Saucony Zealot ISO vs. Saucony Breakthru review

Saucony Zealot ISO provides a smooth ride with a very cushy forefoot. Saucony Breakthru is a lightweight neutral running shoe with a good amount of responsive cushioning.

The Saucony Zealot ISO and the Saucony Breakthru are both neutral cushioning running shoes and actually look very much alike in what they provide.

There is one big difference that can be found in the upper.

The Saucony Zealot ISO has sturdy ISOFIT overlays wrapping the midfoot around a bootlike mesh construction, while the Saucony Breakthru only has a couple of overlays wrapping the midfoot.

The Saucony Breakthru has a sturdy stitched-on overlay on the medial side of the upper that runs to the back of the shoe. Stitched-on overlays can also be found on the lateral side wrapping the heel.

However, the entire toe box is free from overlays, and structure and support are only provided by the mesh in that area.

The Saucony Zealot ISO, on the other hand, has light welded-on overlays running over the toe box to add structure and support. In addition, it has a Support Frame at the back of the shoe to really give you a good lockdown there.

All in all, the Saucony Zealot ISO has a much more supportive upper than the Saucony Breakthru, but as a neutral runner, the amount of support provided by the Saucony Breakthru should be enough to keep your foot on the platform.

Both the Saucony Zealot ISO and the Saucony Breakthru provide heel-to-toe cushioning, but the Saucony Breakthru is meant to be moderately cushioned, while the Saucony Zealot ISO is meant to provide plush cushioning.

The midsole of the Saucony Zealot ISO consists of material that is supposed to provide 20% more cushioning than the material used in the midsole of the Saucony Breakthru.

However, running shoe lab tests reveal that both running shoes are almost equally cushy for men with the Saucony Zealot ISO having just a tad more forefoot cushioning than the Saucony Breakthru.

For women, there are bigger differences to be noted with the Saucony Breakthru having a very cushy heel and the Saucony Zealot ISO a very cushy forefoot.

So heel-strikers may want to consider the Saucony Breakthru more than the Saucony Zealot ISO, and runners who like a cushy forefoot may want to look into the Saucony Zealot ISO more.

Both running shoes target neutral runners, so do not come with stability features other than the crash pad that is located under the heel of the Saucony Zealot ISO, which serves to stabilize the initial part of contact with the ground.

The Saucony Breakthru does not have a crash pad like the Saucony Zealot ISO. Its midsole consists of just one layer of foam. It does come with a separation of its rubber compartments under the heel, though, which also serves to absorb shock a bit when you land.

Both the Saucony Breakthru and the Saucony Zealot ISO provide a good amount of ground contact, which increases the stability of the running shoes as well as their potential of providing you with smooth transitions from heel-strike to toe-off.

But don't expect to get the kind of stability you would get from real stability running shoes.

The rubber outsoles of the Saucony Zealot ISO and the Saucony Breakthru look different, especially in the forefoot; the rubber compartments are laid out in a different way and the Saucony Breakthru has a couple of more flex grooves than the Saucony Zealot ISO.

However, both have a good connection between the rearfoot and the forefoot and a good amount of separation between the rubber lugs, although the Saucony Zealot ISO seems to be more segmented than the Saucony Breakthru.

This does not make the Saucony Zealot ISO more flexible, though, because running shoe lab tests have shown that it is a pretty stiff running shoe for both men and women.

And while the Saucony Breakthru is also pretty stiff for men, it is somewhat more flexible for women.

The women's version of the Saucony Zealot ISO weighs about 7.2 oz (204 grams) and the Saucony Breakthru for women weighs 7.3 oz (207 grams).

The men's versions of the running shoes weigh approximately 8.5 oz (241 grams) and 8.9 oz (252 grams) with the Saucony Zealot ISO being the lightest of the two.

If you are a neutral runner who is looking for a soft ride from a running shoe, you could go with either the Saucony Zealot ISO or the Saucony Breakthru.

However, if you are looking for a securely fitting upper, then the Saucony Zealot ISO would be the one to consider instead of the Saucony Breakthru.

Note: The weight of a running shoe depends on the size of the running shoe, so any weights mentioned in this review may differ from the weight of the running shoe you choose to wear. Running shoes of the same size were compared for this review.

The two links above will take you to where you can read more about the running shoes.

This review falls under: Saucony

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