The Brooks Glycerin 21 sees Brooks update one of our favourite cushioned shoes, adding in more of that soft DNA Loft v3 foam, all while making changes in the upper and outsole departments.

Testers Mike and Kieran have had the new Glycerin in to test to find out what’s new and different from the Glycerin 20, and see whether the changes Brooks has made make it a better, or perhaps even a different Glycerin to lace up.

00:00 – Intro
00:10 – Price and what’s different from the Glycerin 20?
01:37 – How does it fit?
04:26 – The Run Test
11:51 – Verdict & Alternatives

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Hey this is Mike from the r testers and This is our multitester review of the Brooks Glycerin 21 so here's what you need to know about The Brooks Glycerin 21 and what's Different and new from the glycerin 20 The glycerin 21 is a cushioned daily Trainer shoe that offers a softer level Of cushioning compared to Brooks's ghost Range the glycerin 21 is priced at £65 In the UK or $160 in the US making it More expensive than the Gin 20 when it Launched at £50 or $150 it comes in medium and wide fits And is available in a GTS support model Which includes Brooks's guide rail Support system there's also a stealth Fit version which offers a more Streamlined knit upper to sit closer to Your feet big difference to highlight Here is the change in weight a UK size8 Weighed in 280 grams compared to 301 Grams in the same size glycerin 20 it Still has a 10 mm drop with stack Heights are now 28 mm at the hill and 18 Mm at the 4T it now has an extra 2 mm of Brooks's nitrogen infused DNA Loft V3 Cushioning Tech and is placed across a Wider platform than the glycerin 20 has Changed things in the upper Department With a new engineered knit upper Designed to offer roomy and supportive Surroundings there's a new out soole

Here too with a road Tac one in place That uses a of rubber and recycled Silica along with new outsole patterns To offer plenty of grip and Durability first up fit then and I ran In my regular running shoe size Brook Shoe size which is a UK 8 and a half Initially I found the fit pretty snug And in our first run video I said that It was sort of nicely cocooned as you Might expect from big plus shoe I think That's certainly still true of the heel Colors that big padding and those of Plush tongues and that midfoot hold but As I've used this shoe more I've noticed A growing space in the toe box maybe It's just having used it I've gotten a Bit more used to how it feels on the Foot but I think that's down to the Stretchy uppers that you've got here the Toe boox now feels very very roomy and Spacious compared to some other shoes May be bordering on the baggie now That's no bad thing if you want to use These for runs with really long time on Feet even sort of pushing into Ultra Where you want that space time you know Room for your feet to sort of swell and Flex and all of that kind of stuff and Everything else stayed roughly where it Should with good heel hold decent pinch Free midfoot lock down and no troubling Hot spots in any of my runs so overall I'd recommend still going true to size

Unless you like it really snug then There might be an argument to try half a Size down just to dial in that toe boox Somewhat but yeah I I found it fine true To size so fit for me has been overall Very good in the Brooks Glycerin 21 I've Had mine in a UK size eight that has Been the medium width fit as well too so That's the same size and width that I Had the glycerin 20 in a shoe that I you Know I didn't really have any issues in Terms of that overall feeling of running In it no kind of problems in terms of Comfort side of things you definitely a Roomy space to shoot I think it's more Of the same here got pretty narrow kind Of skinny feet and you know in that Medium kind of width fit it's definitely On the room and spacious side I think Maybe you're getting a touch more volume In general in this shoe I think it feels Like there's a bit more material maybe Hugs a little bit closer to your foot as Well maybe Tad more supportive in areas Of this shoe but generally I think the Experience has felt very similar for me It definitely feels like there's extra Things in terms of boosting things on The Comfort side of things so I think You're getting a bit more padding in the Heel so if that's something that you Craze for from the 20 then I feel you'll Getting a little bit more here a Slightly different design in terms of

That padding um kind of layout and Design the tongue is very similar to the One on the glycerin 20 but you are Getting some different laces these kind Of spongy laces that kind of remind me Of the ones we had on kind of previous Versions of things like the socky ride Where again it's all about taking that Pressure off the top of your foot if That's something that you felt didn't Quite work for you on the 20 buff to be Honest I had no issues on that front Then you are maybe getting a little bit More on the Comfort side in that part And that kind of Department of the shoe But ultimately I think both of my Testing I would go true to size I think If you went for a medium width fit uh You know on the glycerin 20 and you Looking to upgrade to the 21 I think go Go the same size same width I think You'd be absolutely Fine okay so into that now I'll start by Saying that I really enjoyed running in The Brooks list in 20 I think it was a Standout cushion shoe for Brooks I think It's my favorite Brook shoe that I've Run in and I think you know I think it Still stands out even though it's been Kind of superseded by the Brooks 21 now Big part of that was that kind of Nitrogen injected DNA LOF V3 midone that Kind of debuted in that Brooks Aurora Concept shoe and kind of made its way

Into the Gin range and I think worked Really well and made it a comfortable Shoe kind of softer feeling shoe cushion Shoe compared to the kind of Brooks Ghost but also I think protected as well Too and I think had a touch of Versatility about it as well which kind Of maybe surprise me a little bit in Terms of my experience and the Gin 21 There is more of that Midol Fame what Does that mean ultim means you're Getting something that feels you know a Lot more plush than the glycerin 20 I Think it still ultimately it's designed There to protect make things comfortable But also enjoyable and there kind of Shorter longer runs as well too and it's About kind of soaking up a lot of Mileage in the shoe like the previous Glycerin in terms of how I use the shoe Marathon training at the moment it's Doing a lot a lot of big longer runs Kind of marathon pace or close to doing Some kind of 10K Pace uh kind of Sessions as well too kind of track Session so this was really a shoe that I Use kind of my easy runs recovery runs Kind of bace runs where I just need to Clock up that kind of running time I did Try and run a little bit more Up Tempo In it because I said I think the Glycerin 20 had some versatility about It that was kind of 8 minute mile kind Of 820 minute mile pace so not my

Quickest but ultimately just to see if It still had that kind of you know you Know versatility about it now what I Would say about thein 21 good thing is It's gone down and weight I never really Felt that the weight was an issue for me On the glin 20 just because I think it's Spread across I say a kind of quite wide Kind of broad platform there is a kind Of broader platform I would say maybe on The 21 but I think you know it's good that It has become light cuz it's definitely Been a trend for shoes in general new Generation shoes to go a little bit Heavier in terms of that extra Midol Foam it definitely feels plusher Definitely feels softer I do feel like You sink into it a lot more than you do On the glycerin 20 what I would say is I Feel like maybe that extra foam has seen The glycerin 20 one for me kind of Veer A little bit into that kind of Max Cushion Territory we've seen Brooks kind of Launch the ghost Max which is kind of Their Max cushion Sho but I feel like That extra Fame what it's done has it's Created something that feels a little Bit more max cushion for me on the GL 21 Compared to the glin 20 and I think Ultimate that has done is taken away a Little bit the Versatility in the 21 it's a bit like

What I saw with the aex GEL Nimbus and The new GEL Nimbus the kind of 25 and 26 Where I think you know you got something That felt plush and very comfortable and Very protected But ultimately it wasn't Something that I personally would want To run more Up Tempo runs in and I feel Like you've lost a little bit of that in The 21 with the 20 it's definitely Plusher definitely feels you know There's that bounce there still but you Know spread across that kind of kind of Wide kind of broad platform so it's you Know very stable as well too you still Get a protection I just think you know When I wanted to run a little bit Quicker in it I felt like it just didn't Work for me and almost having that extra Foam counted against it in terms of that Versatility but in terms when I wanted To run easy when I wanted to run long No emphasis on Pace the shoe felt very Very good to running as I said recovery Runs easy runs long runs this is where The shoe really worked well for me Outsole wise now there's a lot of rubber On the outsole on the G 21 and there was A lot on the 20 so what it tells me is This is a shoe that is built to kind of You know last long and you know for me I Think I'd have no quams kind of logging A lot of mileage in this shoe there's a Lot of rubber the outso pattern has Changed from the 20 it's almost got

Patterns in different sections of fit I Haven't found that that's kind of Changed or drastically changed the Experience of me running in this shoe Maybe just adds that kind of more stable Feel that you're getting here to kind of Counter that extra level of foam that Bounce that you still get in this shoe But ultimately I don't think it's Massively change experience so I've had A good running experience in the shoe as I said I do think maybe by adding that Foam and giving you a softer feel and Still a protective cushion feel you Maybe lose a little bit of Versatility In a shoe But ultimately if you are Using for those long easy recovery runs And I think the bricks gin 21 that is Where it really ultimately excels and I Feel like you know it's worked well For Those runs for Me overall so for my run Test I've now covered around 50 km in The glycerin 21 I've done a mix of paces And terrain some steady 5 to 7 MERS just Slower than marathon pace a short Interval session pushing half marathon Paces to see if this shoe can move Through the gears plus a few 90minut Very slow plots on very tired legs to See how they feel when you're cruising SL struggling now I said it in the first Run video and I think there's a lot to Like about these shoes you've got the Combination of the knitted uppers and

The plush padding makes for great step- In comfort from the moment you lace them On now there's still quite a lot of shoe On the foot here but that's pretty Standard for shoes in this sort of Higher cushion sort of plusher comfort Cruising bracket that end of the market And having said that I think that Somehow the glycerin 21 still manages to Ride lighter than you'd think when you First look at it and take it out of the Box the ride feels pretty well balanced Overall to me it's definitely soft but Not too too soft there's a good bit of Resilience and return in that nitrogen Infused DNA Loft V3 foam it does a good Job of taking the edge off the road from Your initial cut of impact when you land But it's quicker than some Foams to Compress and then fully return or give You that return so overall the sensation Sort of is happily cushioned but not Overly squishy and labored which I Really like I don't like Foams that sort Of take too long to come back I Definitely think that's helped by the Sort of thicker rubber out soole that You've got here I think stiffens things Up a little bit overall I'd say these Offer good cushion comfort without Veering into being too dull flat sinky Or ponderous what that means in practice Is that I think you can quite happily Tick along at a 7 minute mile Pace or I

Should say I did I could that's kind of Just under my current marathon pace bit Slower but for you know for mid-length Runs it handled that pretty well at that Pace it might not be my first choice for That kind of run but it coped well Enough so there is some versatility here And I'd say it's soft and protective With smooth Transitions and a ride that Doesn't feel too leggy One thing I highlighted in our first run Video as well that I still felt after Subsequently longer runs was that Despite you got a wide kind of midsole Platform here sometimes felt just a Little bit of wobble almost within that Midsole so as my foot was sort of Cradled nicely but I got a little bit of Movement in the Mido that was mainly When I was moving a bit more ragged and Lazy so it's not a huge deal and I Wouldn't say that these are an unstable Shoe but I was aware of it more than in Something like the sakon ride 17 for Example on a positive note though I Thought the grip on this shoe was solid I plowed through some pretty wet and Slippy cobbles and the grip from this Substantial kind of rubber covering was Nicely reliable and so far I'd say you Know early early days but it's showing No signs of sort of wear and tear you Know good durability on this shoe as Well and I think this will be a shoe

That can eat a lot of miles and still be In good condition later into its Use verdict then well this was my first Time running in a glycerin and I was Never 100% sure that the glycerin model Would be a shoe for me in general I Prefer something that's a little less Shoe on the foot I don't tend to go for These kind of big padded thick kind of Plush shoes overall I still kind of Stick with that but after my test miles In the glycerin 21 I've been quite Pleasantly surprised and maybe I'm Getting somewhere along the way to being Converted as an easy low and slow shoe I Think the glycerin 21 offers most of What you need great on the foot Comfort Cushion Landings decent protection for Your feet over longer miles without Feeling overly soft and sinky and too Sort of sluggish for me it avoids that Sensation that you can get from some Shoes where you feel you're trading Softness for immedia so you get that Cushioning but you don't really get the Kind of quickness and lightness in the Step and that means that this shoe has Some versatility to it which I really Like now if you really need to go a bit Faster you can that said it's still not Really a shoe that I'd use for faster Miles I'd only really lace it up for Longer slower plots but if that's what You're after I think this does it really

Well and it would it be my first choice Choice for that still maybe not I think Overall I'd still probably pick a suy Ride 17 or maybe even the oncloud Eclipse over this shoe just because I Think I find them a little snappier and Livelier and I might shoot for the ghost Max for the allout comfort on slower PLS To mainly because it's cheaper but for Me the glycerin 21 does a lot right and I think it will be a happy Workhorse for Plenty of Runners who like things a bit More comfy and Trad so my v on the Brooks Gan 21 is that it feels like a Pretty solid update on the glycerin 20 I Think ultimately if you like the idea of A lighter version of that shoe and a Shoe that kind of takes that midsole Foam and puts more of it under your feet Then that's ultimately what you're Getting with the glycin 21 and it's I Still think it's you know best designed For those kind of shorter long slow easy Recovery style kind of speeds where you Know I think the shoe works best it's Stable protective gives you a little bit Of bouncer to keep things enjoyable as Well too Al you have those kind of Multiple kind of width options there to Make sure you get a good kind of Spacious fit though I think the fit in General is going to be good for most People I think you know from a kind of Cushion shoe point of view definitely ve

Is more on that kind of plush side now So things like the aex Jael Nimbus Things like the new B 1080 v13 as well Too where I think when you look at those Two shoes compared to this I think this Feels most similar to the ja Nimbus Where I think with a 108 v13 you're Getting something that's lighter in Comparison I think you're getting a Nicer rocker there's no real kind of Rocker feel in the shoe to kind of get You a bit kind of nicer and kind of Smoother through those kind of Transitions which just makes it a little Bit easier to maybe run a little bit Quicker in something like the 1080 v13 Where I think with this it's very Similar to the gel nimbers for me now as I said I think it's lost a touch of Versatility about it and I think if you Wanted a more versatile cushion Sho and I think you can have to look at things Like the sakon Triumph range I think Also the P velocity Nitro three as well Too now those fits I would say are a Little bit more restrictive and I think You know not as room as spacious as Things like the Brooks L 21 But Ultimately will give you something that Can work at slower and easy Paces as Well too and still give you that kind of Softer feeling underfoot as well um like You do get on the glycerin 21 so as I Said I think it is a good update I think

If you wanted a sof feeling glycerin 20 One that is still designed best for Eating up a lot of time your fee you Know not necessarily at your quicker Paces and you know using it for your Recovery runs in between your kind of Speed shoes then absolutely can do that Job it's a little bit more expensive is It the best cushion shoe out there is it The best and lightest shoe out there Maybe not but I think if the glycerin Has worked for you particularly gin 20 I Said you want that extra level of Cushioning and something for those types Of runs I've described then I think it's Going to serve you well overall okay so There you have it that is our Multitester verdict on the Brooks Glycerin 21 now hopefully that video has Helped you get a better sense if this is A cushion shoe that you need in your Life now if you've got any questions About this shoe do let us know in the Comments as always like And subscribe Hit that little bell to find out about Latest videos and yeah we'll see you for The next run testers Video