News / Outsiders

What’s Inside a Hiking Shoe?

So many adventures, so little time … so many hiking boot choices!
At Merrell, we love the outside -- a passion won from many miles trekked: Across purple peaks to take in grand vistas. Over weeklong trips carrying packs that felt heavier with every trail sign we passed -- no matter how much food we ate to lessen the load. Up to the top for sunset and home in time for dinner, smaller-scale adventures: All of these satisfy our insatiable need for nature and motion.

From woolly bear caterpillars and staring down mountain goats to impromptu laughter with new friends on the trail, we get the ins and outs, ups and downs and highs and lows of hiking.

Let our experience guide you to find your ideal hiking shoe to do what you love outside.

THE TRAILHEAD – Start at the beginning

Every hiker and every trail is unique. To help you navigate choosing your ideal next pair of hiking shoes, we’ve packed insights from our collective adventures into this tutorial to give you some things to consider before you buy.

THE TRAIL: The Nature of Your Hiking Adventure

Hiking comes in many flavors. A burly boot is overkill if you’re into adrenaline and speed, but just the thing if you love multi-day treks to the summit with a heavy pack. Pick your passion below:

Backpacking - You log miles in on the trail for more than one day, sometimes a week…or more. You set up backcountry camps along the way and carry serious amounts of gear in a heavy pack (30lbs or greater). You have a topo map and a compass and are not afraid to use it.

Day Hike – You get up the mountain and back home in a single day, but the journey is at least five miles, includes elevation gain and you often carry a mid-weight pack (under 30lbs) with extra layers, first aid kit and food.

Quick Trip – Out for a couple of hours with family or friends, you enjoy taking in 0-5 miles that entails perhaps more talking than climbing, and carry a small pack with your snacks or lunch -- and a raincoat, just in case.

Speed Hike – You like to sweat, and your trail outings are your daily workout. You thought about going running, but that just didn’t fit the bill today. Your favorite things:  challenge, varied terrain, sports watches, energy gels and a water bottle carrier.

THE JOURNEY: Types of Hiking Boots and Shoes

In the end, the hiking shoe you choose is really a matter of personal preference and what feels the most comfortable. With an array of hiking shoes and boots in the Merrell line, we developed recommended uses for each type of shoe to help you identify your needs. Our footwear uses the FIST scale, which refers to how flexible to rigid a shoe is on a spectrum.


Light Hiking Shoes (FIST level 1-4) – At Merrell and the greater outdoor consumer world, these are often called multi-sport shoes. Sometimes resembling a really “teched-out” running shoe, these are ideal for a Social Trip or Day Hike. Specific Merrell styles that fit in to this category include: the Men’s Moab and the Women’s Siren.

Hiking Boots (FIST Level 6) - Available in a mid or high-cut (described below), hiking boots are usually a mid-weight product, sturdy enough for some time on the trail, but not so bulky that you feel weighted down. With solid lugged outsoles for traction, these support your feet and ankles when you carry a small pack via a partial rigid board, or shank, underfoot for support. Merrrell styles that fit in to this category include: the Chameleon (Men’s and Women’s), Women’s Calia and Men’s Geomorph.

Backpacking Boots (FIST Level 7-8) - Designed to carry a pack and to support heavy weight, these rugged beasts are steadfast through every element of your mountain challenge. Beefier mid or high cut backpacking boots provide ankle support and stability for carrying a heavy pack, with a full board for rigidity to support underfoot. To best tackle uneven, variable terrain, they use a heavily lugged outsole for traction. Merrell styles that fit in to this category include the Men’s Sawtooth or our Original Men’s Wilderness.


Some features you need some you might not. Try to find a hiking shoe or boot that has the best package of features to fit the type of hiking you most enjoy. Below we describe basic hiking boot features to prepare you

1. Boot Cut: How low should you go?

Low Cut – Great for travel, social trips and day hikes, low cut hiking shoes are lighter weight, easy to pack, highly versatile, feel fast and are a great choice for lighter loads and well-maintained trails. Due to the lower cut, they do offer less roll resistance and therefore ankle protection and you might get a little dirt, debris or mud inside your shoe.

Mid Cut – Offering greater ankle support and protection from dirt and debris, mid cut hiking boots provide ankle support and are a great choice for carrying a pack with weight and/or a multi-day trip.

High Cut – The high cut boot’s upper rises above your ankle to provide maximum balance and support. This type of boot is dialed for longer treks, orienteering off-trail and carrying heavy loads (+30lbs).  Boots designed for snow and winter conditions are generally offered in the high cut style.

2. Boot Anatomy: Materials and Construction

Shoes are comprised of three main parts, the Upper, Midsole and Outsole. Below, we detail how our hiking shoes are made and the function of each piece of the shoe.


The Upper - You have two main material choices when selecting a hiking shoe upper: leather or synthetic

Leather - Beyond cosmetic appeal, the type of leather used in hiking and casual footwear manufacturing has a strong effect on waterproof capability, durability and affordability. We use the following leathers in Merrell footwear.

• Full Grain Leather – The outer surface of the leather, usually the strongest, most expensive part of the hide, can be smooth, shiny or textured and responds well to various waterproofing agents. Subject to nicks and abrasion but its general thickness and tight knit fibers give it durability.
• Reverse Full Grain Leather – Same as full grain, but inside out. The strongest, most durable leather due to its inherent thickness and because the rough exterior withstands abrasion.
• Nubuck Leather – Full grain leather that has been buffed to reduce irregularities in the hide. Responds well to embossing, pressing and various waterproofing agents. (Note: Waterproofing will usually result in a darker appearance)
• Split Leather – The split side of the hide once the full grain part of the leather has been removed. Extremely durable because the rough exterior stands up well to abrasion. The most affordable leather available. Can be oiled, waxed and buffed (suede) to improve appearance and water resistance. Slightly looser fibers than full grain provide a softer feel. Also referred to as dura leather.
• Pigskin Leather – This leather is ideally suited for unique color requirements. It is treated with leather protectors during the retan and coloring process, offering superior performance against water and stains.

Synthetic – Manmade materials are also an option to create the upper of a hiking shoe.

• Ventilated – For warmer weather climates and very dry conditions, an upper made with ventilated mesh can be a great way to stay cool by letting air flow around your foot. The mesh is durable enough to keep debris and dirt out. Check out Merrell’s Ventilated Hiking options.
• Waterproof Synthetic Leather: These leathers are vegan-friendly, and often function similarly to leather, adding water resistance and durability. They also offer a mid priced alternative to traditional leather.

Once you have determined the right upper material, you can look at added linings like Waterproofing or Insulation.

Waterproof Linings - Boots billed as “waterproof” feature uppers constructed with a waterproof, breathable membrane. Probably the most recognized brand name of a waterproof breathable membrane is GORE-TEX. One downside of waterproof boots and shoes is a trade off in breathability, meaning there is less ventilation: Your feet may feel warmer on hot days, but they’ll be dry!

Shoes become waterproof in one of two ways:

• Full bootie construction, which is similar to building a waterproof sock with no seams into the shoe.
• Seam-sealed construction, which waterproof-tapes pieces of waterproof membrane together in the shoe to make a fully waterproof product.

Check out Merrell’s Waterproof Hiking Products.

Insulated Linings - When the temperatures drop and the snow is falling, look for a boot that provides insulation in the upper to keep you warm. Insulation fibers and materials capture body heat and reflect it back, creating a thermal microclimate inside the shoe.  Many boots offer temperature ratings to give you an idea of the type of climate they are designed for.

Check out Merrell’s Insulated Hiking Products.

The Midsole

The Upper part of your shoe is very visible. But, the midsole is just as important but, generally not as visible to the average consumer. This is the ‘guts’ of the shoe and the place in the shoe construction where we create comfort and stability. The area below, highlighted in orange, is an example of a midsole. It is below the foot bed where you place your foot and above the sole which touches the ground. This section outlines some of the technology which Merrell uses in its midsoles.


Q-Form Comfort for Women

Men and women are anatomically and biomechanically different. Instead of ignoring these differences, Merrell created a women’s specific midsole to provide a soft landing, realign your posture and provide cushioning for all day comfort. Here is a drawing of how we designed the Q-Form Comfort midsole.


Air Cushion
Found exclusively in Merrell footwear, the air cushioned midsole absorbs shocks and adds stability. The disc of cushioned materials compresses to absorb shock up to four times the body’s weight. The orange disc shown below is the Air Cushion.


Outsoles for hiking are categorized by their level of stiffness. The stiffer the boot, the harder it will be and the more durability it offers as you go off the trail. Refer to our FIST scale recommendations above. Rubber is the predominant material used to make hiking outsoles.

On the outsole, be sure to note the Lug Pattern and the Heel Brake:

Lug Pattern – The orientation of the bumps, or “lugs,” on the bottom of the shoe will determine how your foot moves through the dirt, trail and ground you tread. The deeper the lugs, the greater the level of traction will be. You should also note the amount of space between the lugs, as greater space allows dirt mud to slide through the outsole – but too much space also sacrifices traction, so seek a balance!

Heel Brake – You might notice a “heel brake” on the sole of the shoe – a raised heel zone that helps reduce your chance of sliding on steep descents. Some hiking footwear does not use this, encouraging the use of your foot and toes’ natural strength to prevent sliding or slipping on the trail.


The most noted rubber outsole that you can find on a hiking shoe is made by the Italian company Vibram®. The world leader in high performance rubber soles and compounds for outdoor footwear, Vibram® is used in many of Merrell hiking products. See Merrell Footwear with Vibram® Outsoles. Look for this yellow logo.


The three parts of the shoe – upper, midsole and upper – need to be joined together. There are two predominant forms of shoe construction:
Strobel Construction - Currently the more popular type of construction, Stroebel construction attaches the upper and outsole by either using heat to weld materials together, or with adhesives. This creates a very flexible boot or shoe, and sometimes less bulk.
Norwegian Welting sews the upper directly onto the outsole. This creates a very sturdy, although sometimes very stiff, boot. Merrell’s first hiking boot – the Wilderness – use Norwegian Welt construction.

3. FIT: If the Boot Fits…Your feet will thank you!

There are a number of factors which go in to making a well fitting shoe. We are going to share some of the design factors we consider when trying to make a shoe that will fit you. We have also outlined some things that you can consider when assessing proper fit.

Design Factors

Last – A last is a piece of wood, metal or synthetic material roughly following the shape of the foot and acting as a form on which a shoe or boot is made. It is the foundation or ‘vital center’ of all of Merrell’s footwear. Though years of testing, Merrell has designed lasts that specific not only for men and women, but for different kinds of outdoor activities. We feel that shoes should fit snug in the heel and precise over the instep to keep feet from sliding forward. You should have plenty of toe room and be able to wear mid-weight hiking socks or a combination of a light liner with a mid-weight sock.

Women’s Specific Fit – Merrell footwear is especially designed for men and women, with entirely separate lasts for each. From the beginning, Merrell has used separate lasts for men and women. Our women’s lasts have always taken in to account that:

• Women’s feet are narrower than men’s at the ball of the foot, the Achilles tendon and the heel.
• Women have proportionally longer toes than men.
• Women have a higher instep and arch.
• Women’s calf muscles are longer, carrying farther down in to the boot.


Tips for a Proper Fit

Merrell is known for footwear that fits right out of the box. It is important for your boots and shoes to fit correctly and comfortably at the time of purchase. Look for a snug fit across the arch of your foot, in the heel and room in the toe box. Here are some things to look for when assessing the fit of a new shoe.


Front to Back - The best starting point for size is to reference your normal shoe size. We design our boots to fit like your street shoes. No mystery, confusion or conversion. Put the boots on over the correct sock combination without lacing them. Stand up and push your toes forward so they touch the front of the boot. You should be able to slip one finger into the space behind the heel. If there isn’t enough room, the boot is probably too small and you should try the next half size larger. For boots to be used carrying moderate to heavy load (See our Backpacking section), a full finger space is highly recommended as your feet may swell with the weight.

Side to Side – Tap your heal back in the heal cup of the boot and lace them up. The boot should feel snug across the ball, around the instep and in the heel. The arch should be comfortably supported and the toes should be free to wiggle and curl. It is important to check that the instep is snug, which will help give internal control and prevents toes from sliding forward when you go downhill.

Check the Fit – To check the fit in the heel, walk up an incline. The heel should lift a maximum of ½ inch. In a stride, your foot bends at the ball, and heel tries to pull away from the boot. Because of our precise fit, the upper follows the heel. This prevents the slipping and sliding that eventually causes blisters. To check the fit in the toes, walk down an incline. Your toes should not jam in to the front of the boot, but gently tap the front of the footwear.

A Note on Width – The standard/medium width of Merrell footwear is a Men’s D and a Women’s B. If the foot feels too loose or too tight in this width, you may want to adjust the overall volume of the fit. Merrell’s custom fit system of footbeds allows you to modify the volume and width to fine tune the fit of our footwear. While this works for some people, in some cases a standard/medium width may not fit.  In these situations, a wide (EE for Men and D for Women) is recommended.


When we design the fit of our footwear, we considered sock thickness. In choosing socks for Merrell footwear, the following guide should apply.

Hiking Boots - Heavyweight, think, dense socks with or without a liner sock. Example: Women’s Alpenglow or Men’s Courant

Light Hiking Boots or Multi-Sport Shoes – Light or medium weight dense socks. Example: Women’s Siren Sport or Men’s Chameleon Stretch

We hope this information will help you enjoy your next outside adventure. Please share with us any pics or stories from your trip – Facebook