Ski Racing - January 16, 2012

LETTERS

Equipment-related solutions to the above scenarios are not very well understood, but my opinion that a longer ski with less sidecut will increase phantom foot injuries is reasonable. The implications cannot be responsibly dismissed or ignored without further investigations.

Conclusion
I believe the FIS is recklessly endangering
thousands of athletes participating in their
sanctioned events by irresponsibly ignoring
or dismissing large bodies of scientific evi-
dence, the opinions of many experts and the
gut instincts of the vast majority of coaches
and athletes. I believe that the FIS is forc-
ing the industry to spend tens of millions of
dollars to develop and manufacture skis that
may turn out to be too dangerous to use.
There are legal and moral consequences to
the new equipment rules. The rushed impo-
sition of the new rules should be carefully
reconsidered.
Sincerely,
David J. Dodge, BSME

1. Bere, Mechanism of ACL Injury in Skiers: Letter to the Editor, The Ameri-
can Journal of Sports Medicine
2. FIS ISS 2006-2011 SAFETY IN ALPINE SKI RACING
3. Bere, Mechanisms of Anterior Cruciate Ligament Injury in World Cup Al-
pine Skiing, The American Journal of Sports Medicine
4. Ettlinger CF, Johnson RJ, Shealy JE, The Prevention of Knee and Lower
Leg Injuries Among Elite Alpine Skiers and Competitors.
5. Ettlinger CF, Johnson RJ, Shealy JE. A method to help reduce the risk of
serious knee sprains incurred in alpine skiing. Am J Sports Med.
1995; 23: 531-537.

Appendix: A discussion of biased assumptions. The quotes below represent some of the assumptions that are the foundation on which FIS built its “proof” that the new equipment rules will reduce injuries.

• “In this out-of-balance position, it is reasonable to believe that carving skis may catch the edge more easily than older skis”.1

• “Problems with current equipment in terms of safety according to expert opinions: • Equipment is too aggressive • Equipment is too direct in force transmission • Equipment has too strong self steering behavior • Equipment is difficult to control • Equipment is difficult to get from the edge • Equipment allows too high edge angles”. 2

• “This loading pattern is related to the carving ski’s self-steering effect”. 3

• “With aggressively carving skis and ag-
gressive snow conditions, large forces are
generated when the inside edge catches the
snow surface”. 3
A set of less biased assumptions could
be:

• Without edge grip control is impossible — more control is good.

• Without a self-steering effect, control is impossible — more control is better.

• Athletes will use the tail of the ski whether
the ski has a large radius or a short radius
— without a tail balance is impossible.

A more reasonable set of conclusions might be:

• Safer skis should discourage skiers from taking body positions known to lead to injury.

• Safer skis should have linear responses to control inputs • Aggressive skis = Skis that are too sensitive and/or have non-linear responses to control inputs.