Key Features
- New engineered flat knit upper
- DNA TUNED midsole
- Asymmetrical midfoot flex grooves
- Podular lateral forefoot flexibility
ON THE RUN
Toni: Brooks has done it again—there’s now a shoe for every runner! Enter the Glycerin Flex, launching 2/1/2026. This shoe is perfect for runners who love a lower stack-height trainer with a natural, grounded feel, but still want a little midsole excitement.
The DNA Tuned midsole delivers two distinct experiences: a softer heel and a firmer forefoot, giving a lively, responsive toe-off. As a midfoot runner who tends to land slightly on the lateral side, I immediately noticed the midsole's tiny slices... subtle, but they make each stride feel smooth, soft, and premium.
I tested these in Michigan on snow-packed roads. No spikes, no problem! I stayed comfortably upright stride after stride.
A standout feature is the deep flex groove channel in the midsole/outsole. In a world of high-stack shoes with stiff midsoles, this flexibility feels amazing. The three cuts in the midsole create gentle cushioning on lateral landings, and as my foot moves into toe-off, the flex guides it perfectly. The result isn’t a dramatic rocking motion, it’s a controlled pop, a responsive push that makes every stride feel energized and fun.
If you want a natural ride with a lively twist, the Glycerin Flex has you covered.
THE FIT
Toni: The Glycerin Flex fits true to size. My foot is a glamorous 10.5 medium, with a little extra volume, and this shoe handles both width and length perfectly.
The toebox is classic running-shoe shaped, neither narrow or wide, so your toes sit comfortably.
The real star, though, is the heel fit. This is the best heel I’ve felt in a Brooks shoe. With the Ghost Max 3, I have to heel-lock every time, but with the Glycerin Flex, my foot is locked in the moment I step in. After two weeks of running, I haven’t needed any extra adjustments, and it’s already become my go-to.
The upper is equally impressive, smooth, breathable, and functional, giving a snug, supportive fit without feeling tight. I like to think the Glycerin Flex’s upper invites your foot to the party but still lets it dance freely across the floor. Stylish, comfy, and responsive, it’s a shoe that looks as good as it feels.
THE FEEL
Toni: The Glycerin Flex midsole is a dream, natural, luxuriously cushioned, and surprisingly stable. A midsole that keeps on giving? Yes, please! With stack heights climbing across brands, I hope everyone takes note and delivers more high-quality, low-stack-height shoes like this.
The real magic? DNA Tuned. Bigger cells in the heel give soft, plush landings, while smaller cells in the midfoot deliver a lively, punchy toe-off. That’s the secret sauce. Brooks could have just dropped a premium midsole on and called it a day, but they didn’t. Every detail was thought through, and the result is a midsole that feels premium without ever going flat. Seriously, this is next-level running comfort.
THE NITTY GRITTY
Toni: Right now, I’m using the Glycerin Flex for daily training and tempo runs (3–7 miles). I haven’t taken it on a longer run yet, but one of the best parts of working in run specialty is really testing shoes, taking them out until they might start to break down. Sure, I might be tempting fate, but I do it to give my customers the best insight.
My favorite shoe of 2025 was the Asics Megablast—fun for long runs and makes me feel fast without much effort. In my opinion, it’s the opposite of the Glycerin Flex. I’m loving the transition between the two: the Flex brings me back to my roots with a lower-stack, more natural feel, yet still premium. On high-mileage weeks, I’ll be mixing both, letting my body guide which shoe gets the work.
THE RUNDOWN
Toni: The Glycerin Flex NEEDS to be on every runner’s radar in 2026! After two weeks, I honestly can’t find a single flaw. It’s stealing me away from my high-stack favorite, the Megablast—and I’m not even mad. I still love you, Megablast, but my heart is fully smitten with the higher-cadence, ridiculously comfortable ride of the Glycerin Flex. Now, Brooks… if only you made this a trail shoe, I’d be completely unstoppable. (Wink, wink.)
Meet the Reviewers
