Adidas Prime X Strung 2 After 100 Miles: A Super-Trainer That Rewards a Very Specific Runner

Introduction

The Adidas Prime X Strung 2 is technically the third version of this high-stack shoe, and the second to use the strung upper. Adidas still positions the series as a super-stack racing shoe, but after 100 miles of testing, it reads more like a super training shoe. The weight has climbed enough that it no longer feels like a race day option, yet the foam and durability make it a genuinely strong long run and daily trainer.

Specs and Weight

Weight is where this shoe tells you what it really is. In men’s size 9 it weighs 10.4 oz, in women’s size 8 it weighs 9.9 oz, and testers have measured 10.7 oz and 11.5 oz in larger sizes. That is clearly outside racing shoe territory, even if the Lightstrike Pro foam still feels responsive enough to confuse people. The whole shoe was redone for this version, with a completely different strung upper and setup.

Fit and Upper

The strung upper has stayed consistent across the series, but the fit has not. The original Prime X Strung ran very low in the toe box with more volume and length, and going a half size down made sense. This version fits very true to size, so the downsizing advice no longer applies.

The midfoot sits at a normal width, the heel fits normal to slightly snug, and the toe box sits low. There is no heel counter, which many will appreciate. Because there are few overlays and the one-piece upper has no thick tongue, security is modest. One tester needed to lace lock the left shoe to resolve heel slip as the upper broke in, and the fit loosened slightly in the midfoot and heel over time. Be careful not to overtighten: the thin upper can put real pressure on the top of the foot. Straight-line running is fine, but turning in the shoe is not this upper’s strength.

Ride and Performance

This is a long run and consistent-pace shoe. If you want to hold a steady pace, easy or uptempo, over flat surfaces and even some hills, the Prime X Strung 2 does it beautifully. The Lightstrike Pro foam, layered in what is described as three layers, delivers a steady, consistent bounce that barely changes from mile to mile.

Where it falls short is pace changes. That weight keeps it from feeling nimble enough for quick surges, and as the shoe broke in, the snappy response of the first runs faded. For fartleks and interval workouts, shoes like the Adios Pro 3, the Adios 8, or the Takumi Sen are better tools. This one rewards cruising.

The forefoot is still a little stiff, with aggressive toe spring and two plates in place of the previous rods. It takes a warm-up to settle into the roll, but once there, it cruises for miles comfortably. Calves do get worked, so give the shoe time to warm up before asking much of it.

Stability and Heel Bias

Stability is the most notable quirk. There is a clear medial wedge in the heel, and the posterior lateral bevel is massive. The result is a noticeable lateral bias in the heel and midfoot that shoves some runners outward, even though the forefoot is very nicely centered with mild sidewalls on each side and essentially no flex.

For runners who need some medial guidance at the heel and midfoot, this can work well. For those who supinate heavily without good control, the lateral heel shape may bother the peroneal muscles. Note also that the shoe does not bend at all, so if you need flexibility, look elsewhere. As the foam compresses, some of that lateral bias softens, but it is worth taking seriously.

Durability After 100 Miles

This is where the shoe earns real credit. A tester known for shredding the posterior lateral section of outsoles had, after 100 miles of long and hard efforts, worn only the very top layer of the Continental rubber. The outsole barely shows it.

The realistic expectation is that the mileage you get will roughly match what the shoe costs. It is expensive, but if this shoe matches your mechanics, the durability makes the math look better than it first appears.

Who Should Buy It

This shoe makes sense if you want a high-stack trainer that holds a consistent pace for long efforts, gives a little extra room in the midfoot and heel, keeps the forefoot centered, and delivers serious mileage. It also suits runners who like a bit of medial guidance in the rearfoot and can live with a lateral heel bias. It is a niche shoe built for a specific purpose, and if any part of that profile sounds wrong for you, other options will serve you better. Racing outside of very long road efforts is not its calling.

Conclusion

Is the Prime X Strung 2 what the newest Prime X promised? Not exactly. Many expected a hybrid of the previous version and the Adios Pro 3, or at least the same lighter weight. Instead, the weight went up and the shoe became more of a daily trainer. But for long runs at steady paces, with exceptional durability behind it, it can still be a very rewarding buy for the right runner.