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Adidas Adizero Adios 6 Review
By Matthew Klein - Chief Editor & Founder

The Adidas Adizero Adios is a racing shoe with a long history of elite distance running performance. Worn on the feet of many athletes breaking records, repeatedly for the marathon, it has changed greatly since the original Adiprene versions. Five different Boost versions later, the Adios 6 arrives as a complete overhaul of this series. With further expansion of the Adizero line, the Adios 6 (which should really be the Adios 8) now fits in a different position, although long time fans and newcomers will still have things to love. 

Specifications (per Running Warehouse)
Weight: Men's size 9: 8.6 oz / 244 g, Women's size 8: 7.8 oz / 221 g
Stack Height: 32 mm / 24 mm
Drop: 8 mm
Classification: Lightweight Trainer


The Adidas Adizero Adios 6 returns fully redone and redefined. Although billed as a 5k/10k racer, the Adios 6 is more of a lightweight trainer with a more traditional ride on top of a new age twists. A full length Lightstrike midsole fits together with a forefoot Lightstrike Pro and an extended forefoot torsion system make for a snappy ride that works well at tempo runs and intervals. The snug fitting upper feels more like a traditional racing shoe. Yet plenty of firmer cushioning provides protection for more miles for those used to that kind of ride. A great transitional shoe for workouts and uptempo runs, the Adidas Adizero Adios 6 is for those looking for a lightweight trainer with a snug fit.


The Adidas Adizero Adios 6 fits me true to size in my normal men's size 10 men. The width is fairly narrow throughout. This fit is reminiscent of the original unboosted Adios 2, although with a secure fit without the extremely aggressive heel counter and a far lighter upper. The heel through the forefoot is snug with an open mesh that provides decent durability. The forefoot does taper, but the mesh stretches. The open mesh is thin enough to see through and breathes extremely well. The heel has more material around it, with a solid amount of cushioning around the heel collar for a lightweight trainer. The heel collar is somewhat flexible and less aggressive than previous versions. However those that are sensitive to these should be slightly cautious. There is an Achilles notch, which has not caused any chaffing. I have worn the Adios 6 sockless extensively and have had no issues with the heel. I have had some chaffing up at the front due to the large overlays. These have not been bad, but for those sensitive to this, they should be cautious. The tongue is gusseted and somewhat thin. It stays in place and sits nicely against the foot. The upper is snug and performance oriented, so those looking for a well-designed but traditional racing fit will enjoy this upper. 


The ride of the Adios 6 is on the firmer side. The Lightstrike in the heel is firm and bland, but transitions into the Lightstrike Pro in the forefoot. The Lightstrike Pro is more responsive and combined with the snappy flexibility makes for a smooth toe off at fast and slow speeds. There is not a plate, but the more traditional extended forefoot torsion system seen in previous Adios. The softer Lightstrike Pro allows for a high level of flexibility in the front while still allowing for responsiveness up front. The extended forefoot torsion system still allows for flexibility up front, but snaps back nicely during toe off. There is an 8mm heel drop listed, which feels accurate. While there is a small heel bevel, the heel is clunky at slower speeds. At faster speeds, the transition is a bit better, but the Lightstrike in the rearfoot just isn't super exciting. Getting up onto your toes however feels great, with excellent ground feel and responsiveness. 

For being a "racing flat" there is plenty of protection for use as a lightweight daily trainer. For those used to this type of ride, daily training in the Adios 6 is doable. For those not used to a firmer ride, the Adios 6 makes for an excellent tempo/interval shoe. Although not light enough to be considered a true racing flat, the Adios 6 is not as aggressive as others on the market (Adios Pro 1/2, Vaporfly, Endorphin Pro, etc). It is great for multiple uses, particularly when you want a lighter shoe that still has decent ground feel and forefoot flexibility. The Adios 6 rides like a far lighter shoe during intervals and tempo runs, reminiscent of more traditional lightweight trainers. Race distance wise this will be a 10k to half marathon shoe for most people given the firmer cushioning and closer to the ground ride than other new age marathon racers. Those used to lightweight trainers will easily be able to take this up to the marathon, although I still think there are better options for that distance.

The traction on the Adios 6 is good, with a ribbed outsole that grips a variety of smoother surfaces. I would not suggest this shoe for trail running outside of well groomed and non-aggressive trails. The durability is good, with no noticeable wear after 36 miles. So like previous adios shoes, expect a large number of miles.


Despite the narrow midfoot, the Adidas Adios 6 still has some decent mild stability. The extended forked forefoot torsion system provides gentle centered guidance in the forefoot in addition to the snappy feel. The torsion system in the midfoot provides nice rigidity that seems to mildly resist lateral motion. The heel is a bit clunky, but the torsion system and mild lateral heel bevel create a stable rearfoot along with the heel counter. Like the unboosted Adios 2, the ride is naturally stable thanks to the firmer ride, but the torsion system also adds to it. So for those with neutral to mild stability needs, the Adios 6 will do well for you. 


I have always loved Adidas's extended torsion systems. Specifically the ones that go from the heel all the way into the forefoot with the duel forked extension. The midfoot only versions, whether torsion or trusstic, have not worked for me as I feel my feet are missing something working with them in the front half. Enhancing the structures already present in the human body is one of the keys to performance. The extended system acts very much like the plantar fascia. The plantar fascia is a thick band of tissue that extends from the calcaneus (heel bone) all the way to the phalanges (toes) (Bolga & Malone, 2004). It functions to transfer forces from the rear/midfoot to the forefoot, most during the second half of stance phase, ie when your foot is on the ground (McDonald et al., 2016). It has been found to have a similar function regardless of foot strike, although those who land farther forward may put more stress on the overall tissue (Chen et al., 2019; McDonald et al., 2016). However, clinical experience makes me suspect that heel and forefoot strikers simply stress different parts more during initial contact. However, more evidence is needed before I make that conclusion.

The interesting part about the plantar fascia is that it is not a rigid structure. It is an extensible structure that moves, stretches and shortens (Welte et al., 2021).  It does so in response to other mechanisms like the calf, posterior tibias, etc. It cannot keep the foot too rigid as the initial contact and early mid stance require foot flexibility (with control) for shock absorption. The real function occurs as the body transitions over the foot. The plantar fascia tenses up as the calves engage, helping stabilize the foot along with many other ligaments, boney structures, the posterior tibialis, etc. It helps along with all these structures keep the foot rigid as it moves into supination and plantar flexion during the mid stance to toe off or push off phase of gait (Bolgla & Malone, 2004; McDonald et al., 2016; Welte et al., 2021). Additionally, it helps transfer the forces from the calf and plantar flexor muscles driving the foot into plantar flexion into the toes, facilitating the forefoot rocker, ie the transition over the toes. It does not restrict toe motion, but helps transition force through them. The key here is that this structure provides an optimal amount of stiffness/stability/force transmission at the right time. There still needs to be flexibility and power generation in the correct places for this to work.

Hence why I like these extended forefoot torsion systems. They help create a snappy ride that transfers force nicely without being too stiff or limiting motion. The forefoot can still flex/bend, so those who want motion there will still be able to use it without losing responsiveness. Some people will like this, while others will want more or less flexibility. Each person is different, just as each foot and plantar fascia are different. So make sure you figure out what works for you and what you like.

- Matthew Klein PT DPT OCS FAAOMPT


Bolgla, L. A., & Malone, T. R. (2004). Plantar fasciitis and the windlass mechanism: a biomechanical link to clinical practice. 
Journal of athletic training39(1), 77.

Chen, T. L. W., Wong, D. W. C., Wang, Y., Lin, J., & Zhang, M. (2019). Foot arch deformation and plantar fascia loading during running with rearfoot strike and forefoot strike: a dynamic finite element analysis. 
Journal of biomechanics83, 260-272.

McDonald, K. A., Stearne, S. M., Alderson, J. A., North, I., Pires, N. J., & Rubenson, J. (2016). The role of arch compression and metatarsophalangeal joint dynamics in modulating plantar fascia strain in running. 
PloS one11(4), e0152602.

Welte, L., Kelly, L. A., Kessler, S. E., Lieberman, D. E., D'Andrea, S. E., Lichtwark, G. A., & Rainbow, M. J. (2021). The extensibility of the plantar fascia influences the windlass mechanism during human running. 
Proceedings of the Royal Society B288(1943), 20202095.


Although this would certain drive up the cost, I would love to see a full Lightstrike Pro version of the Adios 6. I think (although am not sure as I am not a material science expert) that would keep the weight down, while make the entire ride more responsive. The forefoot is excellent, but the heel is clunky and uninspiring. The upper is very reminiscent of prior Adios, so while it runs a bit narrow, I like it. It does stretch over time and those looking for a snug/narrow fit will enjoy this. I would suggest however opening up the toebox just a bit to reduce some pressure on the toes. While the lightweight trainer function of the Adios will work, I would like to see the weight drop to low 7 ounces to be the 5k/10k racer Adidas has billed this shoe as. 


The Adidas Adizero Adios 6 is a snug/narrow lightweight trainer for those who want a lighter shoe with a more traditional fit or those who want a more traditional racing flat. A bit heavy at 8.6 oz (men's size 9), the Adios 6 will work as a less aggressive, but still fast and snappy shoe for tempo runs, intervals and races from 10k to half marathon. The upper is breathable with a snug/narrow fit throughout. The ride is a bit clunky in the heel, but transitions into a smooth and snappy forefoot. The Lightstrike Pro in the forefoot makes getting onto your toes great, thus despite the weight, the Adios 6 works very well for fast workouts. For those who want a more traditional racing shoe/lightweight trainer, the Adios 6 is a departure from previous Adios, but also a better one at that. 


Fit: B (Secure, narrow/snug fit. A bit cramped in the toes but the upper does stretch)
B (Heavy for a racing flat, but enough cushioning for decent miles and comes alive at faster paces)
Stability: B+ (Torsion system creates mild stability throughout, with heel bevel creating slight lateral bias at heel. )
DPT/Footwear Science: B+ (
Extended torsion system works very well to balance flexibility and responsiveness. Heel bevel could be a little larger/longer to smooth out rear section)
Personal: B (
A good lightweight trainer, although a bit narrow for me. Not up to par in terms of weight for its intended purpose, but works well as a shoe with more ground feel compared to other racing shoes on the market. )
Overall: B (
A narrow/snug fitting, traditional lightweight trainer/ racing flat with a snappy forefoot. Best as a "workout trainer" for those who don't want to run in plated shoes all the time or want a shoe reminiscent of rides from the past. The Lightstrike Pro in the forefoot is very responsive and comes alive when the pace starts to increase, so don't forget to try some fast stuff in this shoe even if it fits more in a lightweight trainer category)


Matt taps into his experience in the entire Adizero line!


Interested in purchasing a pair of the Adidas Adios 6? Visit Running Warehouse here to buy a pair. Using the link to purchase helps support Doctors of Running. Thanks so much!!!

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Doctor of Physical Therapy
Board Certified Orthopedic Clinical Specialist
Fellow of the American Academy of Orthopedic Manual Physical Therapists

Dr. Matthew Klein is a 150 lb male with notable PRs of 14:45 for 5k and 2:32:44 for the full marathon.  He typically runs 70-100 miles per week and trains at a variety of paces from 8min per mile recovery runs to 4:40 per mile 1k repeats.  He prefers firmer and responsive shoes with snug heels and medium to wide toe boxes.  The stability guy of the group, he also prefers a little stability in his footwear. However, as a researcher, clinician and running shoe aficionado, he will run in anything. 

David Salas PT DPT CSCS
Doctor of Physical Therapy
Certified Strength and Conditioning Specialist

Dr. David Salas is a 135 lb male with notable PRs ranging from 3:54 in the 1500m to 1:08:36 for half marathon. He typically runs 60 to 70 miles per week and trains from about 7:30 recovery runs to fast shorter efforts at 4:30 pace. He normally prefers neutral shoes with a firmer ride, but is completely open to other types of shoes.  He is a footwear enthusiast at heart and will always appreciate a high quality shoe when it comes around. For updates on training or testing, 

Nathan Brown PT DPT MS
Doctor of Physical Therapy 
Masters in Anatomy and Clinical Health Science
Movement Performance Institute Certified in Advanced Functional Biomechanics 

Dr. Brown is a 155 lb male with notable PRs of 18:18 5K, 39:25 10K, 1:29:01 half marathon, and 3:54 marathon. He typically runs between 20-40 miles per week at a variety of paces from 7:30-8:30 min/mile for recovery runs to 6-6:45 min/mile for tempo runs. He typically prefers shoes that provide some cushioning underfoot but still maintain a more firm and responsive feel. Current goals for 2020 are to break the 1.5 hour half marathon and 3:30 marathon.

Bach Pham MS
Marketing and Social Media Manager
Master of Arts in Cultural Anthropology

Bach Pham is a 140 lb male with PRs of 23 5K, 52 10K. He typically runs between 25-35 miles per week at a variety of paces between 8:30 (tempo) -10:00 (recovery) min/miles. He typically prefers shoes that provide some mild to firm cushioning underfoot that is lightweight and responsive. Currently his goals are to complete the half and marathon distances.

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 Adidas Running and Running Warehouse 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.

Please feel free to reach out, comment and ask questions!
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