AY Honors/Skiing - Cross Country/Answer Key

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Cross-country skiing (also known as XC skiing) is a winter sport popular in many countries with large snowfields, primarily Northern Europe and Canada.

File:Finnish Soldiers Skiing.jpg
Finnish soldiers on skis. Like in most of the other Scandinavian armies, virtually every infantry soldier is given ski training in the Finnish army.

Cross-country skiing as a sport is part of the Nordic skiing family, which also includes ski jumping, and a combination sport of cross-country skiing and ski jumping called Nordic combined. Free-technique cross-country skiing is also the method of locomotion in the combination sport of Biathlon, which adds rifle shooting to skiing. As a sport, cross-country skiing may be viewed as a kind of "bushwalking on skis", where skiers tackle trails of various lengths and difficulties. Some skiers stay out for extended periods using tents and equipment similar to bushwalkers, whereas others take relatively short trips from ski resorts.

Equipment

The skis are long and thin, to distribute the weight of the skier and allow the skier to move quickly. Typical ski dimensions are 2 metres in length, about 5 centimetres in width and one centimetre in thickness.

As in downhill skiing, cross-country skiers carry two poles, usually made of aluminium or fiberglass. More expensive poles are made of graphite or some other light material. Poles have a spike at the end to provide a fixed pivot when the pole penetrates through to a hard surface, and a plastic ring (or basket), to provide extra purchase in snow and to ensure the pole doesn't sink too deeply.

The toe of the skier's footwear is attached to the ski with a binding, whilst the heel remains free.

Equipment differs according to skiing technique. Skating or freestyle poles are usually longer than those used for the classic technique. Typically, skating poles should be long enough to reach the skier's chin or as far as the eyebrows, depending on the skier's preference. In contrast, classic-ski poles should reach the skier's armpit.

History

Recreational skiing in Kananaskis Country, Alberta.

Cross-country skiing originated in Scandinavian countries in prehistoric times. It may have also been practiced by Native Americans for similar lengths of time, although the Norwegian emigrants Snowshoe Thompson and Jackrabbit Johannsen are widely credited for introducing the sport to North America.

The sport has been used by explorers by means of transport, and all Scandinavian armies train their infantry on skis for winter operations. Traditionally, all of the equipment was made of natural materials: wooden skis and bamboo poles with leather hand straps. Footwear was usually sturdy leather boots with thick soles. Bindings evolved from simple straps made of twisted wood-based thread, to the so-called Kandahar binding with the fastening of both the boot’s front and back, to the ‘Rat’s Trap’ front-only binding, which is today known as the Nordic norm, and has evolved in various modern bindings.

Bindings/Boots

The three binding systems used in Cross-Country Skiing are; NNN (New Nordic Norm), SNS Profil (Salomon Nordic System Profil), and SNS Pilot (Salomon Nordic System Pilot Skating.) These systems are somewhat different from one another.

New Nordic Norm (NNN)

NNN bindings (made by Rottefella, Rossignol, and Atomic) can range from BC (Backcountry) to the R3 Skate and R3 Classic (Best bindings that can be installed on any ski) to the NNN R4 NIS (Bindings that require a special plate on the skis to be mounted.) Boots compatible with these bindings are made by Alpina Sports, Atomic and Rossignol. The R3 and R4 are generally the choice for World Cup Racers using NNN. The thing that best distinguishes these from SNS (Salomon and Fischer) bindings is that all bindings in the NNN system have two ridges that stick out from the bottom of the binding. In NNN boots, there is slots for these two ridges to fit. NNN is said to have better steering than Salomon because they have two grooves (which better distributes the weight) rather than SNS's (both Profil and Pilot) "bar" sticking up from the binding that fits into a sole in the boot. NNN has also been proven to be lighter than SNS bindings.

The R4 NIS binding (made by Rottefella and Rossignol) is the top of the line NNN binding. These bindings are compatible with any NNN boot (the bindings are almost the same as other NNN bindings,) but can only be used on Rossignol X-IUM or Madshus Hypersonic Skis (the companies best racing skis.) Madshus is part of the Rottefella/Madshus/Alpina partnership, and that is the reason for Madshus skis having NIS bindings. The reason for only two different skis being able to use these bindings is that NIS bindings require a special plate only available on these skis. The interesting thing about these bindings is that the rear part can be pivoted back and forth on the plate to match the boots' length, therefore making better power transfer between the boots and the skis. The bindings made their debut in 2005 to the public.

Salomon Nordic System (SNS) Profil

SNS bindings (made by Salomon and Fischer), however, have their advantages too. Boots that are compatible with the SNS Profil system are made by Salomon, Fischer, Adidas, and Hartjes. SNS Profil bindings are used for both Skating and Classic. These boots have only one axes at the front of the sole (this is what makes it different from the Pilot, they have two axes.) Profil bindings are generally the standard binding for SNS users. Profil comes in "Equipe" models (Racing; Equipe boots and bindings are the best/most expensive,) Active (Recreational Racing/Combination), Auto Touring, and Back Country.

Salomon Nordic System (SNS) Pilot

SNS Pilot bindings (are compatible with Salomon, Fischer, Adidas and Hartjes boots) are only used for Skate Skiing. These are used mostly by Elite skiers (Collegiate/Olympians/World Cup/National) skiers, although it is common to find High School/Citizen Racers with these bindings and their counterpart boots. Pilots are more expensive than Profils (about 100 dollars for a pair,) but can only be used for Skating because there are two axes. In Pilot boots, the two axes (one positioned about 1" behind the front axes) click into two different slots in the Pilot binding. Profil boots only have one axes and therefore, cannot fit into Pilot bindings. However, Pilot boots can fit into any Profil bindings (due to a small space behind the front of the boot for the other axes.) The reason Pilots can't be used for Classic is that Classic boots need to be able to flex in all directions so that a good "kick" can be achieved. Pilots do not have that kind of flex required in Classic, but they have been proven as good Skate bindings because skis with Pilot bindings don't move around in the air as much as skis without Pilot bindings.

Waxes

Main article: Ski wax

There are a wide variety of waxes for Nordic Skiing. The waxes can be classified into three main categories: glide waxes, kick waxes, and klisters.

Glide wax

Glide waxes are used to make a ski glide faster, and are applied by ironing onto the ski. Glide waxes range widely in price, depending on quality; racing waxes can be very expensive. Glide waxes are applied outside the kick zone of classic skis, or to the full length of skate skis. They are the only type of wax used on skating skis.

Kick wax

The purpose of kick wax is to provide grip on snow when weight is transferred on a ski; they are used on classic skis only. Kick waxes are applied in the kick zone of classic skis if the ski is not a fish-scale, waxless ski.

Kick waxes are classified according to their hardness: harder waxes are for colder and newer snow. Using a too hard wax will not give sufficient grip, while a too soft one will cause the formation of an ice soles that will slow the skier down. It is not uncommon to apply a new layer of wax if the weather changes, or when moving in altitude.

Kick waxes generate grip work by being penetrated by snowflakes when the skier puts his weight on the ski. Colder snowflakes are harder, and so is newly fallen snow. The most appropriate wax is the one that is soft enough to generate grip, but also hard enough not to accumulate snow and create a sole.

Waxes are usually colour-coded: the most common are red is for temperatures above 0˚C, and blue for below. There are many other colours for more specific temperature ranges, for instance violet for around 0˚C, green for below -10˚C, and white for below -15˚C. The snow-temperature range given by the producer must be taken with a grain of salt, since new snow will require a harder wax.

Guessing the right hardness is difficult, and the varying condition of the snow can make the right choice wrong after a few hundred metres. Furthermore, the snow in the beaten track is usually much different from the one immediately surrounding it, and works best with a softer wax. Thin snow soles can often be dealt simply by beating the ski on the track after kicking, the opposite problem may be handled by skating.

Klister

As the snow becomes older and snow flakes lose their sharpness, in case of re-freezing or of water, kick wax cannot provide any more grip, and it becomes useless. One must therefore resort to klister, which is basically a glue-like paste ("klister" actually means "glue" across all the three Scandinavian countries). Klister is discouraging for amateurs, as it is very sticky, it is easy to apply but very difficult to remove.

Professionals often maintain that klister is best applied with the palm of the hand, but it is generally not clear how to clean the hand afterwards; amateurs often resort to some object of the appropriate size. Since klister is an organic chemical, a non-polar solvent (such as gasoline) or a soap is necessary to remove it. Stores often sell purpose-made solvent to clean skis. These should be used with care, as they are both flammable and toxic if inhaled.

Klister is also colour-coded, with red klister for wet snow and blue klister for icy snow.

Waxless skis

In recent years, waxless skies have obtained some success in the market. Waxless skis have normally a fish scale pattern in the kick zone that is supposed to provide the grip. A waxless ski is inferior to a finely tuned waxed ski, but does not require waxing (except some seasonal protective waxing).

Sports events

Today, there are several types of cross-country competitive events, involving races of various types and lengths, as well as biathlon, involving a combination of cross-country skiing and rifle shooting.

The Winter Olympics, the FIS World Championships and the FIS World Cup events have long been a showcase for the world's fastest cross country skiers. There are also special distance ski races, sometimes called ski marathons, like Vasaloppet in Sweden and Birkebeinerrennet in Norway. The skiing styles in these races might be fixed, or, in case of the so-called "double pursuit" event, the two styles are used each in their own separate half of the race (with a change of equipment in "pit stops" half way through).

Techniques

There are three main techniques used in cross-country skiing. Specially adapted equipment is available to suit each.

The Classical technique was the first technique that was used and although not the fastest (in the same way as the breaststroke swimming technique) it is still used today by many, especially beginners, as it tends to be the simpler easier to learn, but take many years to get really good.

The skating Technique, developed as a result of racing and is harder to learn but once mastered the skiers can travel much faster. Skating can also be mastered faster than classical.

Telemarking is a technique used to go down hill on Cross country skis. Usually the skiers will use the classical technique for going up the hill and telemarking to ski down steep downhills.

Classical

To move when on level ground or uphill whilst using the classical style, cross-country skiiers use a running-like action. When full bodyweight is placed on the ski to flatten it against the snow (skis have camber, and a properly fitted pair of classic skis will leave the centre section of the ski clear of the snow when weight is evenly distributed between a pair), the centre section of a classic ski will either have "fish scales", or ski wax that will stick to the snow (called the "kick zone" or "grip zone" of the ski). This gives the skiier grip with which they can propel themselves forward. Because of the difference in static and sliding friction, the ski that the skiier lands on after each push will not immediately grip, but will slide a short distance. Skiiers also use poles to assist with balance and propulsion, in varying amounts depending on terrain, fatigue and speed. The arm opposite the leading foot is reached forward and the pole is planted. This technique is called "diagonal stride".

During races in the classic technique, flat and very slight uphill terrain will be double poled, where the skiier keeps their legs together and pushes simultaneously with both poles. This action can be applied at speeds where the snow is moving past too quickly to apply the "grip-and-kick" diagonal stride. At intermediate speeds, a "kick-double-pole" technique is sometimes used when the skiier is still moving too quickly to diagonal stride, but is having difficulty double poling (typically in slight uphills, or at the bottom of a long hill when just before switching to diagonal stride). Some long races in reasonably flat terrain will see racers double poling almost exclusively for the majority of the race (one good example of this is the Swedish Vasaloppet, a 90km race that takes the winners around 4 hours to complete).

When reaching a downhill slope, they are able to coast down in a similar manner to downhill skiing, or may use Telemark technique - see below.

The classical style is often performed on prepared trails (pistes) that have pairs of parallel grooves cut into the snow, one for each ski, and consequently a special long, narrow and light ski is usually used.

When skiing away from prepared trails, a much wider ski is usually used. When used by the local population of flat regions, such as parts of Finland, the skis may also be much longer, sometimes exceeding 3 or 4 m (yards) in length.

Free

Skiing by free technique/skating.

Free technique (Freestyle is a descriptive word only correctly applied to a ski sport where the competitors compete over a mogul course and by performing aerial gymnastics such as spins after launching from a short ramp in the snow), aka skating, involves the skier pushing one ski outward with the ski angled, so that the inner edge of the ski is driven against the snow, much like an ice skater. It is also important to balance on one ski to be efficient. Skis tend to be shorter than those used in classical technique, and poles longer. There is also no fish scale or sticky wax applied and no kick area. There are various combinations of ski and pole movements to suit the terrain and conditions. The technique is only suitable for use on prepared trails (pistes) or those with firm, smooth snow. In some places where the snow melts slightly at the beginning of spring a person can ski on the crust.

The distinction between Classic technique and Free technique is made in competition i.e. a race will be designated as Classic or Free*. In the case of the former only those propulsion techniques that are considered 'classic' are allowed whereas in the latter the competitors are free to use any technique although the majority of competitors will opt to skate since it is marginally faster than the traditional classic technique. This is a direct parallel to the world of competitive swimming where in a freestyle race competitors can use any technique but will normally use the Australian crawl stroke.

Recent developments in the sport include 'Continuous Pursuit' races where the competitors complete the first part of the event using the classic technique and the second part using the free technique.

Telemark

Main article: Telemark skiing

The Telemark technique is particularly suited to backcountry skiing (off piste cross-country skiing). While first and foremost it is a technique for descending, for those with dedicated equipment it is effectively a separate branch of skiing that takes place in the backcountry (off piste).

See also

External links

ca:Esquí de fons de:Skilanglauf es:Esquí de fondo o nórdico et:Murdmaasuusatamine fr:Ski de fond it:Sci di fondo ja:クロスカントリースキー nl:Langlaufen nb:Langrenn nn:Langrenn sv:Längdåkning