125 Intro to bumps
There are many skiers and snowboarders who are under that mistaken assumption that the only way to succeed in the bumps is to master the short turn. Some believe that in order to improve in bumps they need to beat themselves up over and over again. In truth, bumps don’t actually exist if the rider/skier has a truly effective suspension system. This is a polite way of saying that if the athlete can maintain board/snow contact regardless of surface contour, bumps are no big deal.
This assumes, however, that the rider in question is using the equipment effectively, rather than just pivoting from one turn to the other.
Unfortunately, most riders who think they have any business riding bumps create turns by using what is referred to as ‘cross-under with a kick’. At the end of each turn, the board begins to move under the rider, at which point it is pivoted in the direction of the next turn. The problem here is manifold: the board is pivoted across its direction of travel for each turn, a problem in rough terrain as the board needs to swing unimpeded. Rotational movements require secure footing to initiate, and complete. Secure footing is hard to come by amidst moguls. At the same time, the board is edged, by pushing it away from the body, until a platform has been created. Again, this is a sketchy proposition on anything other than a flat surface.
So, if turn mechanics are one issue, the second issue is the influence of leg flexion/extension on the angle of incidence between board and snow. More often than not, most boards are set up such that when a rider bends their legs, they wind up tipping the board in one direction or the other, unless they take great pains not to, by involving greater articulations of the hip and ankle joints. In the bump context, this means that the edge angle will rise and fall with the bending of the legs, again, not necessarily desirable on an uneven surface, given the fact that for each turn the angle of the board to snow should rise and fall more or less evenly. Since the contour of the average mogul field will affect the angle of incidence between board and snow even if the rider is not actually turning, the edging of the board should be independent of all other movements.
Lastly, there is the concept of pressure distribution along the length of the board. As stated previously, if too much weight is applied to the front foot in a turn, the board will skid, and if too much is applied to the tail of the board, the board will not turn (much). This is largely a binding location thing. On a relatively smooth surface, it is possible to adjust, for a time, to incorrectly located bindings, the only tradeoff being muscle fatigue. Bend the front knee a little more, and stand more on the rear foot (if the clamps are set too far forward). However, if the knees have been bent to even out weight distribution, bending them more or straightening them will have a possibly negative effect on pressure distribution. Thus, the legs cannot function as a suspension because they have already been used for something else.