Learn sideslipping honestly: prerequisites, five stages from the first edge release to the edge set, and the mistake that makes you fall uphill.
Sideslipping means: you stand across the slope, release your edges a little and slide sideways down the hill with both skis at the same time. By edging again you stop. You are not skiing, you are dosing – and that is edge control in its purest form.
Why do you need it? Because every slope eventually looks steeper than expected. Then sideslipping is the way down without turning and without speed. The German Ski Instructors' Association therefore lists "traversing and sideslipping" as its own learning goal at level Blue, after the wedge turns [2].
The physics behind it is surprisingly sober: a snow-machining model describes fall-line sideslipping, traversing with sideways slipping and the hockey stop, and agrees with skiing practice [1]. In plain words: your edge pushes snow away, and how much is decided by your edge angle.
How hard is it? The basic form usually works after one or two practice mornings. Slipping evenly, also diagonally, and stopping cleanly takes longer from experience – there are no reliable learning-time studies.
Stand across the slope, both skis parallel, shoulder-width. Tilt knees and ankles slightly uphill: the uphill edges bite and you stand firmly. Your upper body hangs slightly downhill over the skis, not uphill. Milestone: you stand ten seconds calmly on the uphill edges without slipping.
Now slowly tilt knees and ankles downhill until the edges just stop gripping. The skis start sliding but stay across the slope. Weight rather on the downhill ski. Milestone: you release the edge, slide one metre and stop by tilting back – five times cleanly.
The more you release the edges, the faster you slide. Tilting back slows you down. You look for the middle: even, not jerky. Milestone: you slide 10 metres in a strip about one ski length wide without drifting forward or backward.
Turn the tips slightly downhill so you also move forward a bit while sliding. The trick: edge angle and ski direction together decide the track. Milestone: you slide 15 metres diagonally to the right and to the left without losing direction.
While sliding, tilt the knees uphill and set the edges softly, not hard. The stop should feel like braking on snow, not like hitting a wall. Milestone: you stop out of the slide without the skis catching or you tipping uphill.
Sideslipping is about edges – and edges are exactly what is involved in cruciate ligament tears. The video analysis of 20 World Cup cruciate tears shows: in half of the cases (10 out of 20) the skier lost pressure on the outer ski, the inside edge suddenly grabbed and the knee twisted inward [3]. That is racing, not sideslipping – the lesson still holds: set edges softly, never jerkily.
The knee is the most common injury site in skiing: 27 to 41 percent of all injuries depending on the survey [5] – roughly one in three to four. In a case-control study of 392 injured recreational skiers, ice (OR 12.4), grippy snow (OR 7.8) and fresh snow (OR 10.5) were associated with a cruciate tear [4] – a more than twelvefold higher chance with ice. That does not prove a link to sideslipping. But it is a reason to practise on soft, groomed snow and not on ice.
Also: slide only where nobody is below you and look uphill and downhill before you start [6]. Hold the poles loosely: a pole grip held in a fall can cause "skier's thumb" [5]. And do not overrate yourself: in a study of 62 people, recreational skiers rated their carving on average 1.71 points higher than a sensor did [7]. This guide explains and motivates, but does not replace a ski instructor – and sideslipping off-piste does not replace avalanche training.
Turn around after ten metres and read your track. A clean slip track is a flat, even, smooth band. A furrow with a sharp edge means you caught an edge. A track running diagonally down means your skis were not across. The snow tells you at once what you did wrong – louder than any coach.
Stand across the slope and slowly tilt knees and ankles downhill until the edges stop gripping. The skis slide but stay across. Tilt the knees uphill again, the edges grip and you stop. You control everything with the edge angle [1].
When the slope is steeper than expected, when you do not want to turn in a narrow passage, or when you must descend in a controlled way after a fall. As a learning goal it comes after the wedge turns in the teaching plan [2]. It is not a trick, it is your emergency exit.
Usually the edge angle is too large (the edges grip too early) or your upper body hangs uphill. Tilt the knees more carefully downhill, bring the upper body over the downhill ski and look downhill. On ice it gets harder – choose soft snow.
Done cleanly and slowly it is a basic technique. Risky is a sudden, hard edge grip: in World Cup video analysis that was the most common mechanism in cruciate tears [3]. So always set the edges softly and practise on groomed snow, not on ice [4].
On a wide, moderately inclined, freshly groomed slope with free space below you. Soft snow forgives mistakes more than ice [4]. Start with a few metres, then extend the distance. An instructor can show you how much edge is enough.
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