I was taught some careful fitting criteria for performance skis. Around the turn of the century, skate lengths had stabilized after the wild experiments of the late 1980s into the mid 1990s. Classic lengths had shrunk a bit along the way, but for performance skis still needed to be at or above 110 percent of height.
The relationship to height in performance classic is more to stride length and weight shift than just height per se. In a casual shuffle or a back-country plod, stride length isn't a factor. But if you want to move along smartly on a groomed or at least well-packed trail, you'll want a ski that tracks smoothly as you swing your legs through a longer arc. You want enough ski up front to support your weight shift down the axis of the track as you accelerate.
Skate skis use length in their own way. You might wish from one day to the next that your skating skis were shorter or longer, depending on the firmness of the snow and the steepness of the terrain. As the ill-fated Fischer Revolution taught us in the early 1990s, there's definitely such a thing as too short. However, not long before that, early skate-specific models had demonstrated that they can be too long, as well.
If you're six feet, four inches tall or taller, you'll do fine on a skate ski that's 200 centimeters. In the early years of skate-specific gear, you could get skis that long or longer.
Average trail width was a big factor in trimming ski lengths. Since skate skiing was only done on firmly groomed trails, a skier didn't need the flotation provided by the traditional skis of old. That fact, plus the narrow trails at most touring centers, led to the 147cm, "one size fits all" skating ski. It was never intended as a racing ski, only a convenient way to allow many skiers to fit the new technique into trails that had not yet been widened to facilitate it.
Racing skate ski lengths dropped down for a few seasons as manufacturers and skiers alike felt around for the right balance of length and stiffness. By early in the 21st Century, skate ski lengths had settled pretty close to where they are today. For adults, lengths range from 172-ish up to 190-ish.
According to guidance around the turn of the century from the Peltonen ski company, a venerable Finnish manufacturer, skating skis should fit between 106 and 110 percent of height to provide the optimum balance of maneuverability, propelling edge, and glide length. Taller skiers would end up getting stuck with skis that didn't hit that window, but they were already accustomed to fitting into our world of low doorframes and short beds.
Along with length came flex. The mid section of a skating ski pops in a similar way to a classical ski, but for a different purpose. A properly fitted skating ski never flattens out completely. That center section does not need to touch the snow and stop for a moment, the way a classical kick zone does. Instead, the skate camber absorbs energy as you put your weight on it and returns energy as you unweight it to shift to the other ski. The gap also interrupts the glide zone, which helps to expel free water in warm, moist conditions.
When a ski is properly fitted to weight, the skier can get a comfortable amount of glide zone onto the snow, with the pressure well distributed along it. Too stiff a ski means the glide zones are effectively farther from the foot, farther from where the weight is applied to the ski, and the rebound when you unweight will punch up. The action on and off of the ski might feel unstable and erratic. Too soft a ski can mean that the whole base contacts the snow. The pressure points in the glide zone will sit close to the foot, while tip and tail have too little pressure on them because the ski is being mooshed down in the middle.
The weight relationship is nowhere near as exacting as in performance classical, but there are limits. The same goes for height. You might do fine with skis that fall a centimeter or two outside of optimal, but go just one more and you feel like you're a mile out. Also, on softer snow you might really like the longer end of the fit range, while on hard, fast conditions you would prefer the shorter end. Too short in those conditions can be grippingly squirrelly.
The ski shop is a gray area. The person selling you skis wants to sell you skis. The better ones will start out with the goal of selling you skis that are perfectly dialed in, but once they look at the rack they will try to make a case for whatever they have on hand.
Twice now I have listened to the other salesman here fudge the numbers to sell a ski set to women looking for skate setups. In the first case, I had opened the sale and went to check on whether we could order her a dialed-in fit. The other salesman stepped in and did a fudge fit that will be usable, but could be a little bouncy and a hair short. He's also 6'2", so maybe misery loves company when it comes to never getting a 106- to 110-percent fit.
In the second case, the ski strikes me as way above range flexwise, although the height might be pretty good. There was a ski of identical length with a softer midflex number, that he didn't choose. I don't know whether price was the factor there or if the woman is a lot heavier than she looks. Weirdly, the weight range on the softer ski was listed as higher than on the stiffer ski, but the midflex (tested at the Fischer factory) was softer than the low end of the general range for the ski.
Scanning the almighty internet for guidance on what the real racers and race oriented shops are doing, I found a lot of conflicting information. Caldwell Sports seemed like a good honest broker. Their fitting criteria breezed over height and focused on weight. But racers tend to be conveniently height-weight proportionate. A certain weight more or less corresponds to a general height, so that height doesn't need separate and detailed scrutiny. Caldwell addressed it by referring to average builds among male and female skiers in different general weight ranges. So height is hidden in there, but they have that gray area in which to fudge a fit.
In an era when ski companies are telling us that we should be able to move our bindings up to three centimeters either way to get the perfect ride, they can't turn around and tell us that ski length overall doesn't matter. They still do, but don't just nod along. Try to part the fog a little to see where you are in their gray area.
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