Ski boots

Ski boots are footwear used in skiing to provide a way to attach the skier to skis using ski bindings. The ski/boot/binding combination is used to effectively transmit control inputs from the skier's legs to the snow.

Ski boots were leather winter boots, held to the ski with leather straps. As skiing became more specialized, so too did ski boots, leading to the splitting of designs between those for alpine skiing and cross-country skiing.

Modern skiing developed as an all-round sport with uphill, downhill and cross-country portions. The introduction of the cable binding started a parallel evolution of binding and boot. The binding looped a strap around the back of the boot to hold it forward into a metal cup at the toe. Boots with the sole extended rearward to produce a flange for the cable to firmly latch to become common, as did designs with semi-circular indentations on the heel for the same purpose.

Effective cross-country skiing requires the boot to flex forward to allow a striding action, so the boots were designed around a sole piece that allowed forward flexing while still keeping the foot relatively firm side-to-side. The upper portions, the cuff, was relatively soft, designed primarily for comfort and warmth. Modern cross-country ski boots remain almost unchanged since 1950s, although modern materials have replaced leather and other natural fibres.

With the introduction of ski lifts, the need for skiing to get to the top of the hill was eliminated, and a much stiffer design was preferred, providing better control over the ski when sliding downhill. A key development was the invention in 1928 of the Kandahar cable binding, which attached the heel solidly to the ski and used a strong spring to pull the boot forward into the toe iron. The design required a stiffer, reinforced boot sole, often build on a wooden shank. New boots that had been boiled in oil or soaked in glue were introduced to stiffen the upper cuff. These were universally uncomfortable, especially during the break-in period when they were new. Once broken-in, they wore out quickly as they continued to soften up. Racers typically had only weeks to wear a particular pair before it was no longer useful. Another attempt to stiffen the leg/ski connection was the "long thong", a long leather strap fixed directly to the ski that was wrapped several times around the lower leg and then buckled closed. This offered a great improvement in control, but increased the risk of injury in the event of an accident.

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Wikipedia