powder on a ski 90-100 cm underfoot. I started skiing in the late 70s when skis were long and straight. I spent 7 years in Utah from 2005-2012 and averaged 15-20 10″+ days a season. My go to ski during most of that time was a pair of 2007 K2 Seth Vicious at 179 in length with measurements of 139-98-118 and I coukd ski on even the deepest of days @ Alta or Snowbird with anyone on the mountain. Now that I live back in Chicago and ski everywhere from the east coast to the Rockies, my daily rider is a pair of 2018 Nordica Enforcers 93s at 185 in length. I’ve used these on groomers during a drought, on a few occasions with more than a foot of freshies and every xondition in between and have had no problems with my skiing or my knees. Why? Because I know how to ski. Real skiers do fine without super fat skis on any conditions.
I am with you on this. I have never skied on fat skies and never will. My skies are an all mt. ski. Quick turning and and so responsive. Your right, real skiers can ski any ski. Feel the edge and let them do the rest.
62 from the Mountain West. If you cant ride Volk Renn Tigers or Fischer C4’s thru a foot of fresh…stay home and leave it to us. Fat ski’s are for those who cant actually ski. Its called sledding.
EZ-BRO
I have been using the head collective 105 as my east coast daily driver. My narrowest ski is the head kore 93, but I much prefer the 105s. Everyone seems to think that fat skis don’t ski hard, but I can rip a deeper carve than anyone on the mountain. The best skiers ski big twigs.
I have been casually watching this over the years, and talking about it within my very random circle of ski folk, none of whom can afford quivers built from paying retail, all of whom have fairly hefty quivers. My purely anecdotal take is that the top of the bell curve for widely usable skis goes from 75 to 95. Beyond that range, even though totally usable in more than just optimalbconditions, the skis get very focused cery quickly. Anything over 105, especially with all the rocker and taper, is basically only for deep days, and under 75 is for day 28 of a drought when only hardpan and groomers are skiable.
The funniest thing to me is why someone who isn’t wearing your skis even cares what size underfoot you are skiing.
My dailies for 4yrs now are 150-122-141 rockered bamboo Liberty’s, before that 140-115-130 non-rockered Dynastars with metal.
I’m turning 48yo soon, have been skiing since 1984, am not tall (5’8) and ski 184/185cm.
I have skied all types/lengths/widths of skis and love skiing fatties daily. No body problems, love the extra challenge of tipping them to hustle carves, love especially how they’ll behave in any amounts of soft snow. So much fun and the fatties will blaze.
Again, I don’t understand why people who like skinnier skis even care lol. If you have good deep snow technique, know how to crunch the snow below, know how to submarine them…imagine…how much more effective you’ll be at creating your own platforms with 122mm underfoot lol. Sure, they are more challenging I suppose to carve ski on hard pack, but isn’t that another way of telling people around you who knows what’s up? And whenever did carving a ski on hard pack become ‘hard’? Especially in this day and age of shaped (ie I will turn for you) skis?
Guess you missed your call as a snowboarder, Lmao
Also recently a guy with fat skis going 50mph out of control on hard pack hit a tree and died. If you don’t want professional advice, Knock yourself out !
Didn’t realize the only real skier in the country is a flatlander tourist from Chicago who couldn’t make as local in the mountains and had to go back home and get a real job
After many years on 100+mm underfoot “quiver killers”, and a few years of drought conditions in my home range (Tahoe), I bought a 78mm setup, and have been working to learn how to tip and carve, instead of just sliding around. It’s been a revelation, and not just on the groomers. We finally had our first powder day this week, and I skied my 102mm setup for the first time, and it felt different in an entirely positive way.
In my off season training (that is, watching YouTube videos), I see that many of the very effective coaches are skiing <80 in all conditions (Deb Armstrong and Harold Harb, in particular). They understand this problem.
Interesting and spot on, glad I’m not crazy!
Tele skier here, bought a pair of fatties maybe 10 years ago, used them a handful of time where it was’t soft and deep, invariably, by days end, my knees would be screaming at me.
I understand biomechanics enough to connect the dots, and don’t use them for groomer days, ever, now.
My recent years at J Hole has seen the ski shop only offer up 108+ “that’s what we ski on around here”. Who am I to argue. A day or two in and they come together on piste by coming forward. Most helpful article and comments, I’m definitely going narrower.
I don’t know I kind of like the my purpose ski. I’ve been skiing the blizzard cochise for a few years now and those skis flat out rip in all conditions. That said it would be nice to have a more narrow ski on groomer days but for now I just have to commit to the speed, bend those puppies and make some big arcs. It’s all good in the end if you are out there, being safe and staying healthy 🙂
meant to post “all purpose” ski
I love my 88s…all day….
10-110s mm is a quiver killer and you need to ask yourself, ” am I skiing to survive? Or Thrive? Am I skiing to be a boomer or a zoomer” this is the later of the argument. You want to ski like a dad, but do not impose that on others.
Damn. Now I have to buy a new pair of skis.
If you want to ski like an old PSIA dork, or if you’re learning how to carve with higher edge angles, or if you are sticking to groomers, buy some skinny skis. If you want to ski fast in variable snow 105+ is your friend. It’s not only about float in powder. Powder is easy. It’s about the ability to pivot in funky snow. Skinny will skis get locked in and require aggressive unweighting to turn. Fatter skis will stay will stay relatively loose even in crud or crusts. They let you ski faster and with more control when snow is not great.
Well said!!
“If you want to ski like an old PSIA dork” hahaha you win, that’s pretty much the end of the argument right there. Thanks for the laugh, couldn’t agree more with that and the rest of your points. If you’re in any place where it actually snows fat skis are the way to go
I love by all mountain Nordica Navigator 85s, I grew up on narrow skis. Anything from Salamon, Atomic and K2 missiles. But that’s here in KY and IN on groomers. I have gotten to ski the Cascades in WA, Whitefish MT to Northern Michigan areas too. I can see where fat skis 95 to 105s would be nice on deep powder days, but fat skis are not for me, my 85s are as fat as I want to go, they rip and carve great in powder and groomers.
Thanks for the comments. I suggest you readers watch this video to review the facts and science behind my research. Many comments here are anecdotal based on personal use of Fats in powder and crud, which is not the subject of my research. Using Fats on groomers hurts knees. Foot width is also a factor in leveraging a wide ski on firm terrain.
YouTube link: https://youtu.be/rPtIwDYVrN4
Use ’em where they work!.
Right On! My shaped skis definitely made skiing a dream on groomed & ungroomed trails. I had 60 under my boot.
Definitely not for the terrain for Fat Skis..
Thanks for continued research so we decrease the stress on the knees & hips.