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Brooks Beast/Ariel GTS 23: The Biggest and Baddest Stability Shoe
By Bach Pham and Matt Klein

The Brooks Beast/Ariel series are now the longest-running motion control shoe series. For a moment, we thought they might disappear as version 20 remained un-updated until recently. It outlasted others like the Asics Gel Foundation, Mizuno Wave Alchemy and many more as extreme stability shoes disappeared. Its close cousin, the Addition, remains the only other major motion-control shoe on the market and current plans for an update or continuation remain unknown (we probably should just ask our friends at Brooks what the plan is instead of acting mysterious). Regardless of the series age, there have been a solid balance of changes and consistency. It retains its highly rigid ride and high drop while gaining softer cushioning and a better upper, continuing an extremely slow progression forward while being one of the sole remaining motion control shoes.

Brooks Beast (Ariel) GTS 23
Price: $159.95 at Running Warehouse
Weight: 11.9 oz, 337 g (men's size 9), 10.7 oz, 303 g  (women's size 8)
Stack Height: 26 mm / 14 mm (not including insole)
Drop: 12mm
Classification: Max Stability/Motion Control Daily Training Shoe


Matt: The Brooks Beast/Ariel GTS 23 is a heavy-duty motion-control shoe for walking and easy mileage. A wide sole, straight last, extremely stiff ride and large GuideRails make it an excellent option for those that need as much stability as possible. A new DNA Loft V3 makes for a cushion ride, particularly in the heel with the continued 12mm drop. A new upper addresses the creasing of the previous version, balancing comfort and security up top. While this is a little different from your parent's Beast/Ariel, this series continues on as a cushioned motion control shoe for those needing a high drop and as much stability/sole stiffness as possible.

Bach: Once a more crowded market, the high level stability shoe has become a market of one (1.5 if we're being technical) with the Brooks Beast (Ariel being the women's version). The massive GuideRail system is very present from front-to-back, providing a large amount of motion-control for the runner. While the DNA Loft v3 midsole is nicely cushioned, a slappy forefoot makes for a bit of a rough ride. Those who are looking to ease back into running or a significant amount of control will find the Beast as the premier option in terms of raw stability.

: Brooks Addition GTS 15


Matt: The Brooks Beast GTS 23 fits me true to size in my normal men's US Size 10. The overall varies with a normal width forefoot, snug midfoot and a little wider heel. The toe box tapers somewhat quickly with a wider forefoot. This initially made this shoe feel slightly short but after a few miles broke in well. The midfoot is snug enough that I did not have to tighten the laces at all for a secure fit. The tongue is strongly gusseted on the medial side and the wrap was noticeable on my arch. The heel fits a little wider with a surprisingly flexible heel counter and a ton of heel collar cushioning. Those with sensitive heels may have some issues but I was extremely surprised that I did not. Despite the wider heel, I did not have any heel slippage likely due to the snug midfoot. The inner mesh is quite comfortable and while is could be worn sockless, I would approach with caution due to the reinforced mesh material at the toe box. So socks are advised. 

Bach: I found the Brooks Beast GTS 23 to fit comfortably throughout. There is a normal amount of width in the forefoot and a secure midfoot that provides a good lockdown. The shoe is best for standard to narrow feet as is. The Beast/Ariel does, however, come in 2E wide and 4E wide for those who need more width. I could wear both thin and thick socks alike and felt fine in this model. There's ample room in the heel to fit the shoe in comfortably while the laces doing a good job of making you feel secure. The security of the shoe's lockdown felt plenty confident. The Beast is slightly bucket-like with the GuideRails slightly sitting above the foot making you feel locked in. There are overlays that add a lot of structure to the upper. The heel is fairly padded and comfortable, giving a bit of a premium feel to the shoe. I did not have any issues with breathability despite how much shoe there is which did surprise me. Overall I felt like the Beast does a good job providing both security and a quality fit.


Matt: The Brooks Beast GTS 23 is a heavy, stiff motion control shoe meant for easy miles and walking. The new DNA Loft v3 does provide a large amount of cushioning underfoot. The foam is compliant, meaning it compresses quickly and firms up quickly. This gives it a brief feeling of softness at loading followed by a firm and grounded feel immediately after and throughout the rest of the stance phase (foot on the ground). The majority of cushioning is centered at the heel thanks to the higher stack height and 12mm drop. This makes for cushioned heel landings and a bit firmer forefoot transitions. There is some mild flexibility to the forefoot, making for a decent transition off the front of the shoe. The heel transition is balanced by a small heel bevel and foam that compresses with the 12mm drop and weight being centered back toward the rear. This does make for a slightly clunky heel transition that feels better walking than running.

Purpose-wise this shoe can only handle walking and slow running. The 11.9 oz weight is noticeable, but decent a 0.2 oz weight increase, it still rolls and moves a little better than the GTS 20. This is not a shoe meant to pick up the pace or do anything but slow running. Fortunately with its tank-like mobility comes excellent durability. I have 20 miles on my pair and the outsole has no wear on it. I have only used this shoe road as the traction is meant for smoother surfaces. However, the thickness of the outsole will likely do fine on smooth dirt surfaces. 

Bach: This shoe is all about taking it nice and slow. I found the shoe to be best not at my easy paces (roughly 10 min/mi), but at my easy easy paces (11-12 min/mi). Whether you want to call it a plod or a jog, the shoe excels at very slow and easy running. Going at my relative normal everyday pace felt like a grind trying to turn the shoe over, but when I accepted what the shoe was best at, I was able to enjoy it a lot more. It does feel best when you are on your mid-to-forefoot and off the heel as the transitions in the rear are not smooth. I also didn't enjoy opening up my stride in the shoe as the forefoot rubber pattern is very dense and  pronounced when striking the ground, creating a fairly significant slapping feeling when struck. The DNA Loft v3 midsole itself is moderately comfortable, but the blown rubber outsole firms the shoe up a good deal on landing.

Speaking of outsole, there is a dense amount of it throughout that provides good traction which comfortably handles road, wet surfaces and even mild trail just fine. I took the shoe through some grass and dirt roads and it did well enough, but definitely excels at road where it was intended.

As a walking shoe, I found it to be okay. It does feel like lot of shoe on foot at just under 12 oz, especially in the rear, but the shoe otherwise does provide both comfort and a high level of stability for people who do want a very stable, supportive shoe. I particularly found it to be a good standing shoe thanks to its width and supportive nature.


Matt: The Brooks Beast GTS 23 is a motion-control shoe. The base of the shoe is extremely wide, particularly in the heel and midfoot with a large amount of sole flaring in the heel. The ride in the heel and midfoot is incredibly stiff, adding a high level of resistance to lateral motion. The large GuideRails on the medial and lateral side are noticeable as soon as you start moving, providing aggressive central guidance. While standing they were not as apparent and the stiffness of the sole was more noticeable. As soon as you start to move and roll either direction, the aggressive control immediately becomes apparent. The majority of this stability is centered at the heel, is still apparent at the heel then tapers off a bit at the forefoot. The forefoot is still wider, but it more natural (relative term) than the rest of the shoe. Therefore, those with extremely high and high stability needs in the heel and midfoot, respectfully, will do best in this shoe.

Bach: The Brooks Beast features a large, extensive GuideRail that goes from the rearfoot to nearly the forefoot medially, with an additional GuideRail laterally in the heel. The Beast's features the most noticeable use of GuideRails I have ever experienced, with the rail leaning slightly against your foot on the move and working to keep you very centered. This is where going slow and easy made the shoe feel best as pushing a bit faster starts bringing the GuideRail more and more into play which I found to be a bit too controlling my own needs. On top of the GuideRails is a modest amount of sole flaring, a lot of width, and the upper again does good job of keeping the foot secure and in place. The shoe has a bit of a bucket-like feel on foot due to the GuideRails running slightly above the foot, adding to the guidance.

Due to the lack of integration of anything intrusive directly under the foot, I was pleasantly surprised to find my flat feet to be comfortable in the shoe with the guidance being more of the challenge for my own needs.

These elements together help provide a high level of security throughout that is apparent from the second you slip on the shoe. The Beast GTS 23 is clearly for individuals who have the highest level of stability needs, and not for anyone with very mild stability needs or neutral mechanics.

Thoughts as a DPT: Death of the Motion Control Shoe
By Matthew Klein

There has been a notable decrease in the number of stability shoes in recent years. Light stability shoes like the Adidas Tempo, Mizuno Wave Catalyst, ASICS DS Trainer and more have ceased to exist. Moderate stability like the Brooks Adrenaline, ASICS GT 2000, Saucony Guide and others have continued thanks to clear popularity and demand. The last major category, motion control shoes, known for having the highest level of stability have almost completely ceased to exist. Motion control shoes are (were) usually characterized by being heavy, extremely stiff torsionally, featuring massive posts or stiffening agents and thick uppers. They were commonly sought by those needing (or being told they needed) as much stability as possible.

The industry as a whole has shifted toward less stability and more guidance-based footwear. Many of the medial posts have disappeared in favor of guide rails, sidewalls, guidance lines, midsole geometry and more. This was partially motivated by a change in understanding of foot mechanics, fueled by the concept of the Preferred Movement Paradigm and central guidance rather than forcibly correcting every foot the same way (Nigg et al., 2017).

Motion control shoes, for the most part, did not fall into the central guidance idea and were mostly known to overly correct mechanics in a certain direction. Additionally, there was mixed evidence as to whether motion control shoes or posts actually corrected motion or if they simply slowed down movement and the foot moved the same amount (Cheung et al., 2011). There were many studies that certainly showed that they could, while others suggested that the foot was continuing to move inside the shoe and being missed by motion cameras. 

Combining the fact that these shoes were generally extremely heavy and not the most comfortable, it was not surprising to see many disappear. To see all but one or two disappear was surprising. The Brooks Beast/Ariel and Addition are the lone motion-control shoes on the market. They do feature more progressive methods of stability, with GuideRails present and the continued use of wide straight lasts, torsional stiffening agents, sole flare, etc. Despite not being a common shoe, they still certainly have a place for a small portion of the population. The ability to buy a shoe that does not require the additional purchase of an expensive orthotic is great, especially for those who are so used to this series. They are certainly people who have excessive and poor movement quality in the rear and midfoot that may benefit from these shoes. Many people would benefit from extensive rehabilitation and strengthening but not every person's body can do that. It is important that everyone be given the opportunity to move, exercise and ambulate. If that requires a Brooks Beast/Ariel, so be it. Shoes are tools and some people will require some extreme ones, but if that is what it takes to stay moving, then by all means get them in that shoe. Essentially Brooks, I am begging you to continue making this shoe as there are still many people whom it benefits, even if it isn't the whole or even a decent number of the population. Everyone should have the opportunity to move, regardless of their footwear needs. 


Cheung, R. T., Wong, M. Y., & Ng, G. Y. (2011). Effects of motion control footwear on running: a systematic review. Journal of Sports Sciences29(12), 1311-1319.

Nigg, B. M., Vienneau, J., Smith, A. C., Trudeau, M. B., Mohr, M., & Nigg, S. R. (2017). The preferred movement path paradigm: influence of running shoes on joint movement. Med Sci Sports Exerc49(8), 1641-1648.


Matt: This Beast/Ariel is different than the version I used to help people try on in running stores over a decade ago. The use of guide rails instead of overly aggressive posts is a major step forward. It is an aggressive stability and guidance shoe, but it is still really heavy. While the DNA Loft v3 does take some of the edge off the weight, I would love to see this shoe a little lighter. While sub 11 oz may not be possible with the focus on this shoe, I would love to see it down to low 11 ounces. Large guidance lines in the outsole could easily drop some weight and provide additional directional control. Another option would be lower the heel, which would also offset the weight bias toward the back. For being one of the rare shoes on the market in this category, I would be careful with changes. This is not a mainstream shoe, so the population using it will be quite different from the majority of runners.

My last suggestion would be to consider adding a little more volume to the forefoot. I understand the prior version had some issues with creasing, but it is important that there is enough room in the forefoot, especially in such a stiff stability shoe. This should not be sloppy, but it would be helpful to not have the toe box taper so much for toe comfort.

My main recommendations focus on the ride of the shoe. The weight of the Brooks Beast GTS 23 feels fairly loaded in the rearfoot, not surprising considering the GuideRails there. Finding a way to take some weight out of the heel, particularly with a lighter foam would be helpful in making the shoe feel a little more nimble. The forefoot outsole could also use a less aggressive, smoother design to reduce the slappy nature of the ride in its current form.

I would like to see the shoe remain a high level of stability for runners to have the option and I am glad - even though it's not a perfect shoe by any means - to see that it exists for runners who do benefit from it.


Matt: The Brooks Beast or Ariel GTS 23 is for those who want a rare motion-control shoe with a large amount of protection, aggressive central guidance and a secure midfoot. The guide rails, wider base, stiff sole, and other mechanisms provide aggressive stability primarily in the heel and into the midfoot. Those who want this to happen more during running/walking and less overtly during standing will do best. The fit is normal with a little toe box taper, decent forefoot room a snug midfoot and a wider heel. While a bit old school category wise, the Brooks Beast/Ariel does bring some upgrades over the year. Additionally, it provides a rare shoe in this category for those that need it.

I do think this shoe is necessary to keep on the market given how small the category is. Not everyone will need or be able to tolerate a shoe like this but it should stay on for the small population, be it due to orthopedic, neurologic, genetic, etc reasons to help maintain the ability to tolerate gait. $160 isn't bad with how expensive shoes are now, but I would encourage Brooks to try to keep that down given those looking at this shoe may also be coming from spending high amounts on medical bills. That is an assumption and may not always be true, but accessibility is extremely important for those coming to this series with significant impairments that need support.

The Brooks Beast remains one of the last shoes in the market to provide an extremely high level of stability. It is a good shoe for embracing slow jogging along with stable walking. It's also as durable as can be. The Beast is definitely a niche shoe that runners who want stability should definitely try on first to see if it is too much or just right for their needs. Visit our stability guide to learn more about how you can determine that for yourself.

When looking at the rest of stability options right now, the most comparable consideration to the Beast that comes to mind for me is the Mizuno Horizon 6 which feels like a slightly more balanced version of the Beast weight and cushioning-wise, but with milder level of stability. If you like the guidance of the Beast, but in a lighter and more milder package, the Brooks Adrenaline GTS 23 or Hoka Arahi 6 are good alternatives to consider.


Fit: B+ (Secure fit with locked in midfoot. Toe box tapers a bit and heel counter is surprisingly flexible for a motion control shoe)
Performance: C
 (Slow heavy shoe meant only for walking and slow running. Nothing uptempo or fast should be attempted)
Stability: A [Motion Control] (Aggressively stiff heel/midfoot with large guide rails, sole flaring in heel and wide base)
DPT/Footwear Science: B (Somewhat updated thoughts on motion control but still heavy. Could benefit from additional and newer methods to at least reduce weight)
Personal: C- (I appreciate what Brooks is trying to do, but I cannot handle running much in this shoe as it has far too aggressive stability for me. Walking is fine. This is not an appropriate shoe for me for running as my stability needs are not that high)
Overall: B- 

Fit: A- (Fairly easy, comfortable-fitting shoe all-around)
Performance: C
(Severe lack of versatility, limited to walking and slow runs)
Stability: A+ (The highest level of stability available in the market for runners today, particularly medially)
DPT/Footwear Science: B- (The innovation feels limited, but the shoe existing is still important in itself)
Personal: C (A really hard shoe for me to dig a lot of miles into personally for the level of stability)
Overall: C+/B-


Brooks Beast (Ariel) GTS 23
Price: $159.95 at Running Warehouse

Shop The Beast | Shop the Ariel

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Asics GT-1000 11 - The most affordable stability shoe in the market
ASICS GT-2000 12 - A new 3D guidance system provides cushioned, modern stability
Asics Kayano 30 - Big changes bring Kayano into the future, creating a geometric stability option
Brooks Adrenaline GTS 23 - The long running stability trainer stays true with small changes
Brooks Hyperion GTS - All-new, lightweight stability offering using guidance
Hoka Gaviota 5 - Hoka moves to a new H-Frame stability that universalizes the Gaviota
Mizuno Wave Inspire 19 - The redesign for the guidance-based stability trainer is an early 2023 favorite
On Cloudflyer 4 - An update to the mild stability trainer (a really solid walking shoe)
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Editor's Note: As always, the views presented on this website belong to myself or the selected few who contribute to these posts. This website should not and does not serve as a replacement for seeking medical care. If you are currently injured or concerned about an injury, please see your local running physical therapist. If you are in the Los Angeles area, I am currently taking clients for running evaluations.

***Disclaimer: These shoes were provided free of charge in exchange for a review.  We thank the people at Brooks Running for sending us a pair.  This in no way affected the honesty of this review. We systematically put each type of shoe through certain runs prior to review. For trainers and performance trainers, we take them on daily runs, workouts, recovery runs and a long run prior to review (often accumulating anywhere from 20-50 miles in the process). For racing flats we ensure that we have completed intervals, a tempo or steady state run as well as a warm-up and cool down in each pair prior to review. This systematic process is to ensure that we have experience with each shoe in a large variety of conditions to provide expansive and thorough reviews for the public and for companies. Our views are based on our extensive history in the footwear industry and years testing and developing footwear. If you are a footwear rep looking for footwear reviews or consultations on development, we are currently looking to partner with companies to assist, discuss and promote footwear models. Partnership will not affect the honesty of our reviews.

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Hoka Gaviota 5

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