Brooks Glycerin Flex: a modern shoe that lets your foot do the work

Brooks is expanding its range with a new addition: the Glycerin Flex. It retains 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 genuine success: a cushioned shoe that feels thoroughly modern, yet more flexible, fluid and natural through the stride. It is a direct answer to runners who like to feel their shoes working with their gait. At a time when maximalist shoes dominate the market, the American brand stands apart with a distinctive running experience.

The Glycerin: a Brooks classic

Before looking at the Glycerin Flex, it is worth revisiting the brand’s history. Since the early 2000s, the Glycerin has been one of Brooks’ flagship models in the daily trainer category. In 2025, the range has already reached its 23rd version, proof that this timeless model continues to win over runners year after year. Particularly popular among American runners, the Glycerin long represented a very traditional idea of comfort: plenty of foam, a reassuring structure and a stable transition. In short, it was a protective shoe above all else, designed to absorb as much of the impact of the stride as possible, sometimes at the expense of flexibility or responsiveness.

That approach made the Glycerin a success for years. But running has changed. The premium daily trainer category has undergone a major transformation: runners still want protection, but they now expect more energy and responsiveness. Some are also looking for a smoother, more natural ride, with less rigidity imposed by the shoe.

That is precisely where the Glycerin Flex comes in. And no, Brooks is not trying to revive the barefoot trend of the 2000s. Despite its impressive flexibility, the shoe retains substantial cushioning, with 36 mm under the heel and 30 mm at the forefoot, for a 6 mm drop. This is clearly a modern approach to comfort, not a return to minimalism. Brooks has experimented with flexible shoes before, notably with its PureFlow range. Now, with the new Glycerin Flex, the brand is returning to this segment with modern, considerably more capable technology.

Brooks unveils the Glycerin Flex, a running shoe built around flexibility and freedom of movement. With premium DNA Tuned foam, flexibility and long-distance comfort, it offers a modern alternative to the classic Glycerin for a natural stride and frequent, high-mileage running.

DNA Tuned foam: protective, responsive cushioning

At the heart of the Glycerin Flex is the new DNA Tuned foam, a nitrogen-infused compound built with a dual-cell structure. The technology first appeared in 2024 with the Glycerin 22. Since then, Brooks has moved away from using a single density throughout the midsole. The result is a higher-performing foam with greater energy return.

✔ Larger cells in the heel: for a soft, gradual landing, ideal for easy paces and long runs.
✔ Smaller cells in the forefoot: for a more responsive transition during toe-off.

This approach preserves generous cushioning without creating an overly soft, mushy feel. Brooks also highlights a more streamlined manufacturing process, with fewer layers and a single foam compound developed upstream in the production process, creating a more consistent underfoot experience.

Specifications – GLYCERIN FLEX

Category: premium daily trainer, flexible shoe
Use: daily runs, long runs
Foam: DNA Tuned (nitrogen-infused foam featuring two cell types)
Surface: road
Level: all runners
Weight: 227 g (women’s) / 249 g (men’s)
Stack height: 36 mm / 30 mm
Drop: 6 mm
Available January 30, 2026
Price: €180

A flexible shoe that lets your foot do the work

What truly sets the Glycerin Flex apart is the specific attention paid to flexibility. In hand, the shoe is remarkably pliable and very easy to bend. To achieve this, Brooks has incorporated:

✔ an asymmetric flex groove through the midfoot,
✔ modular lateral flexibility in the forefoot.

The aim is to let the foot move naturally, particularly during the transition and toe-off phases of the stride. The shoe does not try to dictate a movement. Instead, it adapts to each runner’s foot while retaining a stable, protective and reassuring platform.

The brand’s testers also point out that the Glycerin Flex feels closer to the ground than some competing maximalist shoes, while still providing genuine long-run protection. It is an increasingly rare philosophy at a time when maximalist and rigid shoes dominate the market.

A comfortable upper with classic Brooks DNA

The knit upper is highly breathable and flexible. It is designed to follow the foot’s movements without creating pressure points. The midfoot hold is clearly present, but it comes with the discreet, controlled comfort that is typical of Brooks. The heel remains stable and the overall fit feels reassuring without ever becoming restrictive. It is the kind of shoe that almost disappears on the foot, even as the miles pile up.

What type of runner is it for?

The Glycerin Flex occupies a category of its own. It could be classed as a traditional daily trainer, suitable for everyday runs and long runs. But it adds a distinctive sense of flexibility and foot engagement. It should be a strong fit for:

➜ Neutral runners
Easy runs and aerobic base training
Long runs at a controlled pace
Runners who prioritize comfort and a smooth stride over explosive bounce
Runners who prefer a flexible shoe

This is not a speed shoe. It is not an ultra-protective maximalist model. It does not have a carbon plate or an aggressive rocker. It is a comfortable, modern training shoe designed for running often and running long, while also helping strengthen the foot.

The Brooks Glycerin lineup

The Glycerin range has proved itself for more than a quarter of a century, yet it continues to reinvent itself. Today, it offers different models for different types of runners:

➜ Glycerin Flex: flexible daily trainer, ideal for a more natural stride
➜ Glycerin 23: Brooks’ iconic model, a classic daily trainer designed for every kind of everyday run
➜ Glycerin GTS 23: daily trainer with added structure for runners seeking stability
➜ Glycerin Max 2: even more cushioning for an elevated running experience, ideal for handling high training volumes

The bottom line

With the Glycerin Flex, Brooks has created a shoe that stands apart in the running market. The brand is building on its expertise while offering an appealing alternative to conventional trainers. Flexibility is the Glycerin Flex’s main strength, with foam that works with the stride rather than restricting it. It is a shoe that encourages a more conscious connection with the run, allowing the foot to do its work. It should particularly appeal to runners who want to preserve a natural stride while enjoying genuine long-lasting comfort. A more authentic approach to the running shoe.

The Brooks Glycerin Flex clearly moves against the current direction of running: less rigidity, more feel and more foot engagement, without sacrificing protection. It is designed for runners who want to go long, move freely and do without unnecessary gimmicks. A coherent, smart model that feels unmistakably Brooks at heart.

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