Verdict from 6 experts and +100 user reviews

10 reasons to buy

  • Generally, runners were very happy with the comfortable ride of the Instinct 4.0.
  • There is a natural space for the placement of the foot.
  • The new version is significantly more breathable than the past model, based on several opinions of reviewers.
  • Some runners loved its long-mileage capacity.
  • More than a handful were very happy with its ability to be a gym option.
  • There were those who said that the shoe was light enough for speed runs and for piling on the miles.
  • The 6th iteration of the Altra Instinct (starts with 1, 1.5, 2, 2.5 etc.) is very smooth and well-cushioned, according to some runners.
  • The price is bang for the buck, as appreciated by a good number of runners.
  • Excellent grip on different surfaces is also mentioned by a moderate number of runners.
  • It looks much better than the past model, as commented by a handful of reviewers.

2 reasons not to buy

  • The forefoot and toe box is a bit too loose, according to some runners.
  • A few said that the upper is a bit sloppy.

Bottom line

The Altra Instinct 4.0 is the Intuition’s (women’s only) equivalent for the men’s version. It offers many of Altra’s renowned technologies like the ZeroDrop and the FootShape technologies. With the 6th instalment of the Instinct, runners can get a shoe that has ample protection for many miles on the road, intense workouts in the gym, and easy recovery sessions. It is a versatile workhorse that can take on different tasks, especially for those who are working around a budget.

Tip: see the best running shoes.

Good to know

  • One of the biggest updates offered by the Instinct 4.0 is the removal of the stiff toe bumper. In its place is a more pliable one that creates more space and lessens the risks of irritations or blisters.
  • Altra also created a significantly more breathable model in this shoe. The added holes all over the shoe makes it definitely more well-ventilated than the previous model.
  • A more streamlined look gives it also a more sophisticated appeal that most runners have greatly appreciated.
  • The outsole has more rubber for more grip and better cushioning.
  • Finally, Altra lessened the foam in the tongue as it is not as bulbous as before, while the heel and ankle collar get more foam for a more plush feel.

Altra basically kept the fit and sizing of the previous model with the latest coming of the Instinct. The trademark FootShape last creates excellent room for the toes to splay. While the forefoot and toe box have ideal space, the heel and midfoot are adequately held in place. The sizing runs true. For those who have slightly wider feet, the generous forefoot space should be more than enough.

Altra’s FootShape outsole creates the premium opportunity for runners to have a more natural and flexible ride. The numerous flex grooves and the detailed outsole provide better shock attenuation and responsiveness. Also, with the thicker outsole, the rubber in the underfoot delivers long-lasting performance for the Instinct 4.0.

An injection molded EVA with Altra properties is called A-Bound midsole by Altra. It provides decent cushioning and responsiveness. The full-length construction enhances the movement through the gait cycle. The same midsole material is also found in the Altra Instinct 4.5.

An engineered mesh upper with more holes delivers a breathable and very supportive ride. The Altra Instinct 4.0 has decent flexibility and hold in the right areas for a secure, but natural movement. The upper shows minimal overlays (the logos only on both sides) to provide security. Only the right mix of flexibility and security hold the foot together for extended periods of time.

Jens Jakob Andersen
Jens Jakob Andersen

Jens Jakob is a fan of short distances with a 5K PR at 15:58 minutes. Based on 35 million race results, he's among the fastest 0.2% runners. Jens Jakob previously owned a running store, when he was also a competitive runner. His work is regularly featured in The New York Times, Washington Post, BBC and the likes as well as peer-reviewed journals. Finally, he has been a guest on +30 podcasts on running.