Article by Sam Winebaum
Mizuno Wave Sky 9 ($180)
Introduction
Sam: The Wave Sky is Mizuno’s max cushion, inherently stable, neutral daily trainer. For its 29th edition, it gets a layer of the latest Enerzy NXT foam, a supercritical nitrogen EVA underfoot with below a relatively thin layer of EVA blend Enerzy foam shaped on its top side as a Mizuno Wave plate but here aa foam Wave. a
The upper is a dense, single layer, woven mesh that is very supportive and quite breathable.
With what now is a “super max” stack height of 44 mm heel / 38 mm forefoot (+2mm at the heel and +4mm at the forefoot compared to the 8), it also becomes a 6mm drop shoe.
Given the super max stack heights and broad platform, weight remains very reasonable at about 10.25 oz / 290g US men’s 9. And on the run, they certainly weren’t lumbering or mushy.
Pros:
Steady paces cruiser with some fun supercritical foam return in the mix: Sam/Sally
Lower EVA foam Wave layer is well integrated: adds a touch of inherent stability, easy any pace transitions and some response: Sam
Very supportive and secure upper: Sam
Solid daily trainer for heavier runners and beginners, excellent recovery run shoe for faster runners, protective choice for piling on distance: Sam/Sally
Cons:
Low and pointy toe box. Some will need the 2E wide version. When the upper “warms up” fit improves, some stretch: Sam/Sally
Shallow toe box means size up if in between sizes: Sam/Sally
Stats
Approx. Weight: men's 10.25 oz / 290g US9 women’s 8.5 oz / 241g US8
Sample Weights:
men’s 10 oz / 283g US 8.5
women’s: 8.5 oz / 241 g US W8
Stack Height: 44 mm heel / 38 mm forefoot, 6mm drop
Platform Width: 95 mm heel / 85 mm midfoot / 110 mm forefoot
First Impressions, Fit and Upper
Sam: The upper is a single layer, unlined engineered woven mesh. It is quite thin and dense with not much stretch. It is a very supportive upper. It is decently breathable but not as breathable as the Jacquard mesh upper of the new Wave Rider 29.
Hold helped by the very stout heel counter and the mesh itself is totally secure and confidence inspiring helping the Wave Sky to also be a light stability option, and one without gimmicks or over wrought aggressive medial geometry. Comfort is OK but the toe box, as unlined, is a bit rough feeling due to the woven nature of the mesh.
First try on, and during the first run, had me say the toe box was too low and a bit pointy with the not particularly soft non stretch mesh not helping. By the second run, the pressure over the toes had mostly subsided and fit clearly improved as the mesh stretched with use. I also noticed that after a mile or two into each run the mesh became more accommodating. It is just true to size but, unusually for me and for longer runs, I might want to try the available 2E wide sizing.
Lace up is super easy, although given the relatively low volume of the upper the laces end up almost too short. That said I doubt anyone will need a runner’s knot here to secure the heel! The moderately padded tongue has a narrow strap gusset most likely more to keep the tongue nicely aligned as the upper mesh has plenty of support and the mid foot volume is relatively low.
Midsole & Platform
Sam: The midsole now features as its top layer supercritical nitrogen EVA Enezy NXT foam whereas in the Sky Wave 8 it was a non supercritical Enerzy EVA. The top foam is quite soft and energetic. Below it we have a layer denser but not overly firm stabilizing EVA. Do not come quite expecting the “pure” supercritical softer yet more energetic ride of competitors such as the Nike Vomero Plus, Bondi 9 or Puma Magnify Nitro 3.
That said, the lower layer with its Wave shape provides some stability and response at the road while the Wave shaping delivers an easy flow forward, and regardless of pace which is not easy to pull off with such a giant stack height shoe. The transitions through the gait are smooth and consistent.
The relatively thin layer of EVA, the lower layer, appears to be a deliberate choice by Mizuno to balance the softer, more energetic top layer with enough stability and geometric shaping from the Wave to allow the Wave Sky roll smoothly. It actually feels ike a wave gently headed for shore!
Above what I feel through my gait. I did not closely look at the Wave geometry until after several runs but I clearly if subtly felt each of the elements below.
The softer Enerzy NXT top foam is deeper at the heel leading to friendly heel landings with enough EVA and the big outsole and heel counter keeping things stable
The deeper Enerzy NXT continues at mid foot after a small rise (for stability) just ahead of the heel. One feels a slight settling in that area enabling transition off the heel
The firmer denser EVA rises at the ball of the foot which provides a stable and more responsive area to initiate toe off.
The lower EVA then thins at the final toe off allowing the shoe to flex and the foot to sink into the NXT foam and push away.
Not to worry there is plenty of forgiving cushion in Wave Sky, well managed and controlled for an efficient ride mile after mile.
Outsole
Lots of deep, well segmented rubber with expected excellent durability. The arrangement gives the Wave Sky some flex (it's not a rigid rocker type shoe), helping stabilize it and reduces weight
Ride, Conclusions and Recommendations
Sam: The ride is consistent and smooth in feel at any pace (hard to do with such a huge 44/38 stack), stable, and with some supercritical foam rebound fun that never goes too far afield. By that I mean that the platform with its lower Wave EVA layer keeps the stride tracking forward without over softness or over stiffness. There is abundant protective cushioning.
Easy paces are not cumbersome and moderate daily training paces see more yet noticeable front rebound. I found it to be a fine recovery run, long slow runs and easy days shoe that is light enough and stable enough with the excellent geometry making it no way a chore to run. It is also an excellent choice if you think you need a bit of stability.
Its weight at about 10.25 oz / 290g US men’s 9 is very reasonable for its huge stack and broad platform.
That said, the Wave Sky is not the speedy daily trainer in the Mizuno line up with the Neo Zen, Neo Vista, and for something a bit more traditional than those the Wave Rider 29 the options. For easier recovery days or long slow distance the Wave Sky is my pick in the Mizuno line up.
I do think given the non stretch supportive woven mesh in the toe box area could be relaxed a bit especially in height at the very front. I would likely either go with a wide version or size up in a next pair.
The Wave Sky is a big seller for Mizuno and this update keeps it very much true to what runners like about it: very well cushioned, stable and reliable for a variety of moderate pace runs. By upgrading the foam underfoot to supercritical Enerzy NXT they give their most massive shoe some fun and spunk.
Sam’s Score: 9.2 / 10
Deductions for the low volume and pointy fit upfront and somewhat rough feel of the woven mesh upper there. Some who usually go regular widths (as I do) may want to try the wide versions or size up and especially if you plan to use them for long runs.
6 Comparisons
The new Wave Rider 29 (RTR Review) is a lower stack, higher drop, lighter shoe and more classic 10mm drop daily trainer. It also gets the new Enerzy NXT foam but for its entire midsole (no EVA layer) with its Wave a plastic plate towards the rear of the shoe and it is noticed for sure as a stabilizing element given the soft foam. I mention the Wave Rider here as both while sharing the new midsole foams have distinctly different ride feels, the Wave Rider quick and snappier and while both are “neutral” shoes both are notably stable.
Hoka Bondi 9 (RTR Review) is slightly heavier, has a roomier, softer (and less supportive) upper than here, and a somewhat softer and bouncier supercritical foam ride. It is less stable than the Wave Sky if a bit more exciting. Yes a Bondi that is actually exciting, a first.
Diadora Atomo Star (RTR Review) is beautifully crafted in Italy ($240) and has an equally supportive (and also somewhat low volume toe box) but has a more refined and comfortable (lined) upper. It ride is softer and more exciting if not quite as stable. Not quite as highly stacked, it is 18g lighter, and this felt in combination with its more energetic single density supercritical foam midsole.
New Balance Fresh Foam More v6 (RTR Video Review) has a non supercritical foam midsole and is somewhat heavier with a 4mmd drop and has a clearly softer and bouncier ride leaning more easy easy days than the more responsive Wave Sky. Its upper is considerably broader and higher volume especially in the toe box. Front volume aside, the Wave Sky is a more versatile shoe
Nike Vomero Plus (RTR Review) has about the same heel height at 45mm but has 3mm less upfront as it is a 10mm drop shoe. With all supercritical ZoomX foam it is a livelier riding shoe and has more aggressive waffle type outsole. As with the Wave Sky, it has a very supportive upper and also up front some low volume over the toes. At the same price it is my pick.
Nike Vomero 18 (RTR Review) with its similar to Wave Sky dual foam construction (supercritical above, EVA below) is a 10mm drop shoe (same stack height as the Plus) at about the same weight as the Wave Sky with a more accommodating upper. Ride feels are similar noting the Vomero 18 is $155 to the $180 here.
Tester Profiles
Sam is the Editor and Founder of Road Trail Run. He is in his 60’s with 2025 Sam’s 54th year of running roads and trails. He has a decades old 2:28 marathon PR. These days he runs halves in the just sub 1:43 range if he gets very, very lucky. Sam trains 30-40 miles per week mostly at moderate paces on the roads and trails of New Hampshire and Utah be it on the run, hiking or on nordic skis. He is 5’9” tall and weighs about 160 lbs, if he is not enjoying too many fine New England IPA’s.
