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Karhu Ikoni 2022 Review:
The Finnish Trainer
By Senior Contributor David Salas and Contributor Andrea Myers

The Karhu Ikoni is a neutral daily training shoe that utilizes a 1/2 length fulcrum through the midfoot to help give some guidance and responsiveness to the ride of the shoe. The Ikoni in the past has traditionally had a slightly firmer profile with a slightly beveled geometry throughout. Much of the same formula is seen in the 2022 veresion though, with some small adjustments that enhance the ride of the midsole and fit of the upper throughout. The Ikoni also comes in a HiVo option for those that may require a little more volume through the upper or space for wider foot accommodation.

Price: $140
Weight: 9.6 oz, 272g (men's size 10), 8.0 oz, 226 g  (women's size 8)
Stack Height: 26mm heel/ 18mm forefoot
Drop: 8 mm
Classification: Neutral Daily Training Shoe


David: The shoe falls in what we say is a "stable neutral" shoe for many. The Ikoni provides a gently beveled ride, good ground feel throughout, as well as a fulcrum through the rearfoot and midfoot to help with some guidance and mild stability needs. The shoe utilizes the new AeroFoam that makes the ride a little softer than the previous iteration. The result is a protective yet still relatively firm riding shoe that has a nice blend of a rocker geometry and traditional training shoe. Though not overly responsive, the shoe provides a consistent and pleasant ride for those that like a slightly firmer platform.  

Andrea: Karhu is a Finnish running company that has been making shoes since the early 1900s. Emil Zatopek won 3 gold medals in the 1952 Olympics in Karhu shoes. Shortly after the Olympics, Karhu sold their original 3 stripes trademark to another athletic shoe company, which still uses it today. In 2018, Karhu developed Ortix Fit with data from over 2 million foot scans in partnership with Fleet Feet using their FitID technology. Ortix Fit specifically refers to Karhu’s unique midsole geometry, upper volume, and last. Karhu claims that Ortix Fit gives their shoes a near custom fit right out of the box. I had never heard of the Karhu brand before the shoes showed up at my door. The rocker design and wide forefoot intrigued me and I was excited to give the Ikoni a try.

The Karhu Ikoni is a neutral trainer with a half-length rocker that Karhu calls Fulcrum. The Fulcrum promotes a very smooth ride and the wider forefoot allows for comfortable toe splay. I found the AeroFoam cushioning on the firmer side, but it has softened a little with every run. The Ortix Fit is near perfect for me and the upper is incredibly comfortable. I have thoroughly enjoyed testing this shoe and expect to put many more miles on it.


David: Full disclaimer: I received the HiVo version. The HiVo version is normally for someone who requires a little more room for foot accommodation whether it be actual volume vertically or through the width of the shoe. Despite being in the HiVo version I did not have any problems with fit as long as I tightened the laces down accordingly. The materials of the upper are still done really well with a nice sock like mesh that wraps around the foot. The tongue is a little more padded in the second version and allows for you to lace the shoe down tightly without any irritation. The width through the heel and midfoot is normal and the upper does a good job of locking down through that region. The forefoot is slightly wide and does good with toe splay and swelling accommodation. A lot of the pieces of the upper feel like a premium shoe upper but still doesn't quite hold all of the weight that comes with one. There is a moderately rigid heal counter that wraps around the rear foot that is padded very well. The lacing system is also slightly asymmetrical and does seem to help with locking the shoe down a little better, at least in my HiVo option. Overall I am very pleased with the upper of the Karhu Ikoni. 

Andrea: The Ikoni fit perfectly in my usual women’s 9.5. The fit of the shoe is very secure thanks to the mesh upper and a fairly rigid external heel counter that has just the right amount of internal padding. This is the type of shoe that I could tell fit well before I tied the laces. The forefoot is wide enough for comfortable toe splay without allowing foot translation inside the shoe. I found the M-lock lacing system very comfortable and did not require any special lacing techniques to achieve proper lockdown. The upper fits so well that the laces do not need to be excessively tightened to achieve proper lockdown. The M logos on either side of the midfoot provide some structure to the mesh upper and likely contribute to the security of the upper. The lightly padded and gusseted tongue is very comfortable and secure. This is one of the best fitting shoes I have tested.


David: When I run in the Karhu Ikoni, it is like running with an old friend. The ride is smooth and pleasant and not much has really changed. The shoe doesn't feel like it is out to do more than what it was designed for. The shoe is supposed to balance right in the middle with cushioning, responsiveness, and guidance and it feels like it checks all of those boxes. Similar to the previous Iknoi the ride does lean on the firmer end, but does ride slightly softer now. The shoe is gently beveled through the heel and forefoot creating a small rocker that is efficient enough to work but not necessarily feel like you are constantly rolling forward. The overall design is slightly rigid through the heel and midfoot, with moderate flexibility through the forefoot thanks to some flex grooves. The shoe does have a crash pad in the heel and a midline groove showing the fulcrum underfoot. The fulcrum certainly helps maintain the geometry and ride of the shoe while giving slight linear guidance forward from the heel through the midfoot. The foam still leans relatively firm but is cushioned enough for all daily training needs. The ride also feels pretty grounded as the heel stack is only 26mm.

Overall, the shoe does feel like it leans right in the middle with cushion, guidance, and propulsion. There isn't anything overly flashy with the ride of the Ikoni but it gets the job done and it is reliably consistent in maintaining its ride mile after mile. For those that like a slightly rockered ride but still want to feel grounded and have some traditional training shoe elements the Ikoni does a pretty good job with that. 

Andrea: The Fulcrum technology and firm cushioning of the Ikoni make it a comfortable, reliable daily trainer. For recovery runs, the Fulcrum and responsive cushioning help with turnover and ease the load on tired legs and feet. The AeroFoam cushioning is definitely on the firmer side, but the midsole has softened some with every run. It is not as soft as the Saucony Endorphin Shift or even the Hoka Rincon, so some runners may find the Ikoni too firm for daily miles. Softer foam would definitely improve the ride of the Ikoni. The shoe did well with short strides, but it is too stiff and heavy for intervals. The rockered sole makes the 8mm drop feel more like 4-6mm, and the transition from initial contact to push off is incredibly smooth and stable due to the wider midfoot and rocker. The outsole shows minimal wear after 40 miles and I would expect to get greater than average mileage out of this shoe.


David: The Ikoni certainly falls in the "stable neutral" category we at DOR talk about frequently. The shoe does not use any posting or dual density midsoles, but does utilize a plastic fulcrum through the midsole in the rearfoot and midfoot. The fulcrum creates some inherent rigidity and helps maintain the slight rocker geometry and provides a guiderail like sensation throughout the shoe. The shoe also has a relatively wide platform underfoot through the forefoot with some sole flaring and the increased cross sectional area feels good and trustworthy when landing on it. The ride through the Ikoni feels very balanced and stable without using a full length fulcrum or any posting and a lot of that is thanks to the geometrical configuration and midsole composition. The stack is also relatively low and the outsole traction is pretty decent as well. This gives the shoe a good sense of ground feel in combination with the things noted above. Overall, the ride of the shoe of the Ikoni is very stable underfoot for a shoe that is not classified as a stability shoe. 

Andrea: The Ikoni is a neutral shoe, but the rockered sole and wider midfoot and forefoot provide some nice guidance and mild stability. The Ikoni provides an excellent example of how a shoe may be dynamically stable without having any traditional stability features. The significant heel bevel promotes a quick transition from initial contact to midstance for heel strikers, and the early toe spring and lateral sole flare at the midfoot promote a similar quick transition for midfoot strikers. The wider midfoot and forefoot also provide some stability during midstance and push off. I was not specifically aware of the Fulcrum providing any stability to the shoe; rather, I perceive the rocker and sole flare as providing most of the shoe’s stability and guidance.


Unique Neutral Stability, by David Salas
Stability can be created in many different ways. One thing that Karhu has been doing in their footwear is taking a look at guidance and the integration of the midsole as it creates a pathway for the foot to take in stride rather than static rigidity or posting. A lot of other companies are beginning to look into this method as well. With the Ikoni specifically, the shoe is meant to be a balanced shoe that can do a little bit of everything (as well as guidance). The shoe uses a plastic fulcrum through the rearfoot and midfoot that looks a little bit like an H with the upper half of the letter filled in slightly. The shoe provides a crash pad like design in the rearfoot and then gives some rigidity and guidance along the medial and lateral aspect of the heel and midfoot. Assuming our foot takes the path of least resistance, the foot will follow that midline pattern where the fulcrum is not filled in. In the Ikoni this feeling is noticeable and the crash pad design in the heel/midsole is also done well to ease that transition onto the rigid structure. The forefoot is mild to moderately flexible upon load as well. The result is a nice stable ride through the heel and midfoot with a forefoot that lets you do what you want with the shoe. This combined with a gently rockered sole creates a geometry that gives you some new age elements as well as a traditional feeling daily trainer especially through the forefoot. This is something I feel Karhu did very well in the Ikoni with midsole configuration. This is what we call a "stable neutral" training shoe.

The Benefits of Forefoot Width, by Andrea Myers
One of my favorite features of the Karhu Ikoni is the wider toe box. I consistently find that shoes that are too narrow across the ball of my foot cause plantar fasciitis-type pain. In a previous review of Topo,  I wrote about a possible link between shoes that are too narrow across the forefoot and plantar fasciitis (due to the abductor hallucis muscle being placed on stretch, resulting in decreased blood flow through the lateral plantar artery, which supplies the plantar fascia). Today, I would like to discuss a potential link between hallux valgus (a condition in which the big toe points towards the second toe, which often results in a bunion) and patellofemoral pain. 

It is well-established that people who regularly wear shoes that are too narrow across the forefoot are at increased risk of developing hallux valgus (Ray et al 2019). Researchers at Northumbria University examined the relationship between hallux valgus and knee and foot motion during running (Stoneham et al 2020). They specifically looked at whether runners with an increased hallux valgus angle (big toe angled towards the second toe) demonstrated increased pronation and/or knee frontal plane motion (which is side to side motion of the knee, also known as varus or valgus). They assessed 15 runners (10 male, 5 female) as they ran barefoot over a 20 meter runway for gait analysis using 14 optoelectronic cameras. The authors stated they used barefoot running to allow proper visualization of the great toe during the running trial. Prior to the run trial, the subjects underwent full static anthropometric analysis, including lower limb structure and alignment. To habituate the subjects to barefoot running, each subject completed a 30 minute warmup run prior to the 20 meter runway trial.  

The researchers found a strong association between hallux valgus angle and knee frontal plane motion during running. For every 1° increase in hallux valgus angle, there was a 0.24° increase in knee frontal plane motion. There was also a strong association between an increased hallux valgus angle and increased pronation. Research is mixed regarding the relationship between increased pronation during running and patellofemoral pain. Additionally, motion control shoes have not been found to reduce patellofemoral pain in runners (Cheung et al 2006). Previous studies have found a relationship between increased knee frontal plane motion and patellofemoral pain (Nakagawa et al 2012, Dierks et al 2008).

From a biomechanical perspective, hallux valgus reduces the amount of available extension at the 1st MTP joint. 1st MTP extension is essential for normal push off during running, and if it is not available, the body will steal motion from somewhere else (such as the increased knee frontal plane motion and increased foot pronation seen in the Stoneham study). While the results from the Stoneham paper are from barefoot runners, the results could logically be applied to shod runners as well. If a runner has hallux valgus, they will steal motion from another joint, regardless of whether they are barefoot or shod. A shod runner may be more likely to compensate at the knee, particularly if a shoe has a high amount of toe spring that exceeds that person’s available 1st MTP extension range of motion. The simplest thing a runner can do to reduce their risk of developing hallux valgus is to ensure they are wearing shoes (both running and casual) that are wide enough for their forefoot.

Ray, J. J., Friedmann, A. J., Hanselman, A. E., Vaida, J., Dayton, P. D., Hatch, D. J., Smith, B., & Santrock, R. D. (2019). Hallux Valgus. Foot & Ankle Orthopaedics. 

Stoneham, R., Gillian, B., Saxby, L., & Wilkinson, M. The influence of great toe valgus on pronation and frontal plane knee motion during running. The Foot and Ankle Online Journal. 2020; 13(1):7 doi:10.3827/faoj.2020.1301.0007. 

Nakagawa TH, Moriya ÉT, Maciel CD, Serrão AF. Frontal plane biomechanics in males and females with and without patellofemoral pain. Med Sci Sports Exerc. 2012;44(9):1747-1755. doi:10.1249/MSS.0b013e318256903a 

Dierks TA, Manal KT, Hamill J, Davis IS. Proximal and distal influences on hip and knee kinematics in runners with patellofemoral pain during a prolonged run. J Orthop Sports Phys Ther. 2008;38(8):448-456. doi:10.2519/jospt.2008.2490 

Cheung RT, Ng GY, Chen BF. Association of footwear with patellofemoral pain syndrome in runners. Sports Med. 2006;36(3):199-205. doi:10.2165/00007256-200636030-00002


David: I have always enjoyed the Karhu Ikoni as a training shoe. The ride has always been consistent and reliable, though not always the most fun. In todays market the shoe does seem to underperform with some comparisons in responsiveness. I think the improved lockdown and midsole are in the right direction, but I would like to see just a tad more responsiveness out of the Ikoni in the future. Perhaps this could be done utilizing another updated midsole or a spooned out fulcrum and slightly higher drop to give some plate characteristics without changing the shoe too much. Overall though, for logging daily mileage it is still a really nice shoe. 

Andrea: The biggest area of improvement for me would be the foam. The firm midsole kept me from testing this shoe on runs longer than an hour. It would be an incredible long run shoe if the foam was softer. Otherwise, the fit of the Ikoni is near perfect for me and I hope that Karhu will maintain the same spacious toe box and secure heel for future versions of the shoe.


David: The Karhu Ikoni is a "stable neutral" daily training shoe for those that want a grounded ride and a slightly rockered ride. The shoe leans on the firmer end but provides plenty of protection for daily training. Those that have mild stability needs may also have some appeal with the Ikoni as the fulcrum does help with providing some guidance through the rearfoot and midfoot without being overly involved through the forefoot. The foam itself is not life-changing, but the ride the shoe gives is consistent and smooth with each mile. It is a little bit of a "boring" shoe midsole wise, but it honestly rides really nicely and is worth a look if you don't mind not having a newer generation feeling shoe. 

Andrea: The Karhu Ikoni is a neutral daily trainer that is best at easier paces. Those who shy away from 8+mm drop shoes may want to give the Ikoni a try, because the rocker sole makes this shoe perform like a lower drop shoe. Runners who prefer a softer midsole may find the Ikoni too harsh, but those who prefer more responsive cushioning may find a winner here.


"Karhu Ikoni is a neutral daily trainer that serves as a great option for short, easy runs with it’s subtle stability features, cushioning, and mild responsiveness. The mesh upper is lightweight, adaptable, and well-ventilated with a padded and gusseted tongue that further increases the comfort by contouring to the foot. The midsole is made up of Karhu’s new AeroFoam which is a softer foam that what was used in previous models. The midsole includes a half-length midfoot rocker, called the Fulcrum, which is not only responsive but it also offers a level of guidance from the rearfoot to the midfoot. The responsiveness of the midfoot fulcrum is very subtle, however is enough to provide a minor push to propel you forward. The outsole offers decent traction and has only just began to show some wear after ~85 miles of testing. Upon putting these shoes on for the first time, I was impressed with the comfort and fit of the shoe. The upper allows for adequate movement of the foot and increased width in the forefoot, while the midfoot provides a firm lockdown. The gusseted tongue adds to the comfort making the upper feel sock-like in nature. On my first run, the ride was a lot stiffer and more firm than I anticipated and I did not notice the rocker. However, after a few runs (~15 miles or so) to break in the shoe, the ride felt more cushioned and the mild responsiveness from the rocker began to emerge. At this point, the Karhu Ikoni’s began to grow on me and I started using them more regularly on shorter, easy runs up to 70 minutes at most. While I did use them for strides at the end of my easier runs, I would not recommend them for any type of speed or tempo work as the responsiveness is very minimal and not conducive to trying to go fast. I would recommend these shoes to a runner looking for a trainer to transition from a stability shoe to a neutral shoe, because the midfoot Fulcrum and firm cushioning offer mild stability without the use of posting or dual-density foam. One thing that I would change about this shoe going forward is to do away with the “X” cutout in the outsole. As someone who runs on roads and gravel paths, I had a few instances in which a rock or pebble got stuck and I had to stop on a run to remove it. Another recommendation for future models is to improve the responsiveness and cushioning of the shoe which would make it more of a possible option for longer runs." - Contributor Megan Flynn  


Fit: (Great job on upper comfort and lockdown throughout the shoe, even in HiVo option I could still lock this shoe down and length and dimensions were still very good)
Performance: B-
 (Take this with a grain of salt. The ride is really smooth and consistent. The transitions throughout are balanced and nice, though the shoe just isn't very lively. It gets the job done in every category but doesn't feel life changing under foot in any way.)
Stability: A (Great stability integration throughout. The fulcrum is integrated very well and gives a guidance feel, the wide base and sole flaring feel good underfoot, the ground feel is good, and the upper lockdown is good.)
DPT/Footwear Science: B (Great job on stability elements and upper lockdown, now I think the company just needs to take some strides with midsole innovation as the shoe does feel a little unlively especially when running fast. But the ride is still balanced and the shoe has some appeal.)
Personal: B (A shoe for my easy days. I consistent and trustworthy ride that does lack some pizzazz. Gently rockered sole with good stability and moderately flexible forefoot.)
Overall: B+ (A "stable neutral" training shoe with a great upper and great stability elements, though lacks a lively and responsive midsole. Ride throughout is smooth with gently rockered design and moderately flexible forefoot.)

Fit: A (One of the best fitting shoes I’ve tested: wide forefoot, secure heel, comfortable upper)
Performance: A-
(Great for easy miles, but too stiff and firm for intervals)
Stability: B+ (A neutral shoe that is dynamically stable)
DPT/Footwear Science: A (Wide toe box allows for toe splay, which could reduce risk of plantar fasciitis and patellofemoral pain)
Personal: A- (Great fit and a comfortable shoe for easy miles. Improvement could come from softer foam.)
Overall: A- (Great fitting shoe with smooth transitions and a midsole that improves with every run)


Price: $140

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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.

Date of Review: 3/27/2022

***Disclaimer: These shoes were provided free of charge in exchange for a review.  We thank the  people at Karhu 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 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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