When it Comes to Ski Boots
Sizing is Everything
by Brent Amsbury, Certified Podiatrist
This topic alone is 50% of the battle. Independently acquired statistics indicate that at least 40% of all skiers in North America ski in the wrong size of ski boot.
Whether this is from "hand me downs", online purchases, inadequate guidance, or poor service from a ski shop, the statistics indicate that there is huge improvement potential in this area of fitting.
Sizing properly requires patience and an open mind. Your street shoe size does not usually correlate to a proper ski boot size. In the majority of cases, most skiers will find that their ski boot size is a smaller numerical value as compared to their street shoe size. For example, I wear a size 8 1/2 to 9 1/2 street shoe, and this is dependent on style and brand, but my ski boot size is either 7 or 8. This is once again dependent on model and type. For racing I will size down to a 7 and for free skiing, where I prefer comfort to precision, I will choose an 8.
To make things just a little more complicated, ski boot manufacturers use three different sizing systems. English(United Kingdom), U.S., and Mondopoint.
English and U.S. are essentially the same system, but they are one size apart from each other. For example, a size 7 U.K., is an 8 U.S. Easy right? OK, but now let's add Mondopoint.
Mondopoint is a sizing system based on the metric system, with a shoe or boot size based on the internal length of footwear. A size 26 Mondopoint is 26 centimeters long from the internal wall of the toe box to the back wall of the heel.
Do these sizings systems translate directly? No, they don't since the base unit of measurement is different. U.S. and U.K. use a base measurement of 8.47 millimeters between sizes and Mondopoint uses 10 millimeters or one centimeter between sizes. Thus it takes less Mondopoint sizes to cover the same size range of either U.K. or U.S..
Bottom line here is do not assume. Get sized at a ski shop with their sizing tools. Then, have the liner removed by a salesperson, or if you have to remove it yourself. Then, put your ski sock covered foot into the shell without the liner. Slide your foot to the front until one of your toes touches the end of the shell. Flex forward so you can see how much space is behind your heel. For a racing fit, there should be about 3/8th's of an inch between your heel and the rear shell wall. A good performance fit should have between 1/2 inch and 5/8th's. Anymore than these measurements would indicate that the boot is going to be too big, which will become quite sloppy after just a couple days of skiing.
Buying a ski boot too big is the number one malady of fitting a ski boot, so take your time shell size every model and brand before trying them on.
When you put the liner back in and try on the boot, I can guarantee you that the boot will feel quite tight, especially in the toe box. This is caused by the padding in the heel pocket pushing your foot forward and giving you a tight sensation around the toes. As soon as you are buckled, flex firmly into the tongue of boot repeatedly. Then stay in the boot a minimum of 10 minutes while standing and gently flexing. This allows enough time for the boot to warm up from your body heat and the liner material to begin to give in. The heel will have then slid back into it's appropriate pocket and the toes will have more wiggle room. The ten minutes of warm up will also allow you to assess other areas of fit.
Fit zones of priority.
While you are in a pair of boots, there are keys zones that need to be assessed, and there is specific order of priority.
The below image (Image #1) shows the areas, but the numerical order of priority is not correct. We will use the numbers solely as a reference to the specific location in the ski boot.
Area number four (4) is area priority number one. This measurement is the distance from the rear base of the heel to the instep of the foot, it also represent the volume in the heel area of the boot where the upper cuff and lower shell intersect. This area is the most difficult to change in shape or change volume for a bootfitter. Usually more material can be added, but removal is usually limited.
Look at image #2. The area in figure A, is relative to figure B. If the instep (figure A) is not secure, then the foot will tend to slide forward and cramp the toe box (figure .
Make sure that you have even pressure and contact in this zone when you buckle, and then flex. If there is impingement or pain, check to see if the boot has an adjustable tongue so it can be moved either forward or back to relieve the impingement. If the boot is very loose or there is uneven pressure in this zone, there is high likelihood that this boot has too much volume for your foot type.
If the ski boot does not fit well in this area, consider looking at a different brand or model.
Some people may experience repetitive problems in this area, but it is important to find a boot that has the best overall fit here.
Area number three (3) and two (2) are the next most important areas. Area three (3) is at the base of the heel. Ski boots are generally fairly thick here and can be reshaped or ground with a Dremel tool to improve the fit here. If there is too much room here, then the liner can be padded, but for performance skiing or racing, it is better that the plastic shell is fairly close to the foot, so padding is not an ideal option. Area two (2) is the distance between the medial and lateral ankle bones. This area can also be modified to fit if there is impingement, but if the boot is too loose, padding can be applied, but it is preferred that the plastic shell is again close to the ankle regions. Excessive padding here tends to reduce edge quickness, so having a precise fit here is critical for high performance skiing.
Area one (1) is the least important of all the fit zones recognized here in the image, even though it tends to be the most talked about by boot manufacturers. This is the width area of the boot. Of all the areas in a ski boot, this is the most elementary to reshape and modify. The area is long and broad and is easily accessed by a boot fitter. Heat stretching and grinding is very effective here so there is plenty of room for change.
Many narrow lasted ski racing boots can be made to fit very wide feet at the hand of a skilled boot fitter.
Most people tend to steer away from purchasing a ski boot if the fit is tight here, but the previously mentioned fit zones take priority, so if a ski boot fits great in all other zones except the width zone, then that ski boot is very likely going to be an excellent candidate for overall performance.
There is also a fit zone not indicated in the above image. This is at the top of the cuff where the power strap is located and where the top buckle closes the boot around the calf. Fit here is also important, but because of the easy access for the boot fitter and the mechanical range of the buckle here, fit can be easily modified to improve performance and comfort. Those with large calves or very narrow ones should look for boots that either have top buckles with extra placement positions, or have shims or spoilers in the calf area that can be either removed or added.
This is probably the least recognized when it comes to ski boot fitting since there is no immediate neuro sensation when trying on a ski boot when it comes to stance geometry. The only sensation of stance is of proprioception, where the body is aware of the ski boot putting the muscles and bone in a position that is of course different than that of a street shoe. But when the boot is used dynamically, and usually this is when the boot is already been purchased and fitted, does the ski boot show it's "fit" in terms of stance and alignment.
It is not uncommon for certain models of ski boots to promote better alignment and balance for a skier than others, so it is important for skiers looking for high performance, to consider stance and alignment of the boot as another part of the overall fit equation.
Note the image below.
The two main parameters of stance are ramp angle and forward lean. Most ski boot manufacturers provide adjustment potential in both of these areas. Forward lean is usually modified with additional spoilers behind the calf, or a mechanical adjustment on the rear upper cuff.
Most ski boots come with spoilers installed and forward lean in "stock" positions. In turn, most skiers believe that these positions are default and are suitable for their performance level. In most cases I find that these positions are not ideal, and by making measured modifications, performance can be greatly improved.
Ramp angle also affects performance immensely. It is the key to fore and aft balance, and when properly adjusted, the "sweet spot' of a ski can be easily recognized. Ramp angle modification is not quite as easy as forward lean, but removal of material from top surface of the boot board, or additional material added is well within the skill range of a good boot fitter.
For high performance skiing, it is recommended that skiers consult with ski boot fitting experts regarding their stance and alignment prior to seeking a new pair ski boots. This will unlikely change a final purchase decision if a ski boot is found to fit properly, but it will raise awareness for the potential for improvement that can be unlocked in the quest for better technique and faster skiing.
Certified Pedorthist and Masterfit Master Boot Fitter
Park City Ski Boot
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