Mizuno Wave Sky Neo vs Wave Sky 4 Comparison Shoe Review

by Sportitude
12 Feb 2021

Josh reviews the Mizuno Wave Sky Neo running shoes, a new innovation to the Mizuno high mileage family that puts plush cushioning front and centre. Engineering-wise Mizuno have thought of everything when it comes delivering the softest ride yet in their neutral line-up while ensuring all elements of the running shoe work in harmony.

Following in the footsteps of the Mizuno Wave Sky 4 it is free of medial support and is built on a full ground contact outsole for smooth transitions, and yet the outsole has been totally re-engineered. Mizuno have cut back on the flex grooves, teaming the cloud-soft midsole with a slightly more rigid outsole.

The Mizuno Wave Sky Neo has a completely fresh underfoot sensation compared to the Mizuno ‘norm’, being a firmer feel underfoot. The super plush ride is where this shoe stands out from the pack – pairing bouncy Mizuno Enerzy Foam and an ultra-soft Mizuno Enerzy Core to float over the pavement.

The softer cushioning technologies are placed closer to the ground for shock absorption, whereas the denser U4ic foam is used as a top layer for a stable feel on such a plush platform. Up top the one-piece bootie upper creates a natural, sock-like wrap while the knit material offers a blend of structure and surprising breathability to tackle longer runs.

Check out the review with full transcript below.

Hey guys, Josh here from Sportitude Running and it’s shoe review time. Today we're going to be talking about a brand-new shoe that has just landed in Australia and it’s called the Mizuno Wave Sky Neo. It is a play on the Wave Sky franchise but being a Neo model, it is a shoe that's going to be targeting a slightly different runner.

This is the softest neutral running shoe that Mizuno have ever made and underneath the foot there is a really plush cushioning system. In today's review we're going to be talking about all the engineering components of the Wave Sky Neo. We’ll talk about the outsole, the midsole where all the magic is and dial in on what they've done with the upper.

We'll compare it to the Mizuno Wave Sky 4 to show you how it is different and what runner would consider both. We’ll also talk about the foot type that could be looking at this shoe and give you all the information you need at home to maybe make this shoe your next purchase for your high mileage running. Without further ado let's get stuck in.

Runner Profile

Before we get dialling in on how this shoe is put together, let's talk about the foot type that could be considering the Wave Sky Neo. It is a neutral running shoe so there's no medial support underneath the arch.

A neutral foot type in a static position may have a higher arch. As that runner comes through from entry point to midstance then to toe-off, the pressure is generally through the central part of the foot, or the runner may tend to under pronate or supinate as they go through their gait cycle. That means that the pressure is on the outside of the foot as they toe-off on potentially the third and fourth metatarsal. However, I'd be cautious about going for this shoe if you are a true supinator.

Also, if you have a neutral foot type but have flatter arches that’s OK. There are neutral runners out there that do have a flatter arch but as they come through their gait cycle heel to midstance, everything looks pretty stable so there's no tendency to favour that medial side. As they transition through to toe-off, second and third metatarsal is where most of that pressure goes as they get ready to engage and get out of their gait cycle.

That's the foot types that could be considering the Wave Sky Neo.


We’re going to talk about the engineering component of the Wave Sky Neo and compare it to the Wave Sky 4 to give you all the information at home and show you the differences between the two. 

First things first, the outsole is pretty different. The only real similarity between the two is the full ground contact. There's rubber from the heel right through to the forefoot so you get a really nice consistent smooth feel on your entry point at the heel as you come through to midstance and get ready to toe-off.

You're always going to have a piece of rubber in contact with the ground and it’s the same thing with the Wave Sky 4. There are two flex grooves on offer through the forefoot versus four and three quarter flex grooves with regards to the Mizuno Wave Sky 4.

The reason they've offered more flex grooves in the Wave Sky 4 is because it's a slightly denser midsole that needs a little bit of help engaging that forefoot to get out of your gait cycle.

The reason they have only two in the Wave Sky Neo is because the midsole is a lot softer. They took out some flexibility in the outsole through that forefoot to provide a little bit more support underneath your foot.


We’re talking about the midsole now, jumping up to the cushioning system between the two. The Wave Sky Neo is incredibly soft underneath the foot and I mean that.

When you put it on your foot it is very bouncy, soft and cushioned. With all due respect to Mizuno, it doesn't feel like a traditional Mizuno shoe on your foot and I think that's part of the brief.

They wanted to make something that was really different to what they have traditionally made. That's why they've gone out in the limb and made this shoe, it is very plush.

The white foam, being the closest foam to the ground is their Enerzy cushioning system. It’s a very soft foam underneath the foot. The grey foam which you see on the top layer is their U4ic cushioning system. It's a little bit denser and that's the closest part of foam to your foot so it is a more stable on top of that really cushioned platform.

The red dot underneath the heel component is the Enerzy Core cushioning system. It has a similar design to XPOP, which was the yellow component through the shank area of the Wave Sky 4. XPOP was that polyurethane cushioning system that had a little bit more kick and a bit more response.

The Wave Sky Neo is all about softness. There's an element of responsiveness to it, but that Enerzy Core cushioning system provides a really soft ride underneath your foot.

It’s a neutral shoe which we've touched on in the intro. Wave technology bonds together the two different materials being the U4ic and the Enerzy foam but there's no additional arch support on that medial side. It really is dialled in for a neutral runner.

While we're talking about all things midsole we’ll touch on the heel-to-toe gradient. It’s on a 34mm heel and 24mm forefoot, being a 10mm offset same as the Wave Sky 4 . It’s a pretty similar profile with regards to the heel-to-toe offset, it's just the Wave Sky Neo is on a much a softer platform.


As we come into the upper, the Mizuno Wave Sky Neo is a very comfortable shoe with a knitted design. Usually I like to start from the heel and work my way to the front but this time I’m going to start from the forefoot and work my way back to the heel.

The knitted design is a very strong, tightly woven knit. It’s very breathable around the top of the toe box so you get enough ventilation for a knitted shoe. Let's be honest, knitted shoes don't breathe quite as well as open engineered mesh but for a knitted shoe this does breathe quite well.

It’s a tighter weave at the point where the upper meets the midsole, being where most of the pressure on an upper is. That's why they've executed a really strong structured weave around that lateral and medial side. The actual support of the upper isn't compromised with the design.

Coming through to the navicular region, it fits pretty firm for a bootie upper. ‘Bootie upper’ means there's no separate tongue that comes into play. It is a one-piece upper - there's no tongue and gusseted design that structurally holds your arch in.

The bootie design almost feels like you don't need to run with the shoelaces. Please don't take my advice on that, use the shoelaces because you'll get a better lockdown. It sucks your foot in and feels nice and secure as you as you sit inside this shoe.

You have a lacing system which interweaves itself on top of that knitted design. Having the one more eyelet allows you to really dial in that locked system.

It’s near on impossible to do a heel lock lace in this shoe but I don't think you need it because it is a deeper construction. Compared to the Wave Sky 4 you can see that change in depth with regards to the height of the heel counter. The Wave Sky Neo is a higher design and it has a slightly more tilted lean towards the back of that Achilles insertion.

From a heel lock component, you're going to get a pretty good dialled-in fit around there so you don't have to trick around too much. You should be able to get a comfortable fit from using your traditional lacing design which still a lot of runners like to use.

I’m a bit of a fan of pull tabs and there’s a large pull tab at the back to get your foot on and inside the shoe. At the back of the shoe there is an internal heel counter structure, a plastic beam that runs around the shoe which keeps your foot nice and stable on top of this midsole.

If I have to be fair, I believe the heel counter in the Wave Sky Neo to be slightly more structured in design than the Wave Sky 4. The reason is to keep your foot stable and on top of this softer footbed.

We've talked about the cushioning system being considerably softer and squishier underneath the foot. If you compromise the amount of support on top of the shoe, you're going to have your foot sitting all over this really smooth or soft and plush platform.

You still want to make sure your foot is utilising all the engineering aspects of this cushioning by keeping it consistent on that footbed. Therefore, there's a more structured heel counter at the back.

It’s designed purely for those heel strikers. If you're a midfoot runner or a forefoot runner you can run on it, but 90% of sales will be to those true heel strikers looking for really soft cushioning underneath the foot.


Let's talk about the widths on offer. There are only your standard widths available which is your B in the women’s and your D in the men's model and they are true to width. If you’re a bang on women’s B width then you’ll be a B in the women’s model. If you're a D width in men’s you’ll fit nicely inside the men’s model.

If you happen to be earring on the wider side, I wouldn’t recommend this shoe because I don't believe there's enough give up top or depth that's going to come into play to make this shoe comfortable for you. It's a pure B width in women’s and a pure D width in the men’s. 

The Wrap Up

In wrapping up the Wave Sky Neo I would like to tell you that two years ago in early 2019 I was invited by Mizuno to go to Melbourne and talk to a couple of their footwear engineers which flew down from Japan. I saw the first prototype of this shoe and I was extremely excited.

From prototype 1 to where we stand today a lot has changed. It's a very refined version of that first concept. They were really chasing that soft cushion feel underneath the foot and they have been able to execute an end product by dialling into what they know and what they provide being Mizuno, a running shoe brand.

They’re not really trying to be something they're not. They still favour structural integrity which they've done for a number of years, but they wanted to play in that slightly softer cushion market. Prototype 1 was probably a little bit too cushioned and a little bit too advantageous for Mizuno. This end product being this refined Wave Sky Neo is an absolute pure cushioned running shoe, that's for sure.

If you have any questions on this shoe please contact our Sportitude shoe experts. If you have used the Wave Sky family previously and you have some feedback, then let us know how you're going. If the Wave Sky intrigues you and you want to know what it goes up against, certainly ask the question and we'll get back to you as soon as we can.

Subscribe to the Sportitude YouTube channel by hitting the red button if you haven’t already done so and we'll keep you up to date with all things new from the running shoe game.

Until next time stay safe, be kind to each other and we'll see you on the road. Take care and happy running.


 Mizuno Wave Sky Neo

  • Support: Neutral
  • Upper: Knit
  • Midsole: Mizuno Foam Wave, Mizuno Enerzy, Mizuno Enerzy Core
  • Heel Height: 34mm
  • Forefoot Height: 24mm
  • Offset / Drop: 10mm


  • Weight: 345g / 12.2oz
  • Width: D (standard)


  • Weight: 285g / 10.1oz
  • Width: B (standard)

Mizuno Wave Sky 4

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