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ASICS Gel-Kayano 31 Review
By Matthew Klein

The Kayano experienced an extreme overhaul as it entered its third decade. Transitioning from a consistent traditional medially posted shoe, the new Kayano featured both stable neutral and geometrical stable elements combined with a unique resilient midfoot block meant to spring the arch into and out of pronation. The result was somewhat polarizing, but the Kayano series has maintained its popularity fitting into today's maximal world. Version 31 makes some subtle changes that refine the upper, increases the midfoot bounce and continues this trajectory as an enlightened premium stability shoe. 

ASICS Gel-Kayano 31
Price: $164.95 at Running Warehouse
Weight: 10.7 oz, 305 g (men's size 9), 9.3 oz, 266 g  (women's size 8)
Stack Height: 40 mm / 30 mm
Drop: 10 mm
Shoe Purpose: Premium Stability Daily Trainer

Pros: Great Combination of Stability/Guidance Features, Bouncy Midfoot Facilitates Appropriate Midfoot Motion, Highly Cushioned, Plush, Comfortable, Smooth Midfoot/Forefoot Transition 
Cons: Heavier Shoe, Slightly Clunky Heel 


The ASICS Gel-Kayano 31 is the continuation of the radically new Kayano series for those who want an excellent premium stability/guidance shoe for easy running, walking and all-day wear. A new slightly thinner upper provides a secure, plush fit while still providing some wiggle room through the length of the shoe. An improved 4D guidance system provides a new system that bounces you into and out of pronation/supination. Although with a wider base and sidewalls, the Kayano 31 provides a combination of stability and guidance that will keep you centered regardless of which way you move. 

: Brooks Glycerin GTS 21, Mizuno Horizon 7

(To learn how a shoe should fit, check out our full podcast on fit by Matt Klein.)

The ASICS Gel-Kayano 31 fits me true to size in my normal men's US size 10. The width is normal to slightly wide throughout the length of the shoe. The volume is normal with extra wiggle room height-wise in the forefoot. The upper mesh is slightly thin but plush all throughout. This allows for extra stretch up at the forefoot, which is already slightly wide. There is a slight taper at the toe box, which has a thin toe guard. This transitions into a normal to slightly wide midfoot. The tongue is moderately thick and well-gusseted. The laces easily lock the shoe down and I did not have to tighten them much to get a secure fit. The heel is normal in width with a ton of heel collar cushioning. The heel counter is thin slightly flexible. Those with haglund deformities or heel sensitivities should do fine given the amount of padding in the rear except for those with extreme sensitivities. The inner liner is extremely comfortable and can tolerate sockless running. There are some internal seams that can cause rubbing over longer distances, so only those with experience running without socks should consider doing so in the Kayano 31. The security is quite good for the slightly wider fit. I have not had to do a lace lock at any point. The slightly thinner but plush material does allow some airflow up front, making for a well-balanced, comfortable, premium upper. 

Typical Size: Men's US Size 10
Shoes that have fit Matt well: Saucony Guide 17, ASICS Kayano 30, Hoka Gaviota 5, Saucony Endorphin Elite, Nike Ultrafly
Shoes that have fit snug: Hoka Arahi 7, Saucony Kinvara 14
Shoes that have fit large: Salomon S/Lab Phantasm 2, Altra Timp 5

Doctors of Running Checklist

Is This a Good Shoe for Walking: Yes
Is This a Good Shoe for Standing: Yes
Is the Forefoot Flexible: No
How Flexible is the Shoe: Not Flexible
Is This a Good Heel Bevel: Somewhat
Recommended for Haglunds: Mild sensitivity users fine
Recommended for Sockless: Maybe
Durability Expectation: Above Average


The ASICS Gel-Kayano 31 is a premium stability shoe that works best for easy mileage running, walking and standing. The stack height continues to be maximal with 40mm of stack in the forefoot and 30mm in the heel. The 10mm drop is somewhat noticeable due to the larger heel although the compression of the softer FF Blast+ midsole takes some of the edge off. The midsole is soft and highly cushioned throughout the length of the shoe. It is not unstable but provides high-quality cushioning that maintains its feel even over longer efforts. The paces this shoe works best for are easy and longer efforts as the higher weight of the shoe prevents it from doing anything even remotely up-tempo. There is still some bounce from the midsole, mostly originating from the medial piece of resilient foam (part of the 4D guidance system) in the midfoot that provides a noticeable pop out of the midfoot.

The heel is a little clunky at first despite a small posterior lateral bevel. This is due to the posterior flare, although the geometry of the heel compresses better the more the midsole breaks in. The PureGel heel also adds to some additional compression and softness, which does help the heel transition. This moves through the bouncy midfoot and into a smooth, rockered forefoot. There is little flexibility to the sole, so those with toe mobility issues should do well here. The rocker starts early and is somewhat gradual, making this shoe even more tuned for slower, comfortable efforts.

The outsole traction is quite good on both dry and wet road. The Kayano 31 can handle some mild trail, but is mostly meant for firmer terrain. The durability is great as I have 40 miles on my pair with almost on wear on the outsole. Thus I expect to get a ton of miles out of the Kayano 31 just as I have out of prior models. 

(Learn more about stability in our full guide)

The ASICS Gel-Kayano 31 is a shoe that combines all the latest concepts in guidance and stability. The base is wide throughout the length of the shoe, especially in the midfoot. This is widened even farther thanks to sole flare on the medial and lateral sides of the shoe. There are large sidewalls in the medial heel/midfoot and the lateral heel. The arch and 4D guidance system is a little higher than the previous version. Those who like a mild post like feeling will do well in this shoe. Those who want a major post like feel will not do as well as the Kayano now focuses on keeping the foot highly centered throughout the length of the shoe. There is internal geometrical guidance built into the midsole. This provides noticeable resistance to excessive medial or lateral motion. I do not feel pushed one way as I often do in other stability shoes thanks to the central guidance theme that the Kayano uses.

The most interesting stability component to the Kayano 31 is the more resilient 4D guidance foam in the midfoot. This is a more resilient and bouncy foam than the FF Blast+ used in the rest of the midsole. This material has a large amount of bounce and facilitates a dynamic and controlled pronation to supination transition at the midfoot. This is not a post-like feeling but a facilitation and bounciness that helps you get out of end-range midfoot pronation. This is incredibly smooth and far more noticeable than the previous version. So those who do not do well with aggressive posts and instead want a bouncy and smooth transition through the midfoot with a stable heel and forefoot will do best in the Kayano 31.

Thoughts as a DPT: Biomechanics of the Medial Longitudinal Arch and Pronation
By Matthew Klein

The 4D guidance system in the Kayano 30/31 replicates the true function of the arch far more than traditional medial posts. Most of the thought process behind medial posts was to create a harder medial material that the foot was thought to either move away from (path of least resistance) or to "support" the arch by holding it. Both these concepts certainly reduce symptoms and work for some people, but the efficacy behind either of those statements may not apply to everyone. To truly understand why the idea of a softer and more resilient foam in this area may also work instead of the traditional opposite found in medial posts, we need to understand the medial longitudinal arch and what pronation really is. 

The medial longitudinal arch is made of all the bones on the medial side of the foot, including (but not limited to) the first metatarsal bone (long bone), medial cuneiform, navicular, talus and calcaneus. There are multiple connections between all these bones and those lateral to them, which means the medial longitudinal arch is made of many joints and not just one (ie only eversion/inversion). The main function of the arch is to be able to collapse to absorb shock and elevate to stiffen up. Both variations need to occur at different times to achieve either mobility or stability depending on the relevant task requires. 

The "collapse" is often called pronation, which involves the combined movements of these joints and more, is used to collectively describe the medial dropping of the medial longitudinal arch. This specifically describes the motions related to this, specifically eversion, abduction and dorsiflexion of the ankle and foot. This does not describe a pathology as pronation is a normal movement. Pronation typically occurs after the initial contact phase of walking and running where the foot makes contact with the ground. This next phase is called the "loading phase" during which the body absorbs the shock of landing. Each part of the lower extremity has its own way of absorbing this shock. The foot/ankle normally use pronation as a way to absorb the impact that occurs during this phase through various muscles, joints and soft tissue structures. As the individual reaches their maximum level of pronation during midstance (the body is directly over the foot), the pronation movement of the foot shifts toward the opposite direction, or supination. The reason for this is that pronation serves to make the foot more mobile for shock absorption, while supination stiffens up the foot for propulsion. The second half of the stance phase (foot on the ground) of gait involves the propulsion of the body forward (especially during running). During this phase, in order to create a stable area to push off from, the foot/ankle must resupinate in stiffen the foot up. The smoother the transition between pronation and supination, the more efficient this system works. Stopping it completely is not a long term solution as it is a normal part of shock absorption and propulsion. Those who do not pronate enough can actually have an increased risk of certain types of injuries while those who pronate too much may have an increase risk of other certain injury types (Hetsroni et al., 2008)

Therefore, the understanding that this is a dynamic movement/system and not a static supports the new system from ASICS in the Kayano to help elastically bounce/facilitate appropriate pronation rather than completely stopping it. There are other elements that provide excellent forward guidance, but long term, pronation is a motion that should optimally be controlled and utilized as an advantage, rather than labelled a pathology and eliminated. This is a movement control issue and people should be taught how to control it for their own benefit in shock absorption. Taking it away may comprise that ability in many ways. 


Hetsroni, I., Finestone, A., Milgrom, C., Ben-Sira, D., Nyska, M., Mann, G., ... & Ayalon, M. (2008). The role of foot pronation in the development of femoral and tibial stress fractures: a prospective biomechanical study. Clinical Journal of Sport Medicine18(1), 18-23.

Jacquelin Perry, M. (2010). Gait Analysis: Normal and Pathological Function. New Jersey: SLACK.

Neumann, D. A. (2016). Kinesiology of the Musculoskeletal System-E-Book: Kinesiology of the Musculoskeletal System-E-Book. Elsevier Health Sciences.


The refined upper and increased midfoot bounce are great improvements to what is arguably the best the Kayano has ever been. The midfoot bounce especially brings to life what I mostly missed and misunderstood in version 30. The stable ride that will work for a variety of people with stability needs is excellent and continues to execute all the guidance concepts we have been talking about at Doctors of Running. My two major suggestions continue to be a decrease in weight and an improvement in the heel bevel. The weight is standard for what this class of shoes as the Kayano 31 is the same weight as the Glycerin GTS and is similar to the Horizon 7. However, ASICS has the full capacity to lower the weight, which would improve the Kayano's efficiency, especially over longer mileage. The heel is marginally better than the prior version, but the continued use of a flare and "crash pad" still makes this shoe slightly clunky. The current bevel is placed well but needs to be a little larger to be more effective in modeling the curved human calcaneus. 


The ASICS Gel-Kayano 31 is for those who want a high level guidance/moderate level stability shoe that uses newer concepts, including a bouncy midfoot, to provide support for easier and longer runs. The ride continues to be maximal with a 10mm drop and a rockered from the midfoot to the forefoot. Those that land a little forward or are ok with a slightly early initial heel contact will like the ride best. The fit is normal to slightly wide with an adaptive fit that shoe work for a variety of normal foot shapes with additional widths available for those that need more room. The function will work best for those wanting a walking shoe, all-day standing shoe or easy mileage shoe. This daily stability workhorse will continue to be a popular model among those looking for comfort and guidance.


Fit: (Comfortable fit with slightly breathable and plush upper that works for both walking and running)
B/B+ (Highly cushioned daily training shoe for mileage. A bit on the heavy side)
Stability: A [Moderate Stability/Guidance] (Wider sole, wider midfoot, sidewalls, geometric stability and midfoot facilitation make this a moderate stability shoe and a higher level guidance shoe)
Value: A- (For the durability and progressive stability, this is a great value shoe)
Personal: B+/A- (My top running and walking stability/guidance trainer of the year. Still a bit heavy but excellent execution in a shoe that deserves to be popular)
Overall Design: A- 


ASICS Gel-Kayano 31
Price: $164.95 at Running Warehouse

Shop Men | Shop Women

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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, Santa Barbara, Danbury and Stevens Point areas, we 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 ASICS for sending us pairs.  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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