Adidas Adizero Prime X 2 Strung Review: A Fun, Wild Super Trainer With Trade-Offs

Introduction

The Adidas Adizero Prime X 2 Strung is one of the hardest running shoes to classify right now. It carries a 50mm stack height and two carbon plates, making it legal for elite competition, yet Adidas has designed it as a race-day-style option for recreational runners. It costs £250 or $300, weighs 298g (10.5oz) for men in a size 8, and has a 6.5mm drop.

Compared with the first Prime X Strung, the carbon plates replace the previous energy rods and sit within three layers of Light Strike Pro foam. The Strung upper returns with a new sock-like stretchy section across the midfoot, the base is slightly wider for stability, and there is an updated Continental rubber outsole for grip and durability. After substantial testing, the picture is clear: this is a genuinely fun, fast-feeling trainer that loses some of the first version’s magic while gaining comfort and stability, and its price is the hardest thing to justify.

Who This Shoe Is For

This is best understood as a super trainer rather than a flat-out race shoe. It suits runners who want to soak up a lot of quicker mileage without reaching for their top-tier racing shoe: tempo runs, steady runs, marathon-pace work, and long runs at an up-tempo pace are where it shines. If you liked the original Prime X Strung but wanted something a bit more stable and more comfortable, this version delivers on that promise.

It is less well suited to runners hunting a lightweight 5k race weapon or a track interval shoe. At 298g, it is over 100g heavier than something like the Vaporfly 3 and around 50g heavier than the Adios Pro 3, and that weight becomes noticeable in short, fast reps and on twisty courses.

Fit and Sizing

The general recommendation from testing is to go true to size. Testers in UK sizes 8 and 9 were happy in their usual Adidas size, though some noted that Adidas UK sizing runs slightly small, so half a size up may suit those who want more comfort or extra room in the forefoot. The toe box offers a good amount of space, and the upper naturally opens up at the front while narrowing through the midfoot for a more locked-in racing feel.

The Strung upper is the divisive part. The sock-like, bootie-style construction makes the shoes genuinely difficult to get on; one tester with high insteps and wide feet needed a shoe horn to squeeze in, and another found the narrow opening a real struggle despite being fine once running. Once on, the fit is snug and held the foot securely over the big foam stack for some testers, with no heel rub at all, a clear improvement over the first version.

Others found lockdown less convincing. There was some movement in the heel, and tightening the laces did not fully resolve it. One tester experienced discomfort around the lacing across the top of the foot and had to experiment with lacing to avoid slippage. There is not a huge amount of padding, which keeps weight down, but the trade-off is that you may need to work to find the best lockdown.

Ride and Performance

When you are moving with intent, this shoe is excellent. The ride is incredibly springy, lively, and energetic, a big bouncy bounder of a shoe that gives back plenty in each step and spares your legs. The midsole is not too soft or squishy, balancing genuine comfort with bounce, and the wider base adds a feeling of control that the original lacked.

The speed range matters, though. From easy paces up to around marathon pace, the shoe cruises beautifully, and testers consistently reported running faster than their effort and heart rate suggested. Push faster than that and the size and weight of the shoe become more apparent, particularly in track sessions with 800m or mile reps, where the heaviness counts against it late in a workout.

Stability remains the weak point. Despite the wider base, testers found the Prime X 2 Strung noticeably less stable than the already-wobbly first version, with practically no stability at all and the extra forefoot foam creating lateral movement. One tester nearly rolled an ankle twice, and cornering remains a problem, with feet sliding off the base on turns. On tired legs, this lack of stability is especially pronounced, so you need to stay focused on foot placement.

That said, the three-layer Light Strike Pro stack does protect you from road and foot fatigue better than some more direct carbon shoes, which matters most in the closing miles of a marathon when things are not going to plan.

Durability and Outsole

The updated Continental rubber outsole is a highlight. After more than 50km of mixed road running, testers reported no concerning wear, good grip on roads and long straight stretches, and growing confidence that the shoe can handle high mileage. For a shoe with this much foam, the durability outlook is encouraging.

Buying Advice

Think of this as a luxury shoe rather than a necessary one. If you want an enjoyable, bouncy cruising shoe for lots of quicker training miles, and you are willing to pay for it, you will get a genuinely good shoe. It works across a mix of distances, kept testers comfortable through 12 to 15-mile marathon-pace blocks, and could even serve as a marathon shoe for non-elite runners who are not bothered by the weight, though most testers would not choose to race in it.

The value question is real. Cheaper alternatives such as the Saucony Endorphin Speed 3, Puma Deviate Nitro 2, and Adizero Boston 12 offer lighter, more practical everyday performance, and the Asics Superblast is a comparable premium option that handles easy runs better. If you can find the original Prime X Strung at or below its original price, it remains a strong alternative on many fronts.

Conclusion

The Adidas Adizero Prime X 2 Strung is a hugely enjoyable, energetic, and surprisingly well-protected super trainer that rewards quicker running and punishes laziness. Its bootie upper is hard to get on and harder to lock down, its stability is poor, and its price is hard to defend against cheaper rivals. But when you are rolling along at tempo with good form, very few shoes deliver this much fun per mile.