 Poster: A snowHead
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This article used to be online, but has now disappeared. It is aimed at the coaches of junior skiers, but I've found much of the information in it to be helpful for my own skiing. Seeing as I had a saved copy I'll park it here as a resource for others...
ARTICLE 8
BOOT FITTING FUNDAMENTALS
Boot Design
All ski boots are designed to provide a solid link to the ski allowing the skier to hold a
carving edge. Boots designed with overlap construction are the equipment of choice for
ski racers. Overlap boots are constructed with two components. The lower shell
envelopes the foot and maximizes both support and sensation. The upper cuff attaches to
the lower cuff and it transmits forces from the leg to the lower shell and ski. The
attachment of upper to lower cuff should mimic the anatomic function of the ankle joint
to support mobility. Boots that significantly restrict range of motion in the ankle inhibit
performance. Some brands of boots provide adjustment features that allow the following:
• Forward lean adjustment
• Upper cuff (lateral) adjustment
• Heel lift adjustment
• Micro-adjustable buckles
Other adjustments include grinding and punching specific areas of the boot to
accommodate individual differences in foot and lower leg shape. Stretching should be
avoided unless absolutely necessary, due to the common side effect of distorting the
alignment of the toe and heel lugs.
Grinding to modify the flex pattern of the boots should only done by those who have
experience with the specific model of boot in question. Inappropriate grinding can
destroy both the rebound and lateral stability of a race boot.
Alignment strategies include:
• Foot beds to provide a supportive foundation or orthotics to correct
biomechanical problems
• Alignment of the upper cuff to the lower leg to enhance lateral balance, and allow
to the skier to stand naturally on a flat ski.
• Alterations to the liner to provide a more even distribution of pressure, and
individualize shell fit.
Due diligence should be exercised when providing foot beds to juveniles. Conservative
advice is to do nothing, but there is little evidence to support the notion of causing
permanent changes (either good or bad) to growing feet with the use of footbeds or
orthotics. For this reason, athletes with “normal” feet can still benefit from an ‘off-the-
shelf’ footbed to enhance comfort, fit, blood flow, balance, and decrease foot fatigue.
Athletes with problem feet need functional sport-specific orthotics and should be
evaluated by a sports medicine physician or podiatrist. Only licensed pedorthists,
chiropodists, or podiatrists who are familiar with the mechanics of skiing should fabricate
corrective orthotics.
Boot Selection
Boot manufacturers have different concepts of ‘normal’ foot shape and design their boots
accordingly. Some brands have several different models and shapes. The most obvious,
and measureable, differences are in the cuff, ankle, heel, instep, and toe box areas. The
following are features that should be considered in the boot design for juveniles:
• Adequate boot length (try to avoid the ‘racer’ fit concept)
• Adequate room in the toe area - width and height
• Proper width for the forefoot
• Snug fit in the heel and the ankle area
• Suitable forward flex (athlete must be able to flex the boot in a tuck position at
winter temperatures) and lateral stiffness
Boot Fitting Principles
• Know the technology of boot design and construction. Local ski shops can help
you by allowing you to try on their inventory during quiet times.
• Look closely at the shape of the foot. Is the heel narrow or wide? Is the forefoot
narrow or wide? Are there any anomalies in the feet and ankles that need to be
accommodated? Do the toes lie flat?
• Consider stiffness of the boot. Juveniles are still growing and their bone and
tendon structures are not yet fully developed. Be particularly aware of individuals
who are big for their age. They are often not as strong as they appear; therefore it
is better for the boots to have a softer forward flex for juveniles. The most
important consideration is that the boot fits well, provides strong lateral support
and allows the foot and the ankle to articulate properly.
Stiff boots reduce the range of motion in the ankle and force the skier to adjust by flexing
other joints inappropriately - an outcome called compensation. The inability to blend
and balance flex in the hips, knees, and especially ankles will inhibit the athlete’s ability
to remain in skeletal alignment which will ultimately cause early fatigue and increase the
risk of injury. In addition, a lack of articulation in the ankle joints combined with
excessive angulation will stress the knee joints as well. In summary, boots that are too
stiff disrupt mechanics, balance, relaxation, decrease performance, and increase the risk
of both chronic and acute injury. If the boots are too stiff, there can be no positive
training effect!
The “jump” test is a simple procedure that can be used to help younger skiers select a ski
boot that will enhance performance rather than hinder it. The skier should stand naturally
in the boots with his/her hands of their hips. The skier flexes the ankle to prepare, and
then jumps forward and up to land on the balls of the feet. Boots that are too stiff will
limit the range of motion in the ankles; the skier will usually jump up and back. Correct
boot fitting will allow the skier to bend the three joints of the lower body, the ankles,
knees, and hips. The skier should be able to jump forward and up, landing on the ball of
the foot and absorb the landing by bouncing or flexing with the ankles. Boots will
always be stiffer in colder temperatures and this should be considered in selection and
testing (if possible).
Boot Length
• Take liners out of the boots and place footbed (if athlete has one) in the empty
shell.
• Place feet in the empty shells and slide feet forward until light contact is made
between one toe and the front of the boot
• Flex forward and look at the gap behind the heel. You should be able to insert
one finger in the gap and wiggle it. If it’s a squeeze, the boot will fit too tightly.
If you can fit two fingers it is too big.
• Remove feet from the boot and insert liner. Force the heels well back in the heel
pockets. Stand up. It is not unusual to find liners much too tight while having the
shell fit correctly. Modifying the liner is acceptable (heat & stretchor cut the toe
box open - let the foot spread the liner open and tape it back up in its new
position). This can be done at the end of the fitting session.
Boot Width
• Move the feet back to a central position in the shells. Does the forefoot area make
contact with the sides of the shell?
• If the foot makes contact, the boot is narrow. If the foot makes contact on one
side only, the shell should be ground out and/or punched on that side, or the liner
can be trimmed to fit.
Boot Contours
• Assess the area around the ankles with bare feet in the shells. Does the shell
contour match, or align with, the position of the ankle bones? If the difference is
too great, try another brand of boots. If the difference is small, heat and punch the
shell to match the ankles.
Cardinal Rules
• A boot that is too long in length will never fit properly
• Pressure points should be fixed immediately, especially in the heel area.
Cuff Alignment
Often mislabeled on boots as ‘canting’, cuff alignment is simply lateral adjustment of the
upper cuff to match the shape of the lower leg. Cuff alignment does little or nothing to
affect the position of the knee relative to the working edge. When the cuff is properly
aligned, it allows the skier to stand on a flat ski. Compared to the lower leg shape,
excess, or positive, cuff angle (cuffs ‘out’) causes a skier to stand on the inside edges and
makes it difficult to initiate and release from carved turns. Insufficient, or negative, cuff
angle (cuffs ‘in’) causes a skier to stand on the outside edges and makes it difficult to
gain enough edge angle to create a platform and carve.
• Place the feet in the empty shells (with the footbeds in the boot) and place feet hip
width apart. Hip width means that the center of the foot (defined as a line passing
through the second toe) lies under the center of the hip joint. The gap on either
side of the leg, at the top of the cuff, should be equal. If not, make necessary
adjustments so that the gap is equal. This may require more adjustment than is
possible from any adjusting feature included with the boot. If so, with the help of
an experienced bootfitter, remove the cuff and replace it in the proper position.
Canting
Cuff alignment is an adaptive adjustment whereas canting is a corrective adjustment.
Orthotics influence the biomechanics of the foot and ankle, and canting influences the
knee. The goal of canting is to bring the knee into better alignment in relation to the
working edge by shimming the bindings or grinding the bootsole to the desired corrective
angle. Many authors have suggested that the center of the knee should fall between zero
and three degrees inside the midline of the boot. However, there are many successful
athletes that fall outside this classical range. It is probably more relevant to assess
athletes on hill to ensure that they are not grossly knock-kneed, bowlegged, or
asymmetrical in their alignment. Canting adjustments should be done by an experienced
bootfitter that can recognize pelvic misalignment and leg length differences. Boot
selection, fitting, footbeds (or orthotics), and cuff alignment should be optimized before
assessment of canting needs. Natural, symmetrical, relaxed carving skills are a good
indication that canting is roughly accurate. Elite athletes often cant their boots to an
accuracy of a quarter degree, but a discussion of that level of precision is beyond the
scope of this article. Readers interested in a further exploration of this topic can refer to
‘The Athletic Skier’, by Warren Witherell & David Evrard.
Boot ‘Verticalization’
Most race boots have a forward lean angle of 15-16 degrees, and a ramp (bootboard)
angle of 6-8 degrees. The net ankle angle is forward lean minus ramp angle, which in
most cases is around 9 degrees. This is why most people need to have at least 10-12
degrees of flexion range in the ankle (past 90 degrees) in order to ski in balance (see heel
lift section that follows). In the majority of people, this range of flex in the ankle allows
the knee to sit above the ball of the foot - an athletic ‘ready position’ common to many
sports. If a boot is verticalized, the forward lean angle is reduced along with the resulting
ankle angle. In most skiers, this can have a negative effect on balance and performance
by transferring pressure to the heel, decreasing the ability to pressure the tongue of the
boot effectively, and functionally reducing the role of the ankle joint. Nonetheless, there
seems to be a persistent underground trend towards altering boots to make them more
‘upright’. This does not include removing forward lean shims to create more room for
people with large calves, regain range of motion, and encourage a natural skeletally
aligned stance. Removing forward lean shims is often a good idea (except in those that
have thin calves). There are few clear indications for testing verticalized boots, and the
alterations are usually permanent. One group of people that may benefit from a more
upright cuff are those that have a proportionately longer lower leg and shorter foot.
Boot Tuning
When you are satisfied with the fit, go skiing, readjust, and go skiing again. Repeat as
necessary to get it right. Technical problems are often caused by poor foot mechanics,
and/or poorly fit and aligned boots.
Heel Lift
Problem - boot looks too stiff, but when stationary, the athlete can flex it appropriately.
When skiing, the athlete cannot get forward no matter how hard they try.
Possible solution - check for correct heel height. Many coaches and bootfitters will
assume that the boot is the culprit and cut the upper and lower cuffs to soften it. Always
assess heel lift needs first before making potentially unnecessary alterations to the boots.
The relationship and alignment of the calcaneus (heel bone), talus (small, saddle-shaped
bone that sits between the tibia and calcaneus), and metatarsals (long bones of the foot) is
critical. When the foot is not confined it can adjust to provide better balance. In the ski
boot it can be held in misalignment, causing imbalance. This is a controversial area
among foot specialists, since many feel that an accurate assessment of bony alignment
can only be done using both weight-bearing and non weight-bearing xrays of the feet.
Most athletes require some degree of heel lift (look at most running shoes). Deciding on
the appropriate amount of heel lift is an area of considerable misunderstanding - so,
included below are 3 methods to help make an assessment.
One subjective way to calculate heel lift height is based largely on the athlete’s ability to
interpret and judge optimal pressure distribution. This generally requires a more skilled,
intuitive, and experienced athlete.
Method 1: Select a thick, soft covered book, wide enough to allow both heels on it.
• With feet hip width apart (accurately, as already discussed), place both heels on
an arbitrary number (thickness) of pages. The athlete is going to provide
feedback while maintaining a relaxed stance.
• The athlete should focus on feeling the body weight evenly distributed between
the heel and the ball of the foot. This may be different from one foot to the other.
• When the right thickness is ‘felt’, build a lift to matchas an initial test.
• This can be built up from layers of 1/8” tempered hardboard, or hard durometer
orthotic posting material, laminated together with contact cement. Grind to a
tapered shape on a belt sander.
• Attach to the boot board and replace the liner.
Method 2: Sit the athlete on a low chair, upper legs parallel to the ground, ankles under
knees (not behind or ahead), feet parallel.
• Have the athlete keep their heel on the floor and pull up the forefoot (flex the
ankle) as much as they can, one foot at a time.
• Measure the distance to the floor from the ball of the foot, just behind the 5th toe
• 5 cm is a rough guideline for ‘normal’
• Athletes with less than 5cm can try progressively larger heel lifts based on their
range of motion (ie. 4cm - test a 5mm lift, 3cm - test 10mm, etc.)
• Athletes with small feet will have proportionately less range of motion
• Athletes with excessive range (far greater than 5cm) may sometimes require a
forefoot lift, or a decrease in the ramp angle of the bootboard.
The last method has the potential advantage of being more objective, but requires some
basic range of motion measurements to be made. Of course, introducing measurements
and numerical guidelines appears more ‘scientific’ but is no more a guarantee of success
than trial and error. Furthermore, the more measurements you make, the more you
compound your potential for error! If in doubt, let the athlete, and your assessment of
outcome (ski improvement) be the guide.
Method 3: Sit the athlete on table edge, feet and lower legs hanging relaxed, back of
knees against table edge.
• Look at lower leg and foot from the side (one side at a time)
• Ask athlete to pull toes and forefoot up to the ceiling without flexing or extending
the knee
• Estimate (if you have a good eye), or measure with a protractor (you know, the
one you kept from high school for a useful moment like this!), the angle the foot
makes with the lower leg. The lines you are using are the bottom surface of the
foot and the line that runs from the center of the knee joint to the ankle joint. A
minimum target is roughly 80 degrees.
• If you are uncertain about the athlete’s effort, accuracy, or symmetry, have an
assistant flex the foot up by pressing on the underside of the lateral (outside)
surface of the foot.
• Athletes that can only actively and passively flex to 90 degrees can test a 1 cm
heel lift
• Athletes that can actively and passively flex 80 degrees or more likely don’t need
a heel lift, but can test a small (several mm) one.
• Athletes that end up somewhere in between (around 85 degrees) can test a 5mm
heel lift
• Construct heel lifts as in Method 1….
On the hill, use flat, even terrain. Rail the skis, allowing the side cut to determine an arc.
A relaxed, centered position should be easily maintained. If the athlete can arc from turn
to turn with fluid movement and balance, boot tuning is finished. If this benchmark is not
reached, or if the athlete feels discomfort, test further lifts, both smaller and larger than
the original. Sequence to appropriate size. Watch for discomfort in the heel area caused
by the heel lift. If this occurs, grind the lift to fit.
Final Note
Minor adjustments to boots may be required during the season. It is important to act on
acute problems with boot fit, alignment, and pressure points before they become chronic
and ultimately inhibit skill development and performance.
Contributed by: Matt DiStefano and Keith Robinson
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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Very good post lots of info .
Are the contributors europe or american based or both .
The section on boot lenght confirming using the footbed placed in the shell to measure shell gap was a point I find not so easy to do but welcome info .
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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Have people got ET’s finger to be able to get it down to heel level.
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You need to Login to know who's really who.
You need to Login to know who's really who.
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I believe the whole two finger thing is just a silly ball park thing and not something to use if serious about doing it well with close tolerances .
Scarpa make fit sticks I believe and snowrock has some strange ones in three sizes they never can find ?.
Diy you can knock long wooden fit sticks up if so inclined which I did myself but imagine pro bootfitters can use a mark one eyeball .
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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Thanks. A lot of interesting stuff there, quite a but of which sits well with my own experiences and thoughts.
Is this what all boot fitters agree with, however?
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You'll need to Register first of course.
You'll need to Register first of course.
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Its got to be better than the ever changing covent garden kid doing chain store retail having done a season in morzine .
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Intuition define the standard boot fitters finger as 0.5" - so to follow the advice in the article, for junior racers...
0.5" = Not long enough,
1" = Too long.
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0.5" is 12mm aprox
1" is 24-25mm aprox
Why would anyone want further confusion converting units of measurement when everything is and can be in mm/cm/mondo
Last edited by After all it is free  on Sat 27-01-18 5:01; edited 1 time in total
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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The CSCF have also put some videos on bootfitting for the different junior age groups on youtube.
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FAQ