Dit s de nieuwe benadering bij het skiën. Situatief skien is zich steeds aanpassen aan de omstandigheden. De situatie, dat kan de soort sneeuw zijn, de ondergrond en de hellingshoek. Dat is meer dan een skitechniek, zoals het carven, toe passen. Het is dit, bestaat niet. Het is afhankelijk van de omstandigheden of situatie.
Situatief Skiën kan daarom meer zijn. Er zijn wel binnen de verschillende ski-disciplines overeenkomsten. Fundamentals welke overal terug komen. Deze zullen eerst in de skiles geleerd en getraind moeten worden om zo een brede basis te krijgen.
De brede basis en de daarbij behorende fundamentals zijn bij Portes Du Ski belangrijk in de lessen. De fundamentals zijn: gewicht verplaatsen, ski’s vlak leggen (druk er af), ski’s kanten (druk er op). De druk ontstaan door de ondergrond op de ski’s. Deze drie elementen komen steeds terug bij elke richting verandering.
Na het lezen van het artikel, helaas in het Engels, kan het volgende geconstateerd worden.
Conclusie bij situatief skiën.
Situatief skiën is veel meer dan slechts een techniek leren beheersen. Het situatief skiën is zich steeds aanpassen aan de omstandigheden. Binnen het situatief skiën kunnen we wel bepaalde fundamentals terug vinden die in elke situatie zich voordoen.
Naast het oefenen en trainen van deze basis fundamentals zijn er nog tal van andere bewegingen die geleerd of getraind kunnen worden.
Bij situatief skiën gaat het om hoe te bewegen op en met de ski’s. Anticiperen op, als ik deze beweging maak, dan doen de ski’s dat. Dat zijn wetmatigheden. Daarom wat moet er gebeuren, welke bewegingen horen daarbij. Welke externe krachten werken er op ons lichaam en hoe moet het lichaam hierop reageren via de interne krachten.
situational skiing of situatief skien.
Situatief skien covers the areas beyond technical on-piste skiing. It focuses on what to do when conditions and/or terrain changes. This chapter concentrates on hard pack, bumps, powder, steeps and variable snow. Once again a three phase turn is utilised, however unlike the previous chapter which highlighted the relevant movements required to develop each area, this section covers each of the four movements through the different situations. This is because skiers at this level will have varying degrees of experience with each of the situations and therefore their needs are more complex.
The progressional section will highlight areas to concentrate on for introducing skiers to each situation and will provide developmental ideas for improving skiers within each of those situations.
situatief skien on hard pac
Hard pack snow generally occurs on-piste and refers to firmly compacted snow that offers little in the way of edge penetration. It is often referred to as ice.
- minimal penetration of skis into snow
- less friction between the skis and the snow
- fore/aft – focus is on a wider and lower athletic position
- rotational – the rate of rotation needs to be consistent and controlled
- lateral – the base of support will be wider than normal and the skier may choose to reduce the amount of lateral movement of the centre of gravity inside the turn and/or edge angle
- vertical – vertical movement will be reduced and the overall athletic position of the skier will be slightly lower than normal
To create stability and muscular tension, the athletic stance of the skiers will be lowered through a flexing in the joints and the width of the stance will also be increased. This will allow skiers to deal better with the lack of edge engagement that can occur on hard pack.
Due to the reduced friction between the skis and the snow it is very easy to turn the skis so the focus needs to be on the rate of rotation. Legs should be rotated consistently throughout the turn under a stable upper body.
In conjunction with a lowering of the stance (vertical movement) a widening of the base of support is useful. This will increase stability and allow the edges of the ski to be engaged without having to move the centre of gravity too far inside the base of support. The focus on edging the skis will be on the legs inclining (angulation) rather than the centre of gravity moving towards the inside of the turn. Lateral balance on the outside ski will aid snow penetration, so as the legs incline to create edge angle the upper body will balance towards the outside ski creating more pressure on the outside ski.
Vertical movements will be reduced and should be made slowly and with muscular tension. Vertical movements should be directed along the length of the ski rather than to the inside of the base of support. This combination of a lowered stance and slow, controlled vertical movement will help the skier remain stable should the skis begin to slide sideways during the turn.
Terrain and speed are important considerations when teaching on hard pack. Select terrain that skiers are comfortable with. The difficulty in engaging the edges suggests an initial focus on widening and compacting the athletic position followed by smooth consistent leg rotation. As skiers become more comfortable with the situation or for skiers with more experience in these conditions, the focus will change to subtle edging skills and developing a feel for the edge along with the appropriate amount of pressure to apply to create edge engagement. Slow controlled vertical movements will aid this.
situatief skien with bump skiing
Bumps are created by skiers turning in soft snow. With each turn the snow is pushed into small piles which over time become bumps. Bump skiing requires the co-ordination of all the movements over constantly changing terrain.
- slope is constantly changing angle
- edge angle is dictated by terrain and line choice
- skis are generally closer together than when skiing dynamically
- fore/aft – constantly changing terrain challenges fore/aft balance
- rotational – strong rotation of the legs under a stable upper body is needed
- lateral – the centre of gravity stays more above the base of support
- vertical – vertical movements are used to aid fore/aft balance, pressure control and blend lateral and rotational movements. The timing of the vertical movements will change
Skis can be going downhill on one turn and uphill (going up the back of a bump) on the next when skiing bumps. This change in terrain can also happen within the phases of one turn. This challenges the skier’s fore/aft balance. For skiers to stay in balance they need to remain perpendicular to the slope angle but must make adjustments for the bumps, with the result that the skier is perpendicular to the slope angle, but not necessarily perpendicular to the angle of the snow created by the bump. Small flexion/extension movements of the ankle – dorsiflexion and plantiflexion – can be used to help maintain fore/aft balance. These small movements alone may not be sufficient to maintain fore/aft balance therefore vertical movement becomes an important element in aiding fore/aft balance.
Bump skiing requires the ability to vary the rate, intensity and timing of rotational movements. The legs are rotated under a stable upper body, creating good rotational separation. Choice of line will affect the skier’s ability to rotate the skis. Turns made on top of bumps will require less rotational effort as there is less ski/snow contact and therefore less resistance.
The pole plant is an important ingredient for bump skiing. It is used for stability and as a turning force when the skier flattens the skis and starts the turn. The pole plant can be used for balance when the feet are being turned on top of the bump.
Generally in bumps the skier needs to use a smaller range of lateral movement and to keep the centre of gravity over the base of support rather than moving inside the turn. The reason for this is that the angle of the edge needs to be reduced to allow for quick changes in direction, and controlled skidding when necessary, to control speed. It is harder to control speed through turn shape now that the shape of the bump largely dictates the shape of the turn.
The edge angle of the ski is largely dictated by the shape of the bump and depends on the line the skis take as they are steered into the trough. If they go wide they will be relatively flat and more against the neighbouring bump. If they stay in a more direct line they will engage with a high angle against the side of the bump they are turning around. Skiers need to become aware of how the terrain acts against the edge of the ski so that they can use the terrain for edge control. Once they understand this they need to develop fine adjustment ability in the ankles (inversion and eversion) for more edge control.
Bumpy terrain affects pressure control. Vertical movement is needed to absorb the changes in terrain to control pressure on the skis and maintain good fore/aft balance. Flexion is used to control pressure as the skis approach the top of the bump and extension is used to maintain pressure as the skis travel down the backside of the bump. As the skier develops vertical movement to manage pressure in the bumps the timing of these movements throughout the turn changes. The skier is flexed at the initiation of the turn (on top of the bump) and needs to extend during the control phase (into the trough). This means that the centre of gravity is moved over the base of support while flexing rather than while extending.
The progression presented to students will depend on their bump skiing experience. Skiers who haven’t been in the bumps before will need a focus on remaining well balanced through a combination of fore/aft and vertical movements, while skiers with some experience in the bumps will focus on pressure control and the related change in timing of vertical movements to achieve this.
The line selected to lead the group through the bumps can have a bearing on the success of the lesson. First time bump skiers will ski a more rounded line, with the initiation of the turn taking place on the top of the bump and the skis following a line that uses the sidehills of each bump, while more experienced bump skiers may take a more direct route using the troughs of each bump. The line will also dictate the movement focus. The rounder line will focus on rotational movement and the timing of the rotation, while the more direct line will have a vertical movement focus concentrating on pressure control.
situatief skien powder skiing
The goal of linking rhythmical turns down long powder runs is the dream of many skiers but powder does create many challenges. Skiers must get used to both the fact they can no longer see their feet and skis and the increased resistance from being in the snow rather than on the snow.
- skis are in rather than on the snow
- skis are generally closer together
- the snow compresses under the skis to create a platform
- ski/snow pressure should be more evenly spread between both skis and across the entire base of each ski rather than being along the edge of each ski as it is on groomed terrain
- turnshape will be shallower due to increased snow resistance
- skis are less likely to skid when in the snow
- fore/aft – increased resistance due to being in the snow
- rotational – more effort required to turn the skis
- lateral – narrower stance
- vertical – vertical movements are used to aid fore/aft balance, pressure control and blend lateral and rotational movements. The timing of the vertical movements will change
When skiing powder there is increased resistance due to the skis and boots being in the snow rather than on the snow. This slows forward momentum and therefore fore/aft balance needs to be adjusted to keep the centre of gravity over the centre of the feet. To maintain a good centred stance and to stop the upper body from being thrown around, muscular tension, especially in the core muscles is needed. To be balanced in the powder the centre of gravity needs to be perpendicular to the ski. The skis may be tipped at different angles to the slope depending on the way the snow is compressing under them.
The increased resistance that challenges fore/aft balance also makes it harder to turn the skis. Rotational movements will need to be stronger and applied with more intensity to achieve the same results as on-piste. The rate of rotation needs to be consistent throughout the turn with the goal being for the ski to travel in a smooth arc.
Stance is narrower with a focus on more even pressure on both skis so that the amount the skis sink into the snow is even rather than one ski sinking a lot further than the other. To create a platform the skis still need to follow a path that is wider than the path taken by the centre of gravity, and this combined with a consistent rate of rotation will allow the skis to tip on to their edges and slice through the snow. The platform will develop progressively as the snow compresses under the skis. Due to the compaction of the snow under the entire width of the ski it is easier to create a platform.
Active vertical movement is essential for powder skiing success. It will help control the pressure created and aid the steering of the skis. At turn initiation the skis need to be bought back toward the surface of the snow to make them easier to turn. This can be done with an active extension movement (suitable for less experienceed powder skiers) or with an active flexion (retraction) movement. A well-timed and consistent pole plant will aid vertical movements.
Momentum is a key tactical element to skiing powder for both the inexperienced and experienced powder skier as it will allow skiers to keep moving through the snow and to create pressure on the skis to aid turning. A short turn is the generally accepted norm for powder skiing as it allows the centre of gravity to continue moving down the hill, although changes in ski technology (wider skis, rocker technology) have made longer turns easier to achieve in deep snow.
First-time powder skiers will need to develop the skills to maintain an athletic stance as the pressure from the snow increases and decreases around their boots/legs and to increase the intensity of rotation to be able to get the skis to turn while in the snow.
situatief skien variable off-piste skiing .
Skiing presents many challenges and while this chapter outlines some of the more common snow conditions and terrain challenges there are many other conditions that have not been covered. These can vary from chopped-up powder, wind packed snow, breakable crust, rain affected snow or spring slush. The diverse and changing conditions found off-piste means that there is no one technique, but rather a combination of the techniques used for powder, ice, bumps, steeps and groomed terrain are required.
- skis will vary from being in the snow to being on the snow
- skis need to be edged or tipped up to slice through the snow
- pressure along the base of the ski will change as snow conditions vary
- fore/aft – changing snow conditions will constantly challenge fore/aft balance
- rotational – rate of rotation will vary to meet changes in terrain and snow conditions
- lateral – the amount of lateral movement will be dictated by the snow conditions
- vertical – a shorter range of movement and the ability to change the timing of the vertical movement is require
The inconsistent nature of the snow will constantly challenge a skier’s ability to maintain a centred athletic position. Core stability will help maintain this along with the ability to move the feet backwards and forwards under the centre of gravity. The ability to look ahead and anticipate the effect the changes in snow condition will have on the skis is also an important element to maintaining an athletic stance.
The amount of rotational force required is governed by the snow conditions. Heavy snow will require more intense rotational movement while harder snow conditions will require less intensity. The one constant is that a consistent rate of rotation is required to guide the ski through an arc. Once again the ability to look ahead and anticipate changing snow densities will assist skiers in applying the appropriate amount of rotational force.
The amount of lateral movement applied is determined by the ski/snow interaction. If the snow is compacting under the ski and creating a solid platform then the centre of gravity can move further inside the turn and weight will be distributed more evenly between both feet. Conversely on harder snow the centre of gravity will stay more above the ski and balance will be more directed toward the outside ski. Developing a feel for the ski/snow interaction is an important element in developing lateral balance.
Changing snow conditions will be managed more easily with a limited or shortened range of vertical movement. The timing of vertical movement may change from turn to turn as snow conditions change and a limited range of movement will make the ability to adjust timing easier. Pressure control is another area which is constantly changing in variable off-piste conditions, and once again developing a feel for the ski/snow interaction will help skiers use appropriate vertical movements to control the pressure on the skis.
The methods used to ski variable off-piste conditions will depend entirely on the snow conditions so elements of skiing powder, ice, bumps, steeps and groomed terrain will all come into play. The ability to look ahead and anticipate changes in the snow and developing a feel for the ski/snow interaction will greatly enhance the ability of all skiers to deal with these challenging conditions.
situatief skien skiing the steep.
All skiers face the challenge of skiing on steeper terrain as their skills progress, e.g. moving from a green run to a blue run. For the advanced skier, steep terrain relates to the steepest slopes the ski area has to offer, be it black or double black terrain. Steep terrain is generally found off-piste therefore snow conditions add to the physical and mental challenges posed by the increase in slope angle.
- edge angle increases at a faster rate after the fall line and is highest in the completion phase of the turn due to the gradient of the slope
- skis accelerate rapidly into the fall line
- skis may leave the snow during turn initiation
- fore/aft – difficult to keep the centre of gravity over the centre of the skis
- rotational – rate of rotation needs to be increased
- lateral – upper body needs to be stable. Edge engagement occurs later in the turn than on easier terrain, and is a result of rotational movement of the legs, rather than a movement of the centre of gravity inside the turn
- vertical – flexion/extension movements need to direct the centre of gravity along the length of the ski and to aid controlled movement across the base of support
As the turn is initiated and the skis go from across the hill to pointing down the hill, the relative angle of the slope increases dramatically. As the skis accelerate down the hill, fore/aft balance can be managed by either moving the feet forward or back underneath the body, or by moving the body forward or back relative to the feet. Fore/aft balance is constantly challenged and vertical movement is an important factor in keeping the base of support under the centre of gravity.
To maintain speed control, turns in the steeps will generally have a shorter control phase. To achieve this the rate of rotation needs to be increased. However the skis will still need to be turned across the slope sufficiently, to control speed, so the duration of the rotation is maintained although the rate has been increased. The high edge angle through the completion phase of the turn will also necessitate an increase in the intensity of rotational effort. The pole touch plays an important role in rotational movement, blocking rotational movement of the upper body and creating increased rotational separation which aids lateral balance. The pole is touched further down the hill, and stays in contact with the snow longer than on flat terrain.
Edge engagement in steeper terrain generally happens later in the turn (towards or in the completion phase) than on flatter terrain. The skis stay more under the centre of gravity rather than travelling in a wider path than the centre of gravity as they do on flatter terrain, and the edging is a result of inclination of the legs (resulting in greater angulation) and the steepness of the slope. Upper body stability plays an important role in maintaining lateral balance; this is developed through a combination of rotational separation, and angulation in the hip and spine to balance on the outside ski as the centre of gravity moves towards the inside of the turn during the completion phase. The pole touch plays an important role in upper body stability.
Vertical movement plays an important role in keeping the centre of gravity balanced over the base of support in steep terrain. A lower athletic stance provides more stability and increased muscular tension and allows skiers to turn their legs more strongly and access more lateral leg movement. Flexion/extension movements need to direct the centre of gravity along the length of the ski as well as aiding in the release of the edges. In very steep terrain it can be appropriate for the skis to leave the snow at the initiation of the turn and be redirected in the air. This can be achieved through increased intensity in the vertical movement. In these instances ski/snow contact can be regained anywhere from the top of the control phase through to the completion phase depending on the steepness and narrowness of the slope. The extension movement at the initiation of the turn can be replaced with a retraction movement by more experienced skiers.
Progressional Focus. situatief skien.
Terrain selection is an important factor when skiing the steeps. While safety is the prime consideration, snow conditions, hazard assessment, length of run and students’ fitness also need to be taken into account. Ensure that students want to ski steeper terrain as confidence will be a key ingredient to their success. As terrain gets steeper a focus on moving with the skis to maintain a centred athletic position will set skiers up for success. This could then be followed by a focus on the completion phase of the turn.