Flex adjustment

The stiffness of a ski boot - its resistance as you press against the tongue - varies with the design of the boot, the material from which it's made, and how tightly it's buckled. Some boots provide no mechanism for adjusting their flex; others do. A flex adjustment allows the boot's stiffness to be modified independently of its fit. This is beneficial for numerous reasons. Skiers come in many bodyweights for the same size foot - a slim, willowy skier may want a softer boot, while a sturdy, muscular skier may require a stiffer boot for adequate support. Skier preference varies greatly - some skiers like a stiff boot, while others prefer a larger range of flexion. Ski boots, made of plastic, change stiffness as a result of outdoor temperature. When the plastic is warm, as on a spring day or in the shop, the boots will be quite soft - they will flex more easily and farther. When the plastic is cold, on an early winter morning, the boots will be much stiffer, and will flex less. A flex adjustment allows the same boot to provide adequate, pleasing performance to a variety of skiers, under a variety of conditions.