The midsole determines the stiffness of a boot and also provides cushioning and shock absorbency. While you may think that a stiff boot sounds uncomfortable, just remember that long hikes and moving across rocky or uneven terrain is torturous with a flexible boot as your feet feel and flex around every stump, root, rock, and hillock. Therefore, a stiff boot definitely keeps you more comfortable long-term, provides a higher degree of support, and helps keep your feet healthy.
Ethylene vinyl acetate, or EVA, is among the most common choices for midsole construction. It is budget-friendly but still provides plenty of cushioning. To increase stiffness and support, extra layers of EVA are used for a firmer feel around key areas like the forefoot. This high-density foam also offers a high degree of shock absorption.
Polyurethane lasts longer than EVA, is firmer, and gives more support. It is most commonly used in the midsoles of high-end backpacking and mountaineering boots. This material is more durable but costs more than EVA.
Multi-layered Gore-Tex is often used as a lining material. This technologically advanced fabric creates a dry environment inside your boots by wicking moisture or perspiration away from your feet and socks to the exterior. It also stops moisture penetrating the boot from the outside. This is a great choice for warm-weather boots as it offers a high degree of breathability and maintains a dry environment even when your feet are sweaty. You’ll also find insulated Gore-Tex liners in cold weather boots that trap body heat while still drawing away moisture.
Many hiking boots and the majority of backpacking boots feature internal support structures. These generally increase support and offer protection against terrain and obstacles.
Walking boot shanks are plastic or metal strips that sit between the outsole and the midsole. Shanks offer support and shape the boots’ arch. These inserts are generally between 3 and 5 millimeters thick and their presence adds load-bearing stiffness to the boot. Some boots have shanks that run the entire length of the midsole while others have a three-quarter or half-length shank.
Plates are important if you expect to be faced with really rough terrain. These thin, tough plates are semi-flexible and sit between the midsole and the outsole and offer protection against bruising from uneven ground.
Choosing the right outsoles is important, as they determine traction, stability, and, to some degree, support and load-bearing capability.
The lugs or the tread of the boots is crucial to safety and support. Look for deep, thick lugs like those on the Salomon Quest 4D 2 GTX that we reviewed, as these maximize grip and provide optimal support, even for those bearing heavy loads. Make sure the tread or lug pattern is widely spaced as this ensures stability and a high level of traction. A wide-spaced tread pattern also provides a self-cleaning feature, as the treads are able to shed mud and debris as they flex with your footsteps.
The heel brake is a distinct tread pattern. Clearly defined, the heel zone is separate from the forefoot and arch. This increases traction when faced with slopes.
Carbon rubber has been chemically altered from its natural state and has had carbon added. This enhanced rubber is the most popular material for walking boot outsole construction due to its improved performance and comparatively low cost. It is lighter, more robust, and offers a higher degree of shock absorption than natural rubber.
The insole is the layer that’s in direct contact with your foot. It provides a cushion between the midsole and your body. Usually removable, insoles are crucial to your comfort. However, because they are removable, if you find that your insoles wear out or aren’t terribly comfortable for the shape of your feet or arches, you can simply purchase and insert new insoles. Look for features like extra shock-resistance, pressure relief, and anti-microbial or anti-fungal properties.
That’s it. Everything you need to know to fit and buy the right boots. Soon, we’ll be adding walking boot care advice, and some reviews of our preferred walking boots, work boots for the homestead, and bugging out boots. If you’ve got something you’d like to add to this guide, please do let us know in the comments.
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