I should first admit that I am a Saucony Kinvara addict, having been through at least ten different pairs over the past few years. Despite venturing out with various other lightweight, neutral road shoes, I’ve always come running back (pun intended) to the Kinvara.
However, during triathlon training on the roads, I started to experience some pain in the ball of my foot. I decided to try a more cushioned shoe, but still wanted the low drop (4mm) and good fit I’ve enjoyed with various iterations of the Kinvara over the years.
Having heard that the Saucony Zealot ISO 3 is a plusher version of my trusty old favorites, I ordered a pair and waited in eager anticipation of its arrival. I have run about 50 miles in this shoe so far, and overall I’m pretty happy, with a couple of reservations.
Read on to see if this shoe might be the right fit for you.
Based on other reviews, I ordered a half size up. However, I could probably have gone up a whole size. The Zealot ISO 3 feels snugger than expected, its beefy padding taking up some of its own interior space. I had to switch out the insoles after my first run, as the ones that come with this shoe are cut oddly high at the arch and irritated my (medium arch) feet.
This was unexpected, as Saucony recommends this shoe for high or normal arches—the same as the Kinvara, with which I’ve never had this problem. In short, I strongly recommend trying on in-person, or shopping at an online retailer with a good returns policy. The fit just feels different from the Kinvara 8 (and Peregrine 7 and 8, for that matter).
I’m a forefoot striker, and my toes appreciate having some space to splay. While this is not an unusually wide shoe, there is a fair amount of room in the toe box. The reflective details on the sides, heel, and tongue are also welcome.
The lacing system is different from the Kinvara and feels like it spreads pressure more evenly. The laces themselves are flat, slightly elastic, a good length, and reliably stay tied.
The heel collar of the Zealot ISO 3 holds my heel nicely but the foam padding is just a little too much for me. Perhaps this is because I’m used to a more minimalist shoe. On long runs in hot weather, it becomes bothersome.
At nearly twice the thickness of the Kinvara heel collar, it feels like overkill, but this comes down to personal preference. Thankfully, the shoe does offer enough ventilation to keep my feet from cooking. The tongue stays where it should.
This shoe is pretty average, looks-wise, with a straightforward style. A variety of bright color options are available.
A constant source of disappointment in the Kinvara is its lack of durability.
I tend to notice significant wear on the soles within the first 150 miles. However, the tougher rubber on the outsole of the Zealot ISO 3 gives me a reason to hope that it will hold up for long.
The thick heel is unnecessary for me, as my heel barely touches the ground when I run. The cushioning under the forefoot is great.
According to Saucony, the sole’s Tri-Flex technology “increases force dispersion over a greater surface area while also delivering optimal flexibility and traction.” While I can’t feel any difference in the force dispersion, I can happily attest to the flexibility and grip. For heel strikers, this might support a smooth transition from heel to toe-off.
For long road runs, the cushioning of this shoe feels good, perhaps in part due to the Everun topsole, an extra layer which lies immediately under the removable insole. However, this shoe just doesn’t have the responsiveness that I’m seeking, especially on my shorter road runs.
I also find it to be a less neutral ride than expected. It is edging toward being a stability shoe. It doesn’t completely throw off my normal gait, but it definitely pushes back a little. It took a while to get used to.
- Lightweight for a well-cushioned shoe (and an ounce lighter than its predecessor)
- More durable sole than the Kinvara
- Good forefoot cushioning
- Less responsive than expected
- Overly thick heel collar
- An uncomfortable insole for those with medium or low arches
- Leaning towards a stability shoe (not a con if that’s what you’re seeking!)
I recommend the Zealot ISO 3 for folks like me who love the Kinvara but are seeking a more cushioned ride.
For long, easy road or treadmill runs, or even for non-technical trails, these might fit the bill. For faster road runs, the Kinvara remains king.
Good to know
- To fulfill Saucony’s promise to deliver a lightweight running shoe, the newer version of the Zealot ISO was designed to be lighter than its predecessor. Formerly, the men’s variant was approximately 9.5 ounces or 269 grams. The weight of this current version was further reduced to 8.5 ounces or 241 grams, making it lighter and nimbler.
- The upper was updated with a covering of engineered mesh. This new material is tougher than the one featured in the previous version, but still possesses elastic characteristics to make the top part of the shoe breathable and stretchy.
- The overlays were lessened, making the upper look sleek and minimal. Previously, there was an external cage that acted as the shoe’s saddle, keeping the midfoot in place. This structure has been removed. To keep the midfoot in place and lightly retain the shape of the shoe, FlexFilm overlays were placed on key areas of the upper.
- The proprietary PWRGRID+ on the previous iteration has been removed. The cushioning of the shoe is still plush, but it’s not as plush as the Zealot ISO 2. This redesign, however, has slightly improved the support and responsiveness of this neutral runner.
- On the upper part of the shoe, a molded heel collar was added to help lock the heel down, preventing it from moving while the runner is in motion.
The Saucony Zealot ISO 3 comes in standard running shoe measurements. Runners can purchase a pair using their usual shoe size preferences. It comes in the standard width measurements of B – Medium for females and D – Medium for males.
The shoe is equipped with the ISOFit system. This design innovation allows the runners a custom and secure fit with a cleatie upper construction that’s combined with shoelaces that are looped through synthetic straps.
The outsole of the Saucony Zealot ISO 3 is made up of two types of rubber – the XT-900 and IBR+. These rubbers are appropriately marked upon closer inspection of the bottom of the shoe. The combination of both materials enhances flexibility and durability. These outsole materials are also present in the Saucony Omni 16 and other popular shoes from Saucony.
To be more specific, the XT-900 is the tougher rubber of the two. It is located on the tip of the forefoot and the curve of the heel. These areas are more vulnerable to wear and tear, thus this premium carbon rubber with exceptional traction and durability was added.
The IBR+, on the other hand, has more to do with flexibility. It is approximately 33% lighter and more cushioned compared to the standard blown rubber. This material is placed on the majority of the forefoot, mostly under the medial plantar area of the sole.
Lastly, the outsole was designed with the Tri-Flex tread. The forefoot, mostly, bears a chevron pattern, with indentions through each arrow and between each line. The rest of the tread, especially under the heel area, has trapezoid-like sections with similar indentations.
The entire Tri-Flex tread works with the EverRun Topsole for better dispersion of force upon impact. It also allows the shoe to move together with the runner with lesser resistance while also providing the necessary traction on common surfaces.
The main technology found in the midsole area of the shoe is called Everun. This is mainly responsible for the shoe’s responsiveness. Everun is an extra layer placed nearer to the foot, providing a livelier run while dispersing the impact upon landing. Saucony describes this rubber compound as a mechanism for continuous cushioning. It works by ensuring smoother heel landings and reduced pressure on the forefoot when gearing up for the toe-off.
Saucony saw fit to add a highly elastic sock liner to line the footbed. This affords more cushioning underfoot, accompanying the underfoot comfort the midsole foam already delivers. Runners also have the option to remove this insole to replace it with Ortholites or other custom inserts.
The upper sports different shoe features that permit a custom fit. Starting with the Isofit, this system is composed of two key properties of the shoe – the sock-like construction combined with the unique lacing system.
The sock-like construction made of stretchable mesh that hugs the foot in all the right places. Because it has elastic characteristics, it molds to the shape and size of the foot with ease. The level of comfort this material provides is high, with its soft feel and non-restrictive wrapping.
In addition to the mentioned benefits, runners are given the chance to feel enough ventilation from this material. Because it is made up of mesh, air can easily pass through the network of wires, allowing the heat to escape and the foot to breathe.
The second component of the Isofit system is the lacing which is connected to bands that extend from the eyestay of the shoe. Tightening the laces will also tighten the bands. This produces a more secure fit on the middle part of the dorsal area of the foot.
Flex Film Overlays were added to lightly support the midfoot. These overlays are not just for aesthetic purposes. They slightly enhance the security and snugness without compromising flexibility. The films are also reflective, allowing better visualization when running in low lighted conditions.
The collar lining of the shoe helps with absorbing moisture. Saucony lined it with Rundry, a lining material that has moisture wicking properties. Aside from that, runners also benefit from the plush comfort this material delivers.