Saturday, September 12, 2015

Hip control, a grey area for many skiers?


Compare the two photos, one of  Mario Matt, he is one of the best slalom skiers of all time. Mario was twice World Champion. And here is a photo of a very good junior racer. The place in the turn isn't exactly identical, but for the purposes of describing this relationship, the photos are excellent.



This is a treatise of movement, technique and boot relationships based on set up and alignment.



At first glance these two skiers are similar. even some of the Check Points, hands, shoulders angle,  are easy to confuse. When you start to do a break down analysis, you start to see some discrepancies between the two. Let's take this one step at a time.

The most obvious is the inside hip position. Matt shows an inside, high hip. Our junior shows a dropped lower inside hip. Matt shows proper counter-acting of the hip and shoulders. Our junior has advanced the outside hip arm and shoulder.
The next most obvious observation is the outside ski. Matt's skis are at the same angle and headed in the same direction. Our junior's skis are at different angles and headed in different directions.

Let's see what is causing this and how is it fixed, so you can come closer to skiing like Matt?






I'll preface this movement analysis by saying our junior racer may not be making this same turn in every gate, this is a one time situation for this particular turn, so this is an exercise in skiing analysis for this turn only.



To find the causes you have to address a number of areas. First is physical preparation and physical maturity. It's not fair to compare Matt who is 35, to a junior, as far as strength and physical maturity. The bend in the waist and folding at the mid body can be due to core strength. These are big angles, speed and forces, so core strength has to be considered.



Going along with core strength idea is the issue of fore/aft balance. Matt is very centered on his skis, his torso is slightly forward, and his hips are forward over and directly above his boots. Letting the hips drop back too early in the arc, requires more edge angle to get the ski to shorten the arc.



When the hips go back or are dropped, the skis don't turn or arc as quickly, so some outside greater turning forces has to be applied. This usually involves the upper body and leg to give the ski a twist or pivot.

To reduce this hip drop situation a lateral movement component that relates to core strength needs to be  addressed, however is rarely done in training or in exercises. This involves the functional use of the muscles that pull the lateral part of your hip, toward the  bottom and side of your rib cage. In this video (below), the lines and graphics are drawn in to show the movements. They show as still frames, in the skiing run after the introduction. The lines and arrows show how the torso is to be moved using the muscles that pull the hip up on one side and the rib cage down on the opposite side.
               The graphics shown in the still frames of this video demonstrate the movements involved.


Muscles Engaged

Joint movements: lumbar lateral flexion
Lumbar lateral flexion is the sideways movement of the thorax toward the pelvis.
Muscles most involved in joint movements: quadratus lumborum, rectus abdominis, external oblique, and erector spinae (on one side) and internal oblique
There are 3 to 4 muscles in  combination that create this movement, most are deep muscles that create the side pull of the torso to the top of the pelvis. 

In the Mario Matt photo, the outside hip is also held back to create counter acting, while the torso is pulled down. I will elaborate about the rotational and torso tilting combination of muscles for achieving these movement in a different post. 

                                                             Serratus Posterior


Training and muscle awareness:
In dryland exercises try to make your skiers aware of these movements and the muscles that active the torso to the hip relationship. Few skiers realize that this is an important part of skiing. In another post I'll present exercises and movements to develop hip, to torso awareness.

Boot set up:

Boot adjustments can also have a huge influence in this case. Common boot situations like out of alignment, in tow areas,  can be a consequence of this slight tail push. We see this in our junior racer photo. For example: too strong a cuff set up toward the inside of the leg or over or too strong sole canting. Over canting makes the ski grip, run forward, but not arc, so the twist is necessary to quicken the arc and radius, but it's a skid. Often the upper body helps this along with some torso rotation.

What to do first? From a skiing persecutive and a boot perspective our approach would be to do a boot measurement series or refinement, and also work on the skier's fore/aft movements. Go to the source, instead of fixing the most obvious movements, which are only a compensations. Use a series of Fore/aft exercises. Fore/aft coaching is well documented in our "Essentials of Skiing" series, which comes in both video and book formats available on our www.harbskisystems.com web site.


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