by h.harb » Wed Jan 28, 2004 11:58 am
OK, you roped me into this one, there is so much confusion and misinformation about this aspect of balance that I hardly know where to begin addressing this issue. Here's a try.
For/Aft balance conclusions:
Our attempts to find solutions for aligning and correcting for/aft balance are extensive. We did a number of tests with skiers numbering as large as groups of ten with varying body types, men and women. We measured, changed ramp angles, and forward lean in the same boots. We measured all of their leg lengths, femur, tibia, and torso proportions. This involves considerable time and effort, so I speak confidently becasue this is scientific research and it included ligitimate PhD?s as particpants.
Binding placement:
We did tests with binding placement. From this test we found Austrian skis ski better with more forward binding placement then the manufacturers recommend.
Overall, we learned more about where skiers prefer to stand based on their body proportions, but we also found that joints and movement capabilities for these joints are so extensive that actual concrete conclusions are difficult to nail down. This is not as simple as lateral canting. Here is some advice I can offer:
The first step in the process is naturally boot selection. Changing from one boot type, design or brand can actually correct the problem immediately. Some skiers are more likely to have for/aft balance problems than others and they are fairly easy to recognize because they demonstrate very little ankle movement capability in their boots.
When you ask them to flex the boot they will try to flex by moving their rear end up and down, rather than pulling back the feet and lifting and moving the hips forward to bring the mass over the boot to flex the plastic. Skiers often confuse moving forward while skiing as an up movement, which by the way is still taught by most instructors. Modern skiing has no purposeful up movements. The movements used by the best skiers are either extension or flexion and the extension is always at an angle to the slope, rarely vertical. The other movement of course is flexion or bending. This is also done at an angle to the slope not when the body is vertical to the flat surface at the base.
Boots:
Please remember that we have no interest in degrading a boot company as they all go through design cycles. I don?t need twenty phone calls from the sales reps asking me why I don?t like their company. The comments I make here are based on actual results and what we see and evaluate on snow with skiers we ski with and the difference we make with the skiers when we change their products. I always keep in mind that these companies can reverse themselves with their product the very next season, as many have done.
Nordica?s are notoriously difficult to stay forward in, especially the last versions of the grand prix model. Others that can be problematic are Lange, Dolomite and Tecnica.
Our testing has demonstrated that Salomon, Dalbello, and Head do a very good job of helping skiers stay centered.
Physical limitations such as dori-flexion (range of motion of the ankle joint in for/aft movement) will cause severe for/aft balance problems for about twenty percent of skiers.
On snow exercises are helpful for developing awareness of proper stance range, but they don?t necessarily solve the problem permanently. A combination of good boots, heel lift, inside and out of the boot (under the binding) and proper coaching can definitely change how skiers stand and can be effective long term.
The balance program needs to be integrated and coordinated by a good coach and preferably the coach is involved with the equipment selection and changes. There are few of these coaches in the ski industry and I have yet to meet one from Europe.
I have been an advocate of this kind of approach for over ten years, but the instructor organizations and ski equipment sellers have not seen fit to organize and bring this kind of education to the sales people or this service to skiers. If few are actually taking responsibility for the content and results of a ski lesson or equipment sale then there will always be opportunity for less then optimal results.