The Brooks Glycerin series has a long-standing reputation as a heavily cushioned mileage-eater, and the Glycerin 23 continues that legacy while introducing a few distinct structural updates. It remains a durable, reliable cruiser, but its new midsole setup caters to a very specific running mechanic.
Fit & Sizing: Room to Breathe
Right out of the box, the sizing is exceptionally reliable. Tested in a standard UK 11, the shoe fits true to size. A welcome refinement to the upper is the slightly wider toe box, which provides plenty of volume for natural toe splay without feeling sloppy or loose across the midfoot.
Midsole & Drop: The DNA Tuned Experience
A significant update this year is the shift to an 8mm heel offset, a welcome reduction from the traditional 10mm drop found in previous Glycerin iterations.
The new DNA Tuned midsole employs a dual-density approach: it is noticeably softer in the heel and firmer in the forefoot. While step-in feel is initially quite firm, the foam softens beautifully once you start running—especially in the rearfoot. However, because of this setup, strict midfoot or forefoot runners may miss out on the plush heel cushioning, making this a shoe where heel strikers get the absolute most out of the technology.
Stability, Weight, & Ride
Tipping the scales at roughly 300g, the Glycerin 23 sits on the heavier side of modern daily trainers. Fortunately, you rarely feel that weight at slower speeds. The shoe features a very noticeable rocker geometry that keeps transitions smooth.
For a high-stack neutral shoe, it offers an incredibly stable and balanced ride. Once you roll through the stride, the firmer forefoot foam engages, delivering a surprisingly responsive toe-off. Even when pushing the pace slightly beyond easy effort, the shoe remains incredibly comfortable and composed.
Durability: Built Like a Tank
If there is one thing Brooks is notorious for, it is robust outsoles. The prominent rubber coverage on the Glycerin 23 is exceptional. After 25km of testing, there are absolutely no signs of wear. This thick outsole rubber, combined with the dense midsole foam, guarantees that this shoe will last for a very long time.
The Verdict
The Brooks Glycerin 23 is a dedicated easy-to-steady day shoe, perfect for recovery runs and long, slow miles. While midfoot strikers might find the cushioning setup unbalanced, heel strikers will find a highly protective, durable, and comfortable workhorse ready to take on the bulk of a training block.
Who This Shoe Is Best For
- Heel Strikers: The soft rearfoot DNA Tuned foam provides ultimate impact protection for heavy heel landings.
- Marathon Trainers: The extreme durability and balanced stability make it perfect for logging massive weekly mileage.
- New Runners: An ideal, protective starting shoe for beginners who value high cushioning in the heel.
- Wide-Toe Seekers: Runners who need a true-to-size fit but appreciate a little extra width up front.
Key Features
- DNA Tuned Midsole: A dual-feel foam that is soft in the heel and firmer in the forefoot.
- 8mm Drop: A slightly lower offset compared to previous 10mm models.
- Rocker Geometry: Promotes a smooth, rolling transition to counteract the 300g weight.
- High Durability Outsole: Thick rubber coverage designed for hundreds of miles of abuse.
- Stable Neutral Platform: Provides a balanced, secure landing area without traditional support posts.
