Movement Analysis in More Detail
Recording: Record a video of your student’s skiing session or your own, and then review the footage. Pay special attention to the ‘what-how-when’ during all phases: propulsion (or push-off), weight transfer, and glide. When recording, it’s helpful to have a specific focus in mind. Utilizing slow-motion can offer deeper insights. Depending on your focus, film from the side, front, back, or consider capturing all angles.
Observe and Focus on Specifics: Examine body positions, movements, their timing, and the power application of the skier’s movements as well as skis and poles throughout each phase. If you’re uncertain about what to observe, begin with straightforward yes-or-no questions. Examples of such questions, from addressing beginner skier to expert skier :
- Did the opposing arm and leg move forward simultaneously in the diagonal stride?
- Did both skis of the sit-ski maintain contact with the snow on the turn?
- What was the angle of the ankle flexion during the glide phase?
- Did the ski touch the snow before one foot passed the other in diagonal stride?
- In the V1, did both poles make contact with the snow at the same time as one ski during recreational skiing?
- In the V1 bounding, was the time gap between the athlete’s foot landing and the pole push too long, affecting the efficiency of forward movement?
- Was the strength of the pole push proportionate to the strength of the leg push in the given context?
Tips:
● Your aim is to identify consistent patterns rather than isolated moments of mistakes or excellence.
● Keep in mind that the movement analysis for standing skiers and those with physical disabilities, including sit skiers, is consistent for the body parts that are accessible and in use.
● It might seem a bit odd to make notes when everything seems perfect with the skier. However, remember that the goal is to carefully evaluate the skier’s body position, movements, timing, coordination, and how they apply these skills to their skiing techniques. This systematic approach helps us spot areas where there might be room for improvement or ensures that the skier is executing the task as instructed. So, even if you’re using movement analysis to check if the skier has incorporated previous feedback and is following the task’s guidelines, it’s a valid and valuable application of this approach.
● Video recording can be incredibly beneficial if you have the means to quickly record the skier using a phone or tablet. It lets you slow down the skiing action and go over different phases with the student. When you review the video, just keep the feedback constructive, not judgmental. While analyzing the video indoors has its place, the best feedback for a skier is the kind they can use right away to practice and improve.
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What to observe and note:
- Body Position & Movements:
- During each skiing phase, examine the body’s position and its forward tilt. For standing skiers, focus on the angle at the ankle, knee and hip joints, and for sit skiers, concentrate on the hip joint.
- Center of mass in relation to the base of support. For standing skiers, this base is their feet. For sit skiers, it’s the range between the front and back attachment points on the sit-ski frame.
- Hip positioning and movement.
- Shoulder alignment and movement.
- Lower Body Action:
- Weight transfer from one ski to the other.
- Leg extension during push-off.
- Range of motion in the ankle, knee and hip joints.
- Upper Body Action:
- Synchronization of arm and leg/lower body movements.
- Poling technique, including pole plant and push-off.
- Arm swing.
- Rotation and lean of the trunk for turns and direction changes.
- Foot Action:
- Foot placement when transferring weight from ski to ski, specifically considering how much it moves past the other foot before bearing the full weight.
- Foot placement when gliding.
- Balance & Stability:
- Maintenance of balance during glide phases.
- Stability during weight transfers and turns.
- For sit skiers, balance involves both core stability and equipment management.
- Trunk Stability and Mobility (in sit skiing):
- Observe the sit skier’s ability to stabilize their trunk in the sit ski that is used for ensuring efficient power transfer.
- Look at the sit skier’s ability to rotate and lean the trunk for turns and direction changes.
- Equipment Interaction with the Snow:
- Ski edging of the ski in skate skiing or during turns.
- Ski grip zone’s effectiveness during classic skiing.
- Ski-to-snow contact.
- Ski glide length.
- Pole length and angle relative to the snow during poling.
- For sit skiers, evaluate the fit and function of the bucket (the seat in the sit ski) and the support it provides for optimal movement.
- For sit skiers, pole use is crucial for both propulsion and steering.
- Timing & Rhythm:
- Coordination and timing of arm and leg movements.
- Rhythm maintained during various techniques like the V1, V2, and diagonal stride and during transitions.
- Breathing & Stamina:
- Breathing patterns relative to skiing rhythm.
- Endurance and pacing, especially in longer races.
- Transitions & Techniques:
- Switching between different skiing techniques, e.g., from double poling to diagonal stride.
- Technique selection based on terrain and conditions.
- Observe how the sit skier initiates and completes turns. For some sit skiers, this may involve a combination of upper body movements and equipment adaptations.
Identify Inconsistencies: Compare your student’s ski and pole actions, body position, movements, and their timing to the standards of optimal skiing. For skis, this involves contact with the snow, edging, flattening, and turning. For poles, it’s about their contact with the snow.
Set Targets: Based on observations, set specific improvement targets. Instead of broad goals like “improve glide,” aim for more specific ones such as “keep the body more upright during the glide phase.” Be clear about desired adjustments in terms of body position, movement, and timing as well as the goal of those adjustments.
Practice with Intent: After identifying areas of improvement and outlining actionable steps for your student, head to the trails together with a focused plan to work on these specific areas. This deliberate approach can lead to more focused practice sessions.
Consistent Analysis: Improvement is a continuous journey. Regularly record and analyze skiing sessions, noting progress and any new areas that might need attention. Immediate feedback accelerates improvement. Once you’ve assessed your student’s performance, implement changes and let them try again.
Use Technology: There are apps and software available that can break down videos into slow motion, compare side-by-side with professional skiers, or provide biomechanical analysis.
Reflect and Adjust: After each session, reflect on the changes your student made and their effects. Based on this reflection, help your skier create new goals and a pathway for attaining them.
The Role of Effective Movement Analysis
This article delves deeply into movement analysis because it’s a complex subject. Yet, in reality, you often have only a few minutes, or even just one minute, to use it with a student. That’s why it’s vital to become really good at it. If you’re inaccurate or it takes too long, your teaching won’t be effective.
In essence, while movement analysis isn’t a standalone lesson or training session, it’s an essential skill in the coaching toolkit, guiding both the instructor and student towards more efficient, or closer to optimal, skiing. Instructors and coaches who invest time in honing this skill not only elevate their teaching abilities but also become better skiers themselves. The path to proficiency in cross country skiing, whether as a learner or an instructor, runs through effective and diligent movement analysis.
About the author:
Marcin (Martin) Wiesiolek is a seasoned ski instructor with expertise in cross country, Alpine, and adaptive skiing. He lives in Grand Junction, Colorado.
A special thank you to Scotty McGee for content editing. Scotty instructs and guides in cross country, telemark, and Alpine skiing in Jackson, Wyoming. He’s also a four-time member of the Professional Ski Instructors of America National Nordic Team.