Most max-cushion daily trainers chase comfort by adding more foam and leaning harder into rocker geometry.
The Brooks Glycerin Flex takes a different route: it’s a high-stack shoe that’s built to let your foot articulate more naturally through the stride, rather than feeling like you’re running on one big platform that forces your foot to move with it (rather than the other way around).
It also feels like one of those “innovation lane” Brooks projects where the idea could’ve stayed experimental… but instead landed as a genuinely polished, rotation-ready trainer.
And after testing it, the concept actually shows up underfoot in a way you can feel bring practical benefits on the run.
Key specifications
- Price: For the best price and colorway options, get them here: $170 at Brooksrunning.com
- Weight: 9.2oz / 261g (US M9, my pair)
- Drop / stack: 6mm drop, 36mm heel / 30mm forefoot
- Upper: Flat-knit upper
- Midsole: DNA Tuned (dual-density, supercritical-style feel)
- Outsole: Thick rubber coverage across pods
- Extra attributes: Strategic cutouts + asymmetrical flex grooves, decoupled heel, deep forefoot flex grooves
Sizing and fit
Fit runs true to size, and they have a medium width - classic Brooks fit.
The flat-knit upper does a lot of work here as it stretches where it should, holds shape where it matters, and manages to suit a surprisingly wide range of foot shapes (from narrow to wider) without feeling loose.
Step-in comfort is excellent too, thanks to a stretchy pull tab and tongue that make entry easy, plus a padded heel area that holds the foot securely without feeling aggressive.
One fit-related note: the tongue is comfortable, but it isn’t integrated/gusseted, so if you love a more “built-in” midfoot wrap this doesn't have that but it still feels great to me, and has a very good heel lockdown too.
Performance review
A max-cushion ride that feels “alive,” not detached
The DNA Tuned midsole (same one as in the Glycerin 23) brings the protection you expect from a 36/30mm stack shoe, but the feel is noticeably more alive than a lot of max-cushion daily trainers.
Instead of that purely soft-and-blanket sensation, there’s a bit more feedback and shape to the ride, enough to make it feel engaged rather than floaty.
Alastair Dixon
The real differentiator is a midsole that flexes + articulates, instead of using a rocker
This is where the Glycerin Flex separates itself and puts it square in the unique running shoe box.
The strategic cutouts and asymmetrical flex grooves change how the shoe behaves through the stride.
Rather than feeling like one solid slab rolling forward, the platform flexes and “opens up” as you move your feet - it works with the biomechanics of your feet, rather than controlling them.
It creates smoother transitions by letting different parts of the shoe do different jobs at different moments.
The outcome is subtle in a good way, because it doesn’t force you into a stride pattern, it just makes the transitions feel more natural and fluid.
“Independent suspension” feel through the stride
Between the decoupled heel and the deep forefoot grooves, the shoe can feel like the rear and front of the platform are working semi-independently; almost like independent shock absorbers.
That’s a big part of why it avoids that clunky, one-piece max-cush sensation.
You get cushioning, but the shoe still feels like it’s adapting to you rather than asking you to adapt to it.
Cushion with control, especially on downhills
One of the most noticeable benefits of this design is that it doesn’t get vague when the ground gets uneven beneath your feet. Some max-cush shoes can feel a little disconnected or billowy, like you’re floating just enough to lose precision.
Here, the combination of cushioning and articulation keeps things more controlled, with protection and ground feel.
Alastair Dixon
Smooth rhythm for easy training days
The ride encourages an easy, steady pace, and I have been able to hit a rhythm much sooner than usual in them.
Because it’s not leaning heavily on a pronounced rocker, it doesn’t feel like it’s trying to roll you forward, it just makes it easy to keep turning over naturally.
It’s a daily trainer vibe through and through, but with a fresher underfoot sensation than most shoes in this category, even though it's not perfect.
Outsole grip and durability feel reassuring
The outsole rubber coverage is substantial across the pods, thick enough to take on plenty of miles, and it feels sticky and grippy.
That adds to the “control” side of the shoe’s personality, especially when you’re not running on perfectly consistent, dry surfaces.
Comfort wins… with one hotspot to watch for
The upper and step-in comfort are a highlight for me, but there’s one potential issue worth flagging that you may notice for yourself, possible rubbing or irritation under the ball of the big toe.
I think this sensation is coming from the fact the big toe pod, (let's call it the DNA Tuned pod, since the branding is on the troublesome one for me), had less cushioning and feels more prominent than the surrounding areas.
It makes me a little hesitant to push beyond the 10km distance. It’s not guaranteed to show up for everyone, but it’s the kind of hotspot that’s worth paying attention to early.
Overall though, I love how natural the Glycerin Flex feels, all while maintaining a protective, cushioned ride.
My verdict
The Brooks Glycerin Flex feels like a deliberate, well-executed attempt to rethink what a max-cushion daily trainer can feel like.
You get the protection and comfort you want for everyday miles, but the shoe avoids the overly-rockered, disconnected sensation that turns some runners off high-stack trainers.
It’s a strong option for runners who want high cushioning without giving up control, especially if you like the idea of smoother, more natural transitions driven by flex and articulation (your natural biomechanics).
And interestingly, it feels broad enough that both “max cushion people” and runners who usually prefer more traditional daily trainers could find a happy place here.
If you do try it, I'd love to hear your thoughts! Drop them in the comments below.
I recommend buying these at Brooksrunning.com for competitive prices on running shoes + often sales up to 35% off • Brooks Run Club loyalty rewards • Free shipping for members • Easy 90-day returns • New Run Club sign-up: 20% off apparel
If you haven't already, signup for my free newsletter, and subscribe to my YouTube Channel for more content like this. -Alastair
