In my opinion, there are two basic monoskiing methodologies. In this article, I am calling them Static Monoskiing and and Dynamic Monoskiing. The methods are distinguishable by their general characteristics.
Static Monoskiing
The outriggers are usually forward and on the snow which creates a stable “3 legged” platform. Turning is done by using the downhill outrigger to create initiate friction to force the ski tip to turn in the desired direction. This method is somewhat like steering. The ski is turned by sliding friction forces which rotate the ski around the skier’s center of mass which is generally in the middle of the ski. The ski turns and then the skier goes on a diagonal across the hill until the skier initiates another turn in the opposite direction. The overall shape of linked turns is a ragged Z.
As the monoskier leans the monoski up the hill, the ski skids through the turn causing the skier to slow down as he or dissipates energy throughout the turn which can be seen by snow throws. This type of turn can be originated from a relatively flat ski. While turning the ski never gets on deep edge. There is some edging created as the skier leans up the hill.
Turns are usually choppy. Snow is thrown through the turn as the ski scrapes and sweeps the slope as opposed to biting in and cutting through the snow. The skiers upper body is in a forward position as he or she reaches forward with the outriggers to both create the turn and maintain stability.
Think of a snowmobile. Its front runners serve the same function as the skier's outriggers. When the ski is not in the process of skid turning, it is relatively flat. As a result, the monoski tends to bounce around on all but the smoothest slopes. Therefore, speed is inherently limited. The skier will usually check his or her speed with skid turns.
Since the skier is depending upon the outriggers for maintaining stability, he or she usually has the outriggers on the snow and has downward force on them. This has the effect of taking weight off the ski which makes it slightly easier to initiate the steering turn, but also has the effect of reducing edge contact with the snow. While skiing, the skier appears to be relatively static. Some of this rigidity is the result of the skier leaning and reaching forward. This body position prevents the skier from bending significantly in a ) or ( shape at his or her side to create angulation.
All in all, Static Monoskiing is functionally limited in both speed and turning control. Overall speed is reduced due to skid turns that scrub off speed. Control is less while on a flat ski which tends to be bouncy at higher speeds as it launches into the air as it hits bumps. The turns are more fan shaped which also creates more bumping up and down as the ski sweeps the slope. This sweeping motion also makes it more likely for the static skier to catch a downhill edge. Static skiers tend to lean up the hill as opposed to angulating down the hill. The skier’s head and shoulders are usually pointed in the direction of the ski as opposed to down the hill. There is minimal upper-body and lower-body separation during Static Monoskiing.
Dynamic Monoskiing
Dynamic Monoskiing is a much higher and more difficult level. It takes a lot of practice to perform. Dynamic Monoskiing allows for much greater control and faster speeds. It also incorporates Static Monoskiing when desired. Therefore, can be thought of as having two dimensions, whereas Static Monoskiing is only one dimensional. Here is how it works.
Dynamic Monoskiing is based around edging and arcing the ski to create carved turns. A carved turn uses the side cut of the ski to slice a turn through the slope. The radius of the turn is proportional to the degree of ski side cut. Greater side cut leads to a smaller radius turn. In addition, when the ski is flexed into an arc, it has the effect of increasing the side cut and shorting the radius of the turn. The greater the angle of the ski edging, the greater the forces that bend/arc the ski.
When the ski is edging into the slope and not skidding, the force of the skiers momentum is driving the ski deeper into the slope. The ski is cutting through the snow. As it carves the turn, energy is not lost to skidding and snow-throws. Therefore, speed is maintained. The smaller the radius of the turn, the greater the skier's angular momentum which creates a force which "pushes" the skier to fall "outside" the turn down the hill. The skier adds to this force angulating his/her body down the hill. Counter acting this force is the force of gravity which is pulling the skier to fall over up the hill as the ski is edged.
In order for the ski to be edged, the skier must lean his/her monoski up the hill. More uphill leaning angle creates increased edging. But more leaning requires more upper body angulation down the hill to keep the center of mass over the edge of the ski.
A "perfect" carved turn is created when the gravitational force of falling up the hill is in balance with the angular momentum force to fall down the hill and the ski is on its maximum edge and the ski itself is at bent to its maximum arc. In this case, the ski slices through the shortest radius turn.
The radius of this turn is dependent upon the skier's speed and weight, his/her ability to edge and angulate the ski, the consistency of the snow, the side cut of the ski, the quality of the ski's edge, the flex of the ski, and the angle of the slope. When the ski is on edge and cutting through the snow, it is less bouncy because it is slicing through the slope. The ski's edge is on constant contact with the snow. This creates a smoother ride for the skier. This smooth ride translates in the skier’s ability to ski faster. Therefore, not only is no energy lost from skidding, the edged ski itself creates a better suspension system for the monoski.
A bouncing ski causes less control in the same way a sled bounces around as it careens down the slope. A flat ski is effectively a sled. An edged ski is like a train wheel that cuts its own groove to ride in. As long as the ski stays in the groove, turning balance/harmony is maintained.
When the ski has been flexed to its maximum, there is a tremendous amount of energy stored into the ski and monoski suspension system from momentum. The skier can use the release of this energy to help create the next linked turn. As the ski straightens out, it initiates the process of the opposite turn. In this case, turns are linked S's as opposed to Z's. There is minimal time that the ski is straight and flat. The ski transitions from edge to edge which is also turn to turn.
Since the skier is able to maintain higher speed and control, the skier is able to keep the monoski pointed mostly down the hill. What this means is that the skier is moving back and forth within a narrow orientation relative to the slope fall line. The skier doesn't make turns that orient him/her perpendicular to the fall line (towards the side of the slope). Think of a windshield wiper that is sweeping back and forth on a tall but narrow windshield.
When the monoski is orientated down the hill, it's turns are shallower. Shallower turns make it more stable and less likely to fall to either side because the ski doesn't skid or slip unexpectedly creating an unexpected loss of balance. There is less uphill leaning pressure on the ski edge, so it is less likely to slip on an icy slope. But the existing edging also makes catching a downhill edge less likely. Shallow carved turns require less edging angle since angular momentum is less and the skier is able to maintain his/her center of balance over the ski with less body angulation. Therefore, "perfect" linked turns are the result of following the fall line down the hill, ski and suspension pressure and release which creates back and forth edging/turning that carves through the slope. These turns will also be symmetrical on an even slope.
The key to Dynamic Monoskiing is the ability to create angulation combined with the ability to balance the ski on its edge through a turn. Greater angulation ability leads to shorter carved turning radiuses with higher degrees of edging which leads to greater overall speed and control.
The ability to angulate is a function of muscular body control. More body control leads to greater angulation. The ability to balance on an edge is also a function of muscular body control combined with lots of practice. The more body control the skier has the easier it is for him/her to learn to balance on an edged ski.
The less body control the skier has, the less angulation that can be created due to seating and upper body support systems such as high seat backs, chest straps, and shoulder harnesses. The less body control the skier has, the greater amount of time it takes the skier to learn to balance on an edged ski. The reason for this is that the skier has less muscular control to balance the monoski AND he/she must also learn to balance his or her upper body in conjunction with balancing the monoski. Tight rope walkers use long poles as a means to increase their ability to control their weight distribution and body control.
A person with a high SCI injury has no direct muscular connection to the monoski. The body to ski connection is made through a minimally controlled upper body which tends to be unstable and bounce around. When balance control of the skier's upper body is lost, so is balance control of the edged ski lost. Or the skier's upper body is so constricted so that angulation ability is low.
The monoskier with a higher-level injury (or less upper body control) will try to compensate for his or less upper body instability by learning forward and using his/her outriggers to create a more stable tripod shape. This body position will result in further loss of angulation ability. Angulation ability is gained when the monoskiers arms and shoulders start neutral and NOT forward with minimal to no weight on the outriggers. But this position is less stable for a higher-level injury creating an inherent desire to learn forward and balance with the outriggers to increase stability.
A monoskier with low-level trunk/body (low-level SCI, amputee, etc) control is like the tight rope walker with a long pole. It takes him or her less time to learn to balance the monoski on its edge. He/she has a greater ability to correct mistakes. A monoskier with a high-level injury is like a tight rope walker with no pole who must also balance his or her torso on the tight rope. There is minimal room for error and less ability to correct a mistake and not fall.
As a result, most monoskiers with high level SCI (or similar) are likely to engage in Static Mnoskiing. It takes high SCI skiers extensive practice and proper instruction advance to Dynamic Monoskiing.
On the other hand, due to the reasons stated above, for monoskiers with lower trunk body control, Dynamic Monoskiing is the natural progression from Static Monoskiing with sufficient time and practice. Where Dynamic Monoskiing is a linear advancement for low trunk/body control monoskiers, high level Dynamic Monoskiing is more like a quantum leap for monoskiers with minimal trunk control.
Related Posts: Monoskiing - The Dynamics and Psychology of Falling
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