Parallel turn

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The parallel turn in alpine skiing is a method for turning which rolls the ski onto one edge, allowing it to bend into an arc. Thus bent, the ski follows the turn without sliding. It contrasts with earlier techniques such as the stem Christie, which slides the ski outward from the body ("stemming") to generate sideways force. Parallel turns generate much less friction and are more efficient both in maintaining speed and minimizing skier effort.

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The parallel turn was invented in the 1930s by Austrian ski racer Anton Seelos from Seefeld in Tirol. [1]

Parallel turns require solid contact from the skier's lower leg to the ski to rotate it on-edge. This was difficult to achieve with early ski equipment, limiting the technique to the high performance realm of racing. The introduction of composite skis, metal edges, releasable clamping bindings, and stiff plastic boots combined to allow parallel turns even on beginner equipment. By the late 1960s it rapidly replaced stemming for all but very short-radius turns. The evolution of shaped skis in the 1990s advanced the carving turn to preeminence.

Today parallel turns are taught to teach novice skiers the effect of weighting and unweighting their skis. They are still the basic technique for steep hills, off piste and mogul skiing.

Basic action

The parallel turn relies on two dynamics: releasing the edge hold by reducing the angle between ski and snow surface which makes the front of the ski skid downhill (skidding inwards) and then applying a force to change the edge and make the ski turn across the line of greatest slope (skidding outwards).

The skier initiates the turn by moving their knees or the whole body laterally in the direction of the desired turn. The motion of knees is translated through the calf to the high cuffs on the ski boots, to the bindings, and then to the skis. This reduces the edge hold and causes the skis to rotate on their edges, with the skier's weight and the force they put upon them to change the edge of the skis which turns them across the line of greatest slope. To stop the turn the knee or the body is rotated back to the neutral position until the edge holds and the skidding stops. While both skis take part, in practice the ski on the outside of the turn is dominant.

Moving the legs to the side shifts the center of gravity, compensated for by moving the hips in the opposite direction. The effect is to keep the skier's upper body upright while the lower torso and legs shift side-to-side. The skier pressures the front of their skis to keep the fore-and-aft center of gravity of the skier's mass over their toes.

The parallel turn can be improved through dynamic "weighting". Turns are often linked in a series of continual arcs, one direction then the other. Lifting the body through the middle of the switch partially releases the skis arcs, easing the transition to the opposite direction.

Changing the technique

In the 1990s skis were progressively widened at the tips and tails relative to the waist. Applying an edge of these "shaped" or "parabolic" skis brings a curved surface to the snow, resulting in a carve turn.

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Cross-country skiing Form of snow skiing

Cross-country skiing is a form of skiing where skiers rely on their own locomotion to move across snow-covered terrain, rather than using ski lifts or other forms of assistance. Cross-country skiing is widely practiced as a sport and recreational activity; however, some still use it as a means of transportation. Variants of cross-country skiing are adapted to a range of terrain which spans unimproved, sometimes mountainous terrain to groomed courses that are specifically designed for the sport.

Snowboard Winter sport equipment

Snowboards are boards where the users places both feet usually secured, to the same board. The board itself is wider than most skis, with the ability to glide on snow. Snowboards widths are between 6 and 12 inches or 15 to 30 centimeters. Snowboards are differentiated from monoskis by the stance of the user. In monoskiing, the user stands with feet inline with direction of travel, whereas in snowboarding, users stand with feet transverse to the longitude of the board. Users of such equipment may be referred to as snowboarders. Commercial snowboards generally require extra equipment such as bindings and special boots which help secure both feet of a snowboarder, who generally ride in an upright position. These types of boards are commonly used by people at ski hills, mountains, backcountry, or resorts for leisure, entertainment, and competitive purposes in the activity called snowboarding.

Skiing Recreational activity and sport using skis

Skiing is a means of transport using skis to glide on snow. Variations of purpose include basic transport, a recreational activity, or a competitive winter sport. Many types of competitive skiing events are recognized by the International Olympic Committee (IOC), and the International Ski Federation (FIS).

A ski is a narrow strip of semi-rigid material worn underfoot to glide over snow. Substantially longer than wide and characteristically employed in pairs, skis are attached to ski boots with ski bindings, with either a free, lockable, or partially secured heel. For climbing slopes, ski skins can be attached at the base of the ski.

Snowboarding Winter sport

Snowboarding is a recreational and competitive activity that involves descending a snow-covered slope while standing on a snowboard that is almost always attached to a rider's feet. It features in the Winter Olympic Games and Winter Paralympic Games.

Alpine skiing Sport of skiing downhill

Alpine skiing, or downhill skiing, is the pastime of sliding down snow-covered slopes on skis with fixed-heel bindings, unlike other types of skiing, which use skis with free-heel bindings. Whether for recreation or for sport, it is typically practiced at ski resorts, which provide such services as ski lifts, artificial snow making, snow grooming, restaurants, and ski patrol.

Ski binding

A ski binding is a device that connects a ski boot to the ski. Generally, it holds the boot firmly to allow the skier to maneuver the ski. However, if certain force limits are exceeded, it releases the boot to minimize skier injury, such as in the case of a fall or impact. There are different types of bindings for different types of skiing.

Stem christie Skiing technique

The stem christie or "wedge christie" is a technique used in skiing for turning. The turn comprises three steps: 1. Forming a wedge by rotating the tail of one ski outwards at an angle to the direction of movement, which initiates a change in direction opposite to the stemmed ski. 2. Bringing the other ski parallel to the wedged ski. 3. Completing the turn with both skis parallel as they carve an arcing turn sliding sideways together.

Ski boots are footwear used in skiing to provide a way to attach the skier to skis using ski bindings. The ski/boot/binding combination is used to effectively transmit control inputs from the skier's legs to the snow.

The Arlberg technique is a progressive system that takes the skier from the snowplough turn to the parallel christie through measured stages of improvement. The system, or slightly modified versions, remains in widespread use to this day. Modern ski equipment is also capable of a more efficient turning style known as carving that uses entirely different techniques and movements. Some ski schools have started moving students directly from the snowplough to carving as early as possible, avoiding learning stemming habits that may be difficult to un-learn.

Extreme carving or Extremecarving is a coined term describing a particular form of carving on a snowboard. Features of extreme carving that distinguish it from other kinds of snowboard carving include:

Carved turn

A carved turn is a skiing term for the technique of turning by shifting the ski onto to its edges. When edged, the sidecut geometry causes the ski to bend into an arc, and the ski naturally follows this arc shape to produce a turning motion. The carve is efficient in allowing the skier to maintain speed because, unlike the older stem Christie and parallel turns, the skis don't create drag by sliding sideways.

Ski geometry

Ski geometry is the shape of the ski. Described in the direction of travel, the front of the ski, typically pointed or rounded, is the tip, the middle is the waist and the rear is the tail. Skis have four aspects that define their basic performance: length, width, sidecut and camber. Skis also differ in more minor ways to address certain niche roles. For instance, skis for moguls are much softer to absorb shocks from the quick and sharp turns of the moguls and skis for powder are much wider to provide more "float" in deeper, softer snow.

Nava System

The Nava System was a ski binding and custom ski boot offered for sale in the 1980s. The system used a combination of flexible sole plate to keep the boot centered, and a spring-loaded plastic arm on the rear binding that was used to transmit sideways motions of the leg to the ski. This eliminated the need for a hard shell on the boot; the Nava boot was soft and resembled a knee-high winter boot. In spite of numerous endorsements by racing stars, the system never caught on and sales ended by the late 1980s.

Spademan binding

Spademan was a type of ski binding, one of a number of "plate bindings" that were popular in alpine skiing during the 1970s. It used a bronze plate screwed into the bottom of the boot as its connection point, held to the ski by a clamp-like mechanism that grasped the side of the plate. Unlike conventional bindings, the Spademan could release in any direction, in response to any force or torque. It provided greatly improved protection compared to contemporary designs, which generally allowed release of the toe to the sides and heel directly forward, keeping the foot attached in any other fall direction.

Rosemount Ski Boots

Rosemount Ski Boots introduced one of the earliest all-plastic ski boots for the downhill skiing market, competing with Bob Lange for the title of "first". Rosemount's design was easily distinguished by its use of the uncommon "side-entry" method for putting the boot on, which was rare at the time and is no longer used.

LW1 (classification)

LW1 is a para-Alpine standing skiing classification for people with severe lower extreme disabilities in both extremities. It includes both skiers with amputations and cerebral palsy. International classification is done through International Paralympic Committee Alpine Skiing, and national classification through local national sport federations. LW1 classified skiers use outriggers, and two skis or one ski with a prosthesis. Other equipment is used during training such as ski-tips, ski-bras, and short skis.

LW9 is a para-Alpine and para-Nordic standing skiing sport class, a classification defined by the International Paralympic Committee (IPC) for people with upper and lower limb function problems, and includes cerebral palsy skiers classified CP5, CP6 and CP7, along with people with hemiplegia or amputations. For international skiing competitions, classification is done through IPC Alpine Skiing or IPC Nordic Skiing. A national federation such as Alpine Canada handles classification for domestic competitions. This classification is separated into two subclasses including LW9.1 and LW9.2.

This glossary of skiing and snowboarding terms is a list of definitions of terms and jargon used in skiing, snowboarding, and related winter sports.

References

  1. Nick Howe: The Blitz Form Kitz, Skiing Heritage 1/1997 p.17.