Merrell All Out Blaze Aero Sport

Since their foundation in 1981, Merrell has been relentlessly focused on producing "the best hiking boots ever made". In fact, even their first pair of shoes was hailed by Backpacker Magazine as "the most comfortable and functional boots in North America". Today, Merrell retains those same values that inspired their iconic blue-laced boot in 1983: Comfort, design, durability, and versatility.

The new Merrell All Out Blaze Aero Sport is no exception. With its lightweight, all-terrain design this breathable trail shoe is surprisingly well-rounded. From bustling restaurants to switchback trails and riverbeds, the Blaze Aero Sport is designed to keep feet dry and comfortable no matter where you go. In fact, because of its unique ability to rapidly shed water, this Merrell shoe is often highly praised by paddleboarders and is often marketed as a dual hiking and water shoe. For Merrell fans looking for a great shoe to wear to work or on wet, unpredictable trails the All Out Blaze Aero Sport could end up being their next go-to barefoot shoe.

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Where to Buy
Where to Buy
Pros & Cons
  • Lightweight
  • Good traction on loose terrain
  • Breathable
  • Water-resistant (dries in 24 hours)
  • Cons
    • Supportive, snug feeling in upper some dislike
    • No specialty arch support
    • Key Features
      Several components of the Merrell All Out Blaze Aero Sport mimic features found in the Merrell All Out Peak including a high-quality Vibram TC5+ outsole. This partnership between brands is a match made in heaven for hikers and off-trail runners who are looking for a "barefoot", or more natural, running experience. In fact, Vibram's design team were the creators of the widely popularized Fivefingers running shoes. However, the Merrell All Out Blaze Aero Sport also has uniquely hollowed lugs for lightness. With a lug depth of 5mm, the Aero Sport line is not overly aggressive or rigid. This feature makes them grippy enough for the trail while remaining comfortable even on indoor surfaces. Lastly, Merrell's proprietary M Select gripping technology features sticky, angled lugs for crossing a wide variety of terrain without debris attaching to the outsole of your shoe or hindering your trek.
      Merrell's All Out Blaze Aero Sport also features a shock-absorbent UniFly midsole topped with an antimicrobial M Select FRESH lining. The M Select lining serves to prevent the growth of bacteria and fungus in your shoes (and on your feet) as your feet sweat or come into contact with liquids. This means if you happen to forget to dry out your shoes, or if you go on an extensive paddleboarding adventure, you won't end up with a musty, moldy-smelling pair of shoes. Plus, this FRESH lining is completely removable and replaceable offering you yet another degree of hygiene and protection against fungal infection. Merrell's unique UniFly midsole is made of cushiony yet durable EVA foam that's about 30 percent more lightweight than the Merrell barefoot line. The midsole runs the length of the shoe for maximum shock absorption. Firmer foam pods in the heel and forefoot also allow for firm takeoffs even on wet or unstable surfaces.
      Suitable for both avoiding underbrush and food service spills, the bellows tongue on this Merrell shoe helps keep out debris. As mentioned above, the All Out Blaze line also features a full coverage mesh upper that allows for surprisingly rapid water drainage. In addition, this line boasts a "glove-like fit" from their Omni-Fit™ lacing System. In online reviews wearers heartily agree that this shoe stays molded to your feet even while underwater and without socks. Plus, the molded TPU heel counter increases the wearer's stability.
      Thanks to its UniFly midsole and 5mm hollowed lugs, the Merrell All Out Blaze Sport is a cushioned, yet highly lightweight shoe weighing in around 22oz. That's nearly half the weight of some other comparable full coverage trail shoes! As far as overall feel goes, many wearers report the All Out Blaze to be one of the lightest shoes on the market.
      Merrell's shoes are known for their breathability. The upper of the All Out Blaze Aero Sport is made of a durable, synthetic, lightweight mesh that allows air to circulate your feet freely. Wearers report being able to walk for long periods of time in urban settings (3 to 8 hours) without experiencing damp socks or sweaty feet. And again, the All Out Blaze Aero Sport line is also designed to rapidly shed water when crossing streams or paddleboarding.
      This Merrell shoe is surprisingly comfortable for a wide range of activities: from urban service work to weekend trailblazing, the All Out Blaze Aero Sport should provide long-lasting comfort when properly fitted with the Omni-Fit Lacing system. This is largely due to this line's wonderfully cushioned and supportive EVA foam midsole replete with foam pods. In addition, the TPU heel counter offers yet another degree of comfort when standing or walking for long periods of time. However, not everyone appreciates the snug, supportive feeling offered by the uppers of the All Out Blaze Aero Sport in day-to-day wear.
      The All Out Blaze Aero Sport line comes in a total of seven colorways. Men's colorways include Dusty Olive, Castle Rock/Green, and Blue Wing. Women's colorways include: Black/Aventurine, Sea Pine, Beige/Khaki, and Dark Slate. These color choices range from casual to vibrant making this shoe a great all-around choice for either daily wear or a stand-out look. With other lines only offering one or two colorways, the All Out Blaze Aero Sport is certainly a comparatively stylish choice. In terms of design, the style is meant to be more functional than aesthetically pleasing or fashionable.
      The Merrell All Out Blaze Aero Sport is highly durable in urban settings. However, exposure to water for frequent or extended periods of time (especially salt water) may cause bonding agents attaching the outsole to deteriorate and/or threads in stitching to break. Wearers report this shoe to have an extremely long lifespan (up to 22 years!) when worn in urban settings!
      The M Select lining provides protection against infection (and foul odors) while traveling through wet terrain and rivers. Made of antimicrobial material, it aids in the prevention of bacterial and fungal growth. In addition, reflective textile accents provide some low-light visibility. A wide protective toe box also allows the foot to splay naturally; preventing friction injuries and turf toe before they have a chance to inhibit your daily runs. Lastly, the distinct angled lugs of the Vibram outsole with M Select grip technology offer singular protection from loose, slippery terrain, reducing your chances of injury from falls or unforgiving terrain.
      The UniFly midsole provides the Aero All Out Blaze Sport with excellent responsiveness and a slight cushioned bounce. Moreover, Merrell's distinctive Omni-Fit technology keeps the shoe firmly wrapped around the foot ensuring that the shoe responds with your movements without friction or discomfort.
      The Merrell All Out Blaze Aero Sport does not seem to offer much in the way of specialty arch support since the line focuses on providing a barefoot, neutral feel. Still, thanks to its cushiony UniFly midsole with supportive foam pods in the forefoot, many wearers consider this a good shoe for standing, walking, and hiking long periods. Plus, with its molded TPU external heel counter, the All Out Blaze locks the heel in place and helps to prevent injury.
      The Merrell All Out Blaze Aero Sport is a shoe that equally bears in mind terrain and trekker. Often labeled as a dual hiking and water shoe, the All Out Blaze Sport is designed to cover ground quickly on loose and/or wet terrain. However, Merrell's noteworthy design takes this line one step above your standard water shoe.
      Merrell's Blaze Sport is somewhat expensive. Priced near the top of the trail running shoe range (depending on color and style options), this shoe might not be a realistic choice for a daily walker. However, if you're looking for a shoe to take paddleboarding, caving, or hiking across varied terrain, the All Out Blaze Aero Sport might be the perfect choice for you.
      The unique angled lug design on the outsole of the Merrel All Out Blaze Aero Sport gives this shoe a grippy, stable feel, even while forging creeks and crossing water. The proprietary M Select tread on this line features small, flexible nodes that keep you keep your standing on slick surfaces, but it should be noted that this is not a specialized non-slip shoe.
      In addition to its synthetic mesh paneling, the lug pattern on the Merrell's TC5+ Vibram outsole (the brand famous for its barefoot feel) adds flexibility to this shoe. However, because of the TPU heel counter, this shoe limits the wearer's range of lateral motion and is not suitable for activities that require a wide range of ankle motion (like CrossFit).
      This shoe is stable enough for continuous long hours of wear. The unique M Select lug pattern offers a more comfortable level of stability on wet surfaces than a standard tennis shoe. The TPU heel counter also offers added stability while pushing off loose or unpredictable surfaces. However, this shoe may not be suitable for those who have over-pronated feet.
      The Merrell All Out Blaze Aero Sport is a zero-drop trail shoe designed to emulate your foot's natural arch while barefoot. In fact, many wear this shoe without socks.
      Key Features
      - Textile and Synthetic
      - Imported
      - Synthetic sole
      - Breathable mesh and durable synthetic uppers
      - Omni-Fit lacing system
      - Mesh lining with odor-preventing M Select FRESH technologies
      - Cushioned and protective UniFly midsole
      - TC5+ Vibram outsole with 5 mm lug depth
      Bottom Line
      The Merrell All Out Aero Sport is a welcome addition to the existing Merrell line. This shoe offers a snug, supportive fit with just a little cushion for both wet and dry terrain. This positions the Merrell All Out Blaze Aero Sport as a well-rounded shoe for the service industry and weekend trailblazing alike. Available in several color styles, the Aero Sport also offers a lightweight and snug fit without sacrificing style. Overall, the Aero Sport is a well-rounded, water-resistant shoe perfect for those who are looking for equal parts protection, support, and breathability.
      Where to Buy
      By Stephanie D'Adamo
      Last updated:
      Where to buy
      Best offer on: Jul. 26. 2021

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