Brooks Glycerin Flex: a modern shoe that lets the foot move freely

Brooks expands its lineup with a new arrival: the Glycerin Flex. A model that keeps the comfort DNA of the Glycerin family while adding a key dimension—freedom of movement. Simple in concept but ambitious in execution, the result is a real success: a cushioned shoe that feels modern, yet more flexible, smoother, and more natural through the gait cycle. It’s a direct response to runners who like to feel the shoe adapt to their stride. At a time when maximalist shoes dominate, Brooks stands out here by offering a truly distinctive running experience.

| The Glycerin: a historic line at Brooks

Before diving into the Glycerin Flex, a bit of context. Since the early 2000s, the Glycerin has been one of Brooks’ flagship daily trainers—shoes built for everyday running. By 2025, the line reached its 23rd version, proof of a timeless model that continues to attract runners year after year. Hugely popular in the U.S., the Glycerin long embodied a classic vision of comfort: lots of foam, a reassuring structure, and a stable ride. In short, a highly protective shoe designed to absorb impact—sometimes at the expense of flexibility or dynamism.

That approach made the Glycerin successful for years. But running has evolved. The “premium daily trainer” category has changed: runners still want protection, but they now expect more responsiveness—and for some, more fluidity, more natural motion, and less imposed rigidity.

That’s exactly where the Glycerin Flex fits. And no, Brooks isn’t reviving the barefoot trend of the 2000s. Despite its impressive flexibility, the shoe maintains substantial cushioning with 36 mm at the heel and 30 mm at the forefoot, for a 6 mm drop. Proof this is a modern take on comfort, not a return to minimalism. Brooks had explored flexible shoes before (notably with the PureFlow line), but the Glycerin Flex marks a return to this segment with modern, far more advanced technologies.

| DNA Tuned foam: protective cushioning with dynamic response

At the heart of the Glycerin Flex is DNA Tuned, Brooks’ nitrogen-infused foam built with a dual-cell structure. Introduced in 2024 with the Glycerin 22, this technology replaced the brand’s former single-density midsoles. The result is a more efficient foam with better energy return.
✔ Larger cells in the heel: soft, progressive ground contact—ideal for easy paces and long runs.
✔ Smaller cells in the forefoot: a more reactive feel during toe-off and propulsion.

This approach preserves generous cushioning without feeling overly mushy. Brooks also emphasizes a more streamlined manufacturing process, using one continuous foam rather than stacked layers, delivering a more uniform underfoot experience.

© Brooks

© Brooks

© Brooks

© Brooks

| A flexible shoe that lets the foot express itself

What truly sets the Glycerin Flex apart is its intentional flexibility. In hand, the shoe is impressively easy to bend. To achieve this, Brooks integrated:
✔ an asymmetrical flex groove at the midfoot,
✔ modular lateral flexibility in the forefoot.

The goal is to let the foot move naturally—especially during transitions and propulsion. The shoe doesn’t force a motion; it adapts to each runner’s foot while maintaining a stable, protective, and reassuring base.

Brand testers also note that the Glycerin Flex feels closer to the ground than many competing maximalist shoes, while still providing genuine long-run protection. It’s a rare philosophy today, in a market dominated by stiff, maximal platforms.

| A comfortable fit, true to Brooks DNA

The knit upper is soft and highly breathable, designed to follow foot movement without pressure points. Midfoot support is present but discreet—classic Brooks comfort. The heel remains stable, the overall feel reassuring yet never restrictive. A shoe that almost disappears on the run—even as the miles add up.

| Who is it for?

The Glycerin Flex occupies a unique space. It can be considered a daily trainer for everyday and long runs, but it adds a distinctive sense of flexibility and foot engagement. Ideal for:
➜ Neutral runners
➜ Daily easy runs and aerobic endurance
➜ Long runs at controlled pace
➜ Runners who prioritize comfort and smoothness over explosive rebound
➜ Runners who enjoy a supple, flexible shoe

It’s not a speed shoe. Not an ultra-protective maximalist. No carbon plate, no aggressive rocker. It’s a modern, comfortable training shoe designed to run often, run long—and let the foot work naturally.

| The Brooks Glycerin rotation

The Glycerin line has proven itself for over 25 years—and it keeps evolving. Today it offers distinct options for different runner profiles:
➜ Glycerin Max 2: maximum cushioning for the ultimate comfort experience and high mileage
➜ Glycerin Flex: flexible daily trainer for a more natural stride
➜ Glycerin 23: Brooks’ iconic model, a classic daily trainer for everyday runs
➜ Glycerin GTS 23: added structure for runners seeking stability

| What really matters

With the Glycerin Flex, Brooks delivers a genuinely unique shoe in the running market. It refines its craft by offering a compelling alternative to conventional trainers. Flexibility is the shoe’s standout feature, paired with a foam that supports the stride rather than constraining it. This is a shoe for mindful running—where the foot can truly express itself. It will resonate with runners who value a natural stride while still enjoying lasting comfort.

The Brooks Glycerin Flex clearly stands apart from current trends: less rigidity, more feel, more foot engagement—without sacrificing protection. A shoe designed for those who want to run long, freely, and without unnecessary gimmicks. Coherent, intelligent, and unmistakably Brooks.

✔ The Brooks Glycerin Flex will be available on January 30, 2026, at Brooksrunning.com for €180.

Clément LABORIEUX
Journaliste