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POSTED IN 01/10
JOE BOUSCAREN, M.D.
Contributing Editor
Joe is a sports medicine physician, world class rower and national masters XC racer with multiple age group medals from masters nationals. He’s been going to the Silver Star B.C. Thanksgiving camps for ten years, the last five as a LSD coach. He’s a level 2 NENSA coach and has a special interest in the physiology and biomechanics of endurance sports performance. He was on the Boston Celtics medical team and did physiologic testing for the Celtics, National rowing team, college XC and rowing teams and individual members of the US X-C and biathlon teams. www.skifast.us JBouscaren@comcast.net
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Cross-country skiing is one of three quadripedal sports (xc skiing, rowing and swimming) but is unique in that cross-country athletes must modify their technique and power output to accommodate hills, flats and downhills.
Striking the right balance between high power output and speed, and low power output and recovery will produce an optimal race result.
The basic skating techniques are single stick (gliding herringbone), V1, V2, V2 alternate, skating without poles and tucking. At least 14 distinct skating techniques can be identified when adding shallow joint angle, whole body falling forward body positions and the jump skate variants to the mentioned basic skating techniques.
In reality the number of skating techniques is almost as infinite as terrain, speed and snow conditions dictate small changes in body position, technique, power output and timing.
By fluidly and constantly adjusting: joint angles, the number and amplitude of moving parts, the frequency of movement, the amount of upper body versus lower body work and the level of relaxation in the legs when gliding, your skating technique will become as efficient as an automobile with a constantly variable transmission.
Shallow knee and hip joint angles with a whole body and hips forward body position.
Moderate to deep dorsiflexion of the ankle allows the skier to stand up straighter in the knees and hips while still maintaining a forward body and hip position. This has two major advantages: 1) you are supporting the majority of your body weight through your skeleton while allowing the quadriceps and gluteal muscles to relax and 2) your body is in a falling forward position which can only be maintained by taking another small skating step, this is free power supplied by gravity!
Deeper knee and hip flexion with a hips neutral starting position can be used when more power and speed is required.
Fewer moving parts or smaller amplitude of movement saves energy.
The extreme example of this is the tuck, no moving parts! By applying numbers 1 and 2 together you get the extremely efficient high tuck. Use V2 alternate over V2 when you can; by only poling on one side you save the energy of the second pole plant.
Another example is shifting to V2 instead of V1. With V1 you are loading the muscles for a long time and moving in a larger amplitude pattern; V2 has lower amplitude of movement and more gliding and is more efficient as long as the steepness of the hill does not cause you to overload your muscle strength.
Again, when trying to go fast in a sprint, higher amplitude movements are needed.
Use a lower frequency of movement when terrain allows, but a higher frequency, smaller step, skating style saves muscle power on prolonged uphills.
The German world cup skiers are popularizing a very upright skating technique, which when performed with a higher frequency, smaller skating “step” style, is very resting on long moderate uphills. In flatter and downhill sections, gliding as much as you can (without allowing the ski to slow down too much), lowers the frequency of movement and saves energy.
Balance lower and upper body power output.
Attacking a steep hill with V1 technique often puts the skater’s upper body almost parallel to the hill as a large percentage of the skier’s weight is transferred to the poles and off the legs. This off-loads the legs under this most power demanding condition, and saves the leg and hip musculature for the remainder of the race.
Adding more poling power to your V2 expands the terrain over which you can apply this efficient technique. Train and work the arms aggressively in training and racing, this spreads out the work over the whole body and prevents our main power producers, the legs, from failing. If the legs do fail towards the end of a skate race, double pole as best you can until the legs recover some!
Completely relax your legs when balancing and gliding.
The best skiers are almost like magicians on snow. They can balance and perform difficult movements on snow while gliding with almost complete relaxation! This saves a lot of wasted energy.
Most skiers are not good enough when balancing on one gliding ski over changing terrain. When your legs, hips and balancing muscles are tight while gliding, it is like driving your car with the brakes on. You are using much more energy than needed to achieve a given speed.
While these adjustments may come easily to very talented skiers who spend a lot of time on snow, they are worth thinking about and constantly experimenting with during long training sessions.
Adopting the right body positions and techniques, quickly and easily, will end up saving you a lot of energy; you will generate more “free” (gravitational) speed and get better race results!
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