• Terrain


    Shoes best for road, track and light gravel. See the best road shoes.


    Shoes best for trail, off road, mountains and other unstable surfaces. See the best trail shoes.

    Good to know

    As long as you stick to the road or path, and if you want just one running shoe, buy a road running shoe.

  • Arch support

    Neutral / cushion / high arch

    Shoes for runners who do not need any additional arch support (Around 50% of runners). Best for people with normal, high or medium high arches. See the best neutral shoes.

    Stability / overpronation / normal arch

    Shoes for runners who need mild to moderate arch support (Around 45% of runners). Best for runners with a low arch. See the best stability shoes.

    Motion control / severe overpronation / flat feet

    Shoes for runners who needs a lot of arch support. Best for runners with flat feet. See the best motion control shoes.

    Good to know

    - Rule of thumb: If in doubt, buy neutral shoes to avoid injuries.
    - More about arch support in this video.
    - Find your arch type by following steps from this video.

  • Use

    Daily running

    Cushioned shoes for your daily easy running. Great comfort. See best shoes for daily running.


    Lightweight shoes good for races, interval training, tempo runs and fartlek. Here are the best competition running shoes.

    Good to know

    If you want just one pair of shoes, buy a shoe for daily running.

  • Price
  • Weight
    Men: 9.8oz
  • Heel to toe drop
    Men: 0mm

    The height difference from the heel to the forefoot, also known as heel drop, toe spring, heel to toe spring or simply drop.

    There are many opinions about what a good heel drop is. We do not recommend any in particular. Lean more in this video.

  • Heel height
    Men: 25mm
  • Forefoot height
    Men: 25mm
  • Width
    Men: Normal, Wide
    Women: Normal
  • Release date
    Jan 2018
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Expert Reviews

Experts are runners, who post reviews at youtube, directly at RunRepeat or at their own websites. Each expert is categorized from level 1 to level 5 based on expertise. See stats on expert reviews and how we calculate scores here.

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87 / 100 based on 4 expert reviews

  • 94 / 100 | Road Trail Run

    While I am certainly not a podiatry specialist, The Instinct clearly is a great shoe for runners with problem toes and wide feet given its supremely accommodating toe box. Its volume should allow easy use of orthotics and after market substantial insoles.

  • 90 / 100 | Road Trail Run

    Perfect shoe for those wanting to brush up on form, yet plenty of shoe for the runner wanting a good daily trainer that seems it will hold up well. Wouldn’t race or touch the track in it, but a good tempo day, Fartlek sesh shoe and just plain solid for cruiser aerobic miles.

  • 89 / 100 | Trail and Ultra Running

    All of our testers had some great runs with these shoes. They felt comfortable whether it was a training run/long run or a short speed workout. Doing striders in these felt great.

  • 70 / 100 | Road Trail Run

    While some road shoes work decently off-road, these are strictly road-only: the combination of a generously sized toe box, loose heel and no tread made them feel terrifyingly unstable on off-camber, steep, and/or sandy, slippery terrain.

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  • The weight of this version of the Instinct has been made lighter. The Altra Instinct 4.5 has a reduced weight of 278g or 9.8oz. It’s 6g lighter than its predecessor, the Instinct 4.0, which weighed 284g.
  • The stack height has also been slightly reduced. Instinct version 4.5 possesses a 24mm stack height which is 1mm lower than its former version. Despite this slight decrease, the midsole still maintains its zero heel-to-toe offset to maintain the runner’s feel of the ground.
  • A few design updates have also been incorporated. The most noticeable is on the upper which now has a more modern look. The midsole has been redesigned as well to look updated and faster.

The Altra Instinct 4.5 is only available in men’s sizes. Male runners who wish to have their own pair can make use of their usual size preference. The width also comes in the standard measurement of D – medium.

The Altra Instinct 4.5 sports a full-length rubber outsole. Because the entire bottom part of the shoe is covered with rubber, it ensures that enough protection from wear and tear is delivered.

The tread pattern is unique because it maps out the bones and tendons underfoot with different colors of rubber, as well as several flex lines and grooves. The Altra logo has been incorporated into the tread, but other than that, the design underneath looks anatomically accurate. This is called the FootPod Outsole. With this design, the runner’s foot is not hindered from moving naturally.

The midsole of this Altra shoe features a zero heel-to-toe drop. The heel and forefoot on the platform have the same distance from the ground. Because of this measurement, runners will get a better ground feel. It also promotes natural alignment of the body and a landing which has a lower impact on the joints.

EVA, which is short for Ethylene-Vinyl Acetate, makes up the midsole of the Altra Instinct 4.5. The material attenuates shock accordingly while delivering the right amount of response and energy return.

A top layer was added on the EVA platform to provide extra protection from hard surfaces. Altra calls this layer A-Bound cushioning. It is made of recycled materials. Not only does it offer better defense underfoot, but it slightly enhances energy return from landing.

On the sides of the midsole, grid-like grooves were added. These grids and lines are called Innerflex. The design slightly lightens the weight of the shoe and enables the platform to have more flexibility. With this in place, the midsole performs better allowing runners to reach faster speeds.

The upper is made of Engineered Mesh. The material is structured without compromising breathability. These characteristics afford the runner lesser hot spots and a better fit, which results in a better feeling of security.

The same as the Paradigm 4.0, the Altra Instinct 4.5 was designed with Altra’s FootShape Toe Box. The toes have enough room to relax and spread out naturally because the design of tip of the upper is similar to how the toes aligned. The big toe remains in a straight position for more power during toe-off, and better balance during landing.

There is a 6mm contoured insole. The extra layer adds a bit more cushioning and protection underfoot. Because it is contoured, it follows the natural curves of the underfoot, delivering a more comfortable feel plus a snugger fit.