Just like a sequel to a movie, a sequel to a shoe is often highly anticipated.  Whether the original model was a success or not, a sequel is a way for brands to keep the hype behind the shoe alive by improving on what doesn’t work and keeping the elements that do work.

In the last couple of years, we’ve witnessed the arrival of some game-changing performance sneakers. Better yet, in just a relatively short amount of time, footwear brands have introduced follow-up models—some that feature minor changes, and others that have gone complete overhauls for the sake of performance enhancement. Here’s a look at some of the more notable shoes from recent years, along with the sequels they have set the stage for.

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Adidas Energy Boost 1 vs 2

Last year, adidas revolutionized the running game with the introduction of its high-energy return Boost midsole technology. Since then, the Boost midsole has been integrated into numerous Three Stripes models, though the Energy Boost is still where it all started.

A year after its debut, the Energy Boost returns for a second go-around—this time though, it’s even better yet. While the second iteration of the shoe features an identical Boost midsole as its predecessor, the shoe’s upper has been tweaked to give it a more custom fit. Where the upper on the first Energy Boost model featured a Techfit upper with a thin layer of welded overlays, the latest version features a beefed up TPU cage to provide the stability that the previous version fell short on.



Jordan Super.Fly 1 vs 2

Jordan Brand basically did a complete overhaul of the Super.Fly basketball shoe last year. For starters, the brand added its proprietary Flight Plate technology to the sole for a more responsive ride. While you’ll still find the same Hyperfuse upper in the Super.Fly 2 that was featured in the flagship model, the design of the upper has been drastically changed to give it more versatility.

Where the upper on the Super.Fly 1 was a bit stiff and boxed-in, the Super.Fly 2 features one that is lighter and more flexible. More importantly, JB added a built-in inner sleeve in the shoe to give it that glove-like fit that is so popular in performance footwear these days. The shoe’s outsole has been upgraded by adding an exploding star pattern in the forefoot for improved toe-off, which in turn results in greater explosiveness.


Nike Free Flyknit

Nike Free Flyknit vs Free 3.0 Flyknit

In 2013, Nike took two of its most popular running technologies—a Flyknit upper and a Free outsole—and combined them for the ultimate “natural” running experience. This year, the Swoosh is back at it by releasing the follow-up model to the Free Flyknit.

While the original Free Flyknit was essentially a mash-up of a Flyknit upper and a Free outsole, both technologies have been refined on the latest Free Flyknit shoe to take it to the next level. Instead of flex grooves being exclusively on the bottom of the outsole, on the Free 3.0 Flyknit they wrap around the sidewall and integrate with the upper for a complete natural motion. Better yet, secondary hexagonal and horizontal cuts intersect the flex grooves for even greater flexibility.

The shoe’s upper has also been tweaked in the name of improved performance. Though it still features a knitted yarn construction with integrated Flywire, the upper on the Free 3.0 Flyknit features more perforations on the toe box for enhanced breathability.

Nike Free 3 Flyknit


Adidas Springblade vs Springblade Razor

Just as it did with the Energy Boost 2, adidas rolled out a follow-up model to its Springblade shoe this year. The main difference? Once again, few minor tweaks on the upper to enhance fit and overall feel.

While the individually tuned blades on the sole remain untouched, adidas replaced the Techfit upper seen on the initial model with a more porous mesh upper with Sprintweb technology to improve the shoe’s stability and support, as well as its breathability. The shoe’s heel counter and overlays have also been adjusted to give it a more streamlined look.



Under Armour SpeedForm vs SpeedForm Apollo

The SpeedForm Apollo may seem identical to the original SpeedForm model to the untrained eye, but the shoe does feature some minor changes to elevate its performance. At 6.5 ounces, the Apollo weighs in slightly heavier than its predecessor. Much of the weight gain can be attributed to the addition of a new supportive TPU curve, which helps with stability and improves the shoe’s range of motion. UA also did away with the “guided fit” forefoot design on the original SpeedForm, which featured a rib-like construction, in lieu of a flat, more streamlined one on the Apollo.

As for the shoe’s frame, runners can expect the same responsive cushioning and plush feel the first version is known for.

Under Armour Speedform Apollo