Adidas Prime X2 Strung First Run Review: A Max-Stack Super Trainer That Rewards Pace

Introduction

The Adidas Prime X2 Strung is a tricky shoe to classify. With a 50mm stack height and two carbon plates, it is legal for elite competition, yet Adidas has designed it as a trainer for recreational runners. At £250 or $300, it sits firmly in premium territory, so the obvious question is whether it earns its price.

Having spent roughly 40km across several runs in it, including intervals, a tempo session and a parkrun, our impression is largely positive: this is a noticeably better shoe than the original Prime X Strung, with stability being the biggest improvement.

Who This Shoe Is For

This is a max-stack super trainer aimed at runners who want race-day-like propulsion for training and faster sessions, with more durability and protection than a dedicated racing shoe. Think of it as a shoe to take pressure off your top-tier racing shoe while still letting you run quick.

It rewards pace. The stiffness of the dual plates is obvious when you start out, and slow, easy running is not where this shoe shines. Once you pick the speed up, it feels lively, rolls you forward and genuinely feels like a race shoe.

Main Strengths

The headline change is stability. The original Prime X Strung had a 50mm stack with a thin midsole and a large cut-out in the lower section, which made it feel wobbly and nervous, especially when turning corners at pace. The new version adds a much wider base and extra foam where the cut-out used to be, and it is a significantly more stable shoe as a result.

Underneath, the previous energy rods have been replaced with dual carbon plates sitting within three layers of Lightstrike Pro foam. Some runners found the original poppier and bouncier; the new version may have lost a little of that, but it gains consistency and efficiency in return. During a 40-minute 10K-pace segment, the shoe smoothly carried the pace without complaint, and a parkrun in it felt fast and genuinely lively.

Other updates matter too: a slightly wider base for stability, an updated Continental rubber outsole for grip and durability, and a redesigned Strung upper with a new sock-like stretchy section across the midfoot. At 298 grams (10.5 oz) in a men’s UK 8, it is roughly 50 grams heavier than the original, yet that weight did not show up on the run. The 6.5mm drop keeps it in familiar racing-shoe territory.

Things to Consider Before Buying

Fit is the main caveat. The Prime X2 Strung is narrow, and even a tester without particularly wide feet noticed the upper pressing out at the sides. Runners with genuinely wide feet are likely to struggle. There is also limited forefoot room, so some runners may want to go up half a size, and Adidas uppers tend to be shallow over the toes, which has caused rubbing issues on other Adidas models in the past, though no rubbing occurred in about 40km of testing so far.

The heel is still a lean, pointed piece of fabric with minimal padding. It is a little softer than the original, which caused serious heel rubbing, and no issues have appeared in testing so far, but longer runs remain an open question. The all-in-one tongue design also produced some lace bite, and getting a secure lockdown takes some fiddling with the laces.

Finally, this is not a versatile easy-day shoe. It is stiff, it is expensive, and it works best when you are running quicker.

Buying Advice

If you have narrow feet, run a mix of tempo work, intervals and longer sessions, and want a stable max-stack option that can genuinely go fast, there is a lot to like here. The wider base makes it a far less risky choice than the original, which was hard to recommend to beginner runners.

Against other big-stack super trainers like the New Balance SC Trainer v2 or the Saucony Endorphin Pro-style alternatives, this feels nicer at quicker paces, though it is not a shoe you want to ease off in. If your running is mostly slow and easy, look elsewhere. If pace features in your week, the Prime X2 Strung is worth a close look, keeping the narrow fit and premium price in mind.

Conclusion

The Adidas Prime X2 Strung is a vast improvement on the original. It may have traded a little bounce for stability, but it feels like a consistent, efficient cruiser that encourages good form and comes alive at faster paces. Fit remains the deciding factor: narrow-footed runners should be very happy, while wider feet should look carefully before committing.