Verdict from 2 experts and 79 user reviews

8 reasons to buy

  • The reflective design of the Altra Impulse Flash is what impressed a majority of users the most. These users referred to the reflective design as “cool” in their reviews.
  • Most testers thought that this shoe and its features were worth the price.
  • One user said that the shoe performed sufficiently on both trails and roads.
  • Some users felt that it offered lightweight support for the feet.
  • Many testers observed the comfort that it provided.
  • The Toe Shape feature of the shoe was well received by several runners.
  • Testers with wider feet were happy about the accommodating fit.
  • Some testers were glad that this shoe had more cushioning than the Altra Impulse.

3 reasons not to buy

  • One runner felt that the design of the shoe looked boxy or bulky.
  • Several users questioned the durability of the shoe because its components apparently felt very light and flimsy.
  • Many users were not happy with the shoe’s ventilation. They mentioned that their feet easily felt the heat after running, even with the tongue and lacing loosened.

Bottom line

Altra’s Impulse Flash is a unique stability shoe that combines comfort, support, and style. This affordable road running shoe was made for the person who is looking for a cool option that has enough arch support, as well as a lightweight frame.

Tip: see the best running shoes.

Good to know

  • On-lookers will be mesmerized by the reflective properties of the upper of the Altra Impulse Flash. Whether it is day or night, the upper of this shoe will look like it is lighting up with every stride. Style-wise, this makes the shoe unique, but the design also serves more practical purposes, especially in environments where the lighting is low.
  • The Flash version of the Altra Impulse also features Altra’s FootPod technology, where both the pattern of the outsole and midsole of the shoe are mapped according to the bones and tendons of the feet. This makes it possible for the shoe to move together with the foot naturally.
  • With its zero drop platform, the Altra Impulse Flash remedies the pain felt in certain areas of the foot or leg when running for a long period of time. It is also responsible for giving runners a more efficient and natural stride.

The Impulse Flash by Altra comes in with standard shoe lengths. Those interested in the shoe can order a pair in their usual sizes. The same goes with the shoe’s width – it comes in standard measurements. Ladies will be able to get the shoes in B – Medium width, while gentlemen have the D – Medium width.

The outsole of the Impulse Flash has two technologies that help with flexibility, support, and protection. It starts with the InnerFlex technology. Normally, a regular shoe’s outsole would only have patterns on the part that can be seen. With the InnerFlex, mapped-out patterns that improve the shoe’s flexibility are found both on the outside and the inside portion of the mid-sole.

The StabiliPod technology is found on the outsole, as well. This design is composed of three pods that were purposefully placed on the heel, and the side-mounds of the platform. These pods are like tripods, preventing the foot from collapsing or pronating excessively.

The material the outsole is made of is a lightweight rubber, which helps protect the bottom of the shoe from wear and tear.

This Altra shoe has a moderately cushioned midsole that’s made up of Altra’s special blend of A-Bound technology and EVA foam. The A-Bound is made with recycled materials. Its main purpose is to give the midsole some durability. It also enhances the energy-return and offers the runner a springier step. On the other hand, the EVA foam is more for the runner’s underfoot comfort.

The footbed has a 5mm contour which helps absorb the shock the bottom of the feet receives when running. This feature also enhances the underfoot feel of the shoe.

The upper of the Impulse Flash is a fully reflective material that is lightweight and friction-free. The reflective properties of this upper aims to make the shoe useful and even eye-catching during night runs or runs in environments where there are only a few light sources.

An overlay runs from the sides of the shoe going to the heel. This minor detail offers lightweight support on the sides of the foot, and it helps keep the heel in place. It’s non-reflective, but it enhances the structure of the shoe with its minimal support.

The asymmetrical lacing system makes it possible for the runner to customize the fit. The fit will be more secure as users tighten the laces, so runners won’t have to worry about the shoe accidentally slipping off.

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.