Mizuno has been on a heater over the last year or so. When I look around my bursting-at-the-seams running shoe closet, there are plenty of pairs that I really enjoy but don’t necessarily put on all that often anymore. And then there are at least three pairs of Mizunos that I still wear with relative frequency. That’s saying something for someone who has as many shoes in rotation as I do.
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I’m a big fan of the Neo Vista 3 for up-tempo daily training, and the Hyperwarp Pure – the lightweight one that has helped propel me to some speedy half-marathon PRs – has earned its place in the rotation as well. The Wave Rider 30 has become my travel trainer of choice thanks to its looks and overall comfort. I just got back from a weeklong trip to Baltimore, and those were the shoes I brought along. Even on the trails, the visually unique a has seen plenty of action, including tackling the Oregon Trail Runs Marys Peak 25K.
In other words, Mizuno is doing a lot of things right.
Construction
The latest addition to the lineup takes things in a different direction. The Mizuno Sky Prime is the brand’s take on the big, high-stacked, max-cushion daily trainer. With a substantial amount of foam underfoot, it looks ready to provide a generous dose of comfort for runners who want a little more protection from the pavement.
Looks
Mizuno’s road shoes tend to have their own distinct profiles, but one thing I’ve appreciated about the brand is the relatively consistent color scheme across much of its lineup.
The Mizuno road shoes I’ve been wearing follow a similar formula: a primarily white base accented with various shades of blue and red. The Sky Prime continues that look, giving it a clean appearance that fits right in alongside the rest of the lineup. There is also a more neutral black version for runners who prefer something a little more understated.
If you’re someone who rotates through multiple pairs of Mizunos, there’s something nice about having that visual consistency. Each shoe has its own shape and personality, but they still look like they belong together.
Specs
- Stack: 47mm/41mm
- Drop: 6mm
- Weight: 10.4oz (M9)
Upper
The Sky Prime has a substantial amount of material underfoot, but the upper and overall construction don’t make it feel quite as cumbersome as I initially expected. The engineered mesh has some stretch and adaptability, while the gusseted tongue helps secure the foot in place.
There’s also a fair amount of padding around the ankle and heel, along with a relatively stiff heel counter. I didn’t experience any heel issues, but runners who are particularly sensitive to firm heel counters may want to keep that construction in mind.
The shoe also has a wider platform, which makes sense given just how much height there is between the foot and the ground. I wouldn’t necessarily classify it as a wide-foot shoe, but the broader base provides a reassuring foundation for such a tall shoe.
The engineered mesh upper is relatively stretchy and adaptive, allowing it to conform to the foot without feeling overly restrictive. The gusseted tongue is a useful addition, helping maintain a secure fit without creating unnecessary pressure across the top of the foot.
For a shoe with this much stack, getting a secure fit is especially important. I found it to really hug the foot well and a 5 miler out of the box found an extremely nice and comfortable lock – something that a max shoe should provide.
Midsole
This is where the Sky Prime makes its biggest statement (pun intended). With a 47 mm stack at the heel and 41 mm at the forefoot, there’s a whole lot of shoe between your foot and the road.
Despite that substantial stack, I expected the Sky Prime to feel more like a brick than it actually does. It’s still a relatively hefty shoe, as you’d expect from a max-cushion trainer, but it doesn’t feel quite as cumbersome on the foot as those numbers might suggest. I pushed the pace (up to 6:30 at least) and it felt fine for the type of shoe. I wouldn’t push too much pace in it, but it wasn’t dead weight when I did attempt some quicker efforts amidst more maintained endurance ones.
It’s also not simply a mushy mess of foam. There’s plenty of cushioning and comfort, but the midsole doesn’t immediately give way underfoot. While it definitely falls into the soft category, it was more measured than being a complete sinking marshmallow with every step. I felt the ride was a little more structured than I thought I was going to get on first wear and did not feel that the cushioning sacrificed stability.
Mizuno combines nitrogen-infused PEBA/EVA MIZUNO ENERZY NXT+ in the upper portion of the midsole with a more stable lower midsole. The brand’s Foam Wave construction is intended to help deliver a softer landing, smoother transitions and a stable feel.
The wider ground-contact area also helps provide a more grounded platform. There’s no getting around the fact that your foot sits high off the ground, but the broader base helps keep the shoe from feeling unnecessarily precarious.
The Sky Prime isn’t necessarily the shoe I’d reach for when I’m looking to push the pace, but its weight and overall ride seem more manageable than I initially anticipated.
Outsole
The Sky Prime uses Mizuno’s X10 carbon rubber, a durable compound designed to provide extended outsole life.
The rubber coverage is fairly conventional, with most of it concentrated in the forefoot and additional sections on either side of the heel. There’s some exposed midsole material between those areas, which makes sense on a shoe where managing overall weight is important.
The layout doesn’t reinvent the wheel, but it provides rubber in the areas that see the bulk of the contact with the ground.
Conclusion
Mizuno has continued to build a road lineup that gives runners plenty of reasons to look beyond the usual suspects, and the Sky Prime adds a max-cushion option to a collection I’ve already been enjoying.
On paper, it has the ingredients you’d expect from a high-stack daily trainer: generous cushioning, a broad platform, a substantial midsole and a durable rubber outsole. What stands out so far is that the shoe doesn’t seem to rely entirely on softness to deliver comfort. There’s a more accessible feel to the cushioning, and the overall package doesn’t feel quite as cumbersome as its dimensions might suggest.
Another solid effort from Mizuno.
