Adidas UltraBoost 5X Review: Is UltraBoost a Running Shoe Again?

Introduction

The Adidas UltraBoost 5X arrives with a clear brief: make the famous franchise a genuine running shoe again. The changes start in the midsole, where an updated Lightstrike Boost compound moves a lot of the foam from the decorative heel bulge of previous generations into the forefoot, exactly where feet hit the ground. Despite adding more forefoot foam, the shoe is noticeably lighter than recent versions, and the signature Primeknit upper stays as comfortable as ever.

The result is a shoe that feels like a real step back toward the early UltraBoosts many runners enjoyed, though it is not without trade-offs.

Specs and Design

The UltraBoost 5X uses a 31 mm stack height at the heel with a 10 mm drop, leaving 21 mm of foam under the forefoot. The midsole is Adidas’ Lightstrike Boost material, first seen in the UltraBoost Light and now carried over to the standard UltraBoost. The outsole is Continental rubber with cutouts that shed weight and offer a view of the updated torsion system, which uses a central oval with spokes radiating outward to keep the shoe from twisting too much at footstrike.

At 9.7 oz (275 g), it is lighter than UltraBoosts of years past, though the plush heel padding and knit upper still place it on the heavier side for the daily trainer category.

Who This Shoe Is For

This is a max cushion daily trainer aimed at easy runs and laid-back long runs. It suits runners who want a comfortable, stylish shoe that can genuinely be run in, rather than the running-inspired casual shoe the UltraBoost had drifted toward in recent years.

Bigger or taller runners may get even more out of the slightly firmer Lightstrike Boost, since their weight interacts with the foam differently than lighter runners.

Main Strengths

The forefoot is the story. Shifting the Boost volume forward means you feel the cushioning under the pads of your feet, where you want it most while running. The Lightstrike Boost absorbs impact well and offers a decent amount of rebound without being overly mushy, a real improvement over the softer Boost of earlier versions.

The Primeknit upper remains arguably the best knit material in running, and the heel padding is plush and luxurious without the excessive puffiness many rivals carry. The 5X version strips away the chunky plastic cage found on the standard UltraBoost 5, keeping only slim overlays and a small plastic eyelet structure sewn into the tongue, which helps with the weight reduction.

Things to Consider Before Buying

The main trade-off is that Lightstrike Boost is firmer than the Boost of memory, but not quite as peppy as you might expect in exchange for that firmness. It sits in a middle ground: less mushy is good, but the shoe never feels dynamic or snappy. There is something a bit underwhelming in the ride, even though easy and recovery paces are genuinely enjoyable.

Price is the other sticking point. At $180, it feels like a lot of money for what you get, even if the UltraBoost has held that same price since roughly 2016 or 2017, making it perhaps the most inflation-resistant shoe in running.

Buying Advice

If the UltraBoost 5X becomes your daily trainer, it pairs naturally into a rotation with the Adizero Adios Pro 3 as the race day shoe, with the Adizero Boston 12 sitting in between as the faster workout option. Runners wanting a fourth shoe for pep on long runs could add the Prime X 2 Strong, which is designed more as a long run and long run workout shoe.

Against the competition, the Saucony Triumph RFG is the closest rival at $160, using a slightly firmer eco-friendly foam that delivers a very similar midsole experience, though the 5X wins clearly on upper comfort and looks. The On Cloudmonster 2, also $180, delivers a similar max-cushion daily trainer sensation with its own aesthetic, so the choice between those two largely comes down to whether you want a knit, sock-like upper or On’s Swiss-engineered look.

If you can, consider joining AdiClub, a free membership that offers early access to shoes before general release.

Conclusion

So, is the UltraBoost a running shoe again? Definitely yes. The UltraBoost 5X is a real improvement and a clear step in the right direction, even if it feels like a transitional shoe between the casual-leaning UltraBoost 19 through 21 era and whatever the franchise ultimately becomes. For easy-paced running in a comfortable, premium-feeling shoe, it earns its place, provided you accept the price and the unremarkable snap in the ride.