Altra One 2.5
The Altra One 2.5 is designed to be a solid performance shoe for runners in need of a low-profile, lightweight training shoe. The One 2.5 checks all the right boxes for runners who demand speed and flexibility in their training shoe. The design is simple, yet refined with the potential to work as a solid cross training option when taking a break from running. The shoe stacks up nicely to some of the other models being produced by Altra. Durability could come into question sooner than desired in some areas of the shoe, but beyond that, this shoe has a lot to offer. Some may be in search of a shoe with more traction and stability but those who are used to the minimal design will really enjoy running in the Altra One 2.5.

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Where to Buy
Where to Buy
Pros & Cons
  • Super Lightweight Design
  • Roomy Toebox
  • Zero Drop
  • Quick-Dry Air Mesh Upper
    • May not be enough structure for some runners
    • Traction could be better
    • Potential durability concerns
      Key Features
      The outsole of the Altra One 2.5 is designed for maximum impact absorption while allowing the foot to feel connected to the running surface. Altra relies on their FootPod™ Technology to make this happen. The shape of the outsole pattern aligns with the anatomical composition of the foot. This means the bones and tendons of your foot will be able to flex naturally without being held back by access bulk that restricts the foot’s natural motion. In addition, the A-Bound™ technology does a wonderful job of maximizing efficiency and reducing the impact of the ground. Each step is properly absorbed and propelled to get the most out of your energy.
      The midsole is a region of the shoe where Altra has really pulled out all of the stops with the One 2.5. Cushioning is vital to the success of a good training shoe, and the One 2.5 does not disappoint. Once again Altra uses their dual-layer EVA cushioning to support the midfoot. There is also more A-Bound™ technology to maximize efficiency. The InnerFlex™ Technology offers a series of flex grooves along the midsole that gives enhanced flexibility. The grooves are arranged in a grid-like pattern to ensure that the foot can flex where it needs to in order to achieve maximum comfort, increased speed, and improved performance.
      The upper material of a lightweight training shoe needs to be able to withstand the heat and speed of a high-mile trainer. This means that the material must be able to flex and breathe. In this case, Altra employs its quick-dry air mesh material to keep the foot cool and comfortable. There is minimal padding around the tongue and collar of the shoe but the trade off in weight is well worth it. Moisture and sweat are able to be absorbed and evaporated quickly. The lightweight material allows just the right amount of airflow into and out of the shoe. The flat laces found on the shoe offer a snug fit with a design that minimizes untying or fraying.
      The weight is a key selling point for the Altra One 2.5. It is positioned as a lightweight trainer and it does not disappoint, weighing in at just 6.3 oz. This puts it on par with some of the best lightweight shoes on the market today and runners will appreciate this on their longer runs. By shaving off some of the access cushioning, Altra was able to make this shoe remarkably light and airy. An added advantage of this lightweight design is the packability of these shoes. The comfort and flexibility of the shoe make it a great travel option when trying to keep the weight of your pack low.
      To accompany their lightweight design, the Altra One 2.5 is also extremely breathable. This makes sense for a shoe that has eliminated any unnecessary cushioning. The quick-dry air mesh material allows air to escape easily to ensure the foot stays cool and comfortable. While this may pose a problem for those running in colder climates, it will be well appreciated on those warmer runs. The breathability also means that the shoe will be susceptible to wetness due to rain or dew-kissed grass. That breathability will certainly preclude it from being found on any list of the top waterproof shoes.
      Comfort is key for a shoe that is designed to be lightweight and breathable. This shoe is so airy that you almost forget it’s a piece of performance footwear. The comfort is enhanced due to the design of the toe box. With ample room to splay and stretch the toes, most runners will love this comfortable ride. The flexibility of the shoe is also very remarkable. Comfort is not an issue when you’re able to easily flex and stretch the foot in every stride. The high level of comfort also makes these shoes great for casual settings or cross-training scenarios.
      Style can be a hard topic to quantify. The Altra One 2.5 is a reasonably handsome shoe. It comes is a host of different colors that should appease even the most finicky runner. The variety of colors will allow for options that blend in as well as stand out. The One 2.5 may not be considered one of the most colorful shoes around, but it does have flair. The low-profile look and subtle branding help round out a very good looking shoe that will appeal to many different styles. The Altra One 2.5 will even blend in nicely in some social situations. Runners may not see a need to run home and change between workouts and social events.
      Durability can be a major concern with shoes that fall on the more minimal end of the spectrum. On one hand, it’s great to trim down the weight of the shoe by eliminating excess rubber and cushioning. On the other hand, these sacrifices can hinder the longevity of the shoe. The outsole and midsole cushioning on this shoe could be prone to some durability issues. The thinness and flexibility of the upper material are wonderful but there could be spots along the outer edge of the foot where holes could prematurely appear.
      The minimal design of the Altra One 2.5 does impact some of its protection. The foot will feel good thanks to the ultralight InnerFlex™ midsole. There will be protection against small rocks and simple road debris. The FootShape™ toe box also does a great job of protecting the foot from bruised toenails, giving them ample room to splay comfortably. The A-Bound™ technology found in the midfoot also helps to absorb excessive impact to protect the foot stride after stride over long distances.
      A lightweight shoe like this offers maximum responsiveness. Runners will feel a direct connection to the running surface when wearing the Altra One 2.5. The roomy toe box allows the foot and toes to land naturally and splay out. The weight-balanced Zero Drop™ platform keeps the shoe low profile and doesn’t feel too bulky or rigid for a responsive ride. The minimal upper design gives the ankle a chance to flex and respond to the demands of the terrain being covered. Runners should have no issues with the amount of responsiveness in this shoe when compared to many of the bulkier, less-responsive options found on the market.
      Support may be an area where some runners feel the Altra One 2.5 falls short. The lightweight cushioning and minimal design mean that there isn’t excessive support for those who may need extra. Fortunately, Altra’s FootShape™ system helps to keep the toes relaxed in a way that balances weight and supports the arch of the foot. By keeping the big toe straight, the foot is able to retain its stability and offer more comfort and speed. Heel strikers and midfoot strikers alike will appreciate the amount of support found in the Altra One 2.5 from heel-to-toe. Those looking for additional arch support may want to try some separate tools to beef up the support.
      These shoes will be most at home on the road or the track. Their lightweight cushioning performs best on even terrain that is devoid of excessive pitfalls. The Altra One 2.5 will be able to handle many of the typical running surfacesthat a runner comes in contact with, but by no means is it a trail running shoe. Runners looking for a more supportive shoe that can handle rugged terrain should look elsewhere at some of the top trail shoes.
      Whenever a shoe packs a lot of technology into its design, you can expect to pay top dollar. Altra prides itself on offering the latest features in all of its shoes. The One 2.5 positions itself on the higher end of the price spectrum. Yes, deals can be found on these shoes if you’re looking hard enough. You likely won’t see the Altra One 2.5 on the list of top discount shoes options anytime soon. For those runners who appreciate the technology and quality found in the Altra brand, they’ll have no buyer’s remorse after purchasing the One 2.5.
      The Altra One 2.5 relies on its InnerFlex™ Technology groove system to give minimal traction. This will offer some help if running over truly slippery surfaces like ice or wet grass. However, there are no protruding lugs or complicated traction systems to be found on this shoe. The Altra One 2.5 is designed to be fast, light, and flexible, this comes with a slight tradeoff in the traction department. Without the added benefit of extra traction, you'd be best served to keep these shoes on less rugged terrain. Runners will notice a difference in texture and traction between the different components of the outsole. An additional form of traction comes along with the FootPod™ Technology found on the outsole of the shoe. This technology adheres to the anatomical components of the foot and helps provide additional traction in the natural form of the foot.
      These shoes are tremendously flexible. Most of this flexibility comes from the InnerFlex™ Technology grooves that are found along the bottom of the midsole. These grooves allow the foot to move naturally and accommodate the rigors of impact. In addition, the flexible air mesh upper material does a great job of moving with the foot over the course of a run. These features allow the Altra One 2.5 to be one of the more flexible running shoe options available on the market today.
      The stability of these shoes comes mainly from the FootShape™ toe box. The Altra One 2.5 allows the foot to land and splay naturally in a manner that ensures ultimate stability. In addition, the FootPod™ Technology found on the outsole of the shoe mimics the anatomical mechanics of the foot. This defers impact to the appropriate portion of the foot to minimize imbalance and encourage enhanced stability. While it may not end up on a list of the top stability shoes, the Altra One 2.5 will meet the needs of most runners.
      The drop here is extremely minimal. Altra promotes their fully-cushioned Zero Drop™ Platform that gives the shoe their minimal feel. Runners who are not used to this may find some discomfort when first wearing the shoes. It’s recommended that you ease your way into a zero-drop shoe in order to properly get used to it. For those runners who are looking for a minimal ride without excessive bulk, the zero-drop will feel wonderful.
      Key Features

      • Quick-dry air mesh upper

      • Zero Drop™ Platform

      • Ultra-breathable mesh upper

      • FootPod™ Technology

      • FootShape™ Toe Box

      • Variety of color options

      Bottom Line
      Runners who are looking for a lightweight, versatile training shoe will have a hard time finding a better option than the Altra One 2.5. It packs a lot of technology into a lightweight, stylish package. It may not have the rugged outsole to perform on tough terrain, but this shoe will really deliver on flat, fast roads and tracks. High-mileage runners will have to keep an eye out for premature wear and tear, but beyond that, there aren’t many flaws to be found with this shoe.
      Where to Buy
      By Chris Jennings
      Last updated:
      Where to buy
      Best offer on: Aug. 04. 2021

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