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Adidas Ultraboost Light Review: Lighter, but is it Runnable?
By Chief Editor Matthew Klein

For the longest time, the Adidas Ultraboost series is a highly cushioned, comfortable casual shoe that attempted to be a running shoe. Although it featured many components that normally would do well for this sport, including a high level of cushioning, a secure upper and other features (including the recent addition of an excellent split heel counter), the weight of this line kept it from truly being a solid running shoe. Sitting at over 11.5 to 12 oz for men's size 9, this was a tank of a shoe that worked far better for walking and casual use than for higher-speed activities. The Ultraboost Light attempts to bring the weight down to a more manageable level and finally make this a running shoe. While still not a light shoe by any means, the latest edition of the Ultraboost is the first of the series that enters a weight realm and level of function that could be considered a true running shoe.

Adidas Ultraboost Light
Price: $190 at Adidas
Weight: 10.3 oz, 292g (men's size 9), 9.2 oz, 261g (women's size 7)
Stack Height: Not Provided
Drop: 10 mm
Classification: High Cushion Daily Training Shoe


The Adidas Ultraboost Light is the first version of the Ultraboost in awhile that feels like a running shoe. The weight and cushioning is consistent with a daily training shoe, featuring a large amount of new Light Boost that helps drop the weight and a comfortable Primeknit upper. A low-volume, slightly wider fit sits up top with a surprising amount of security for a one-piece upper. The ride underfoot is cushioned in the heel and slightly firmer in the forefoot with an LEP plastic plate that helps facilitate motion forward. The Ultraboost Light is a highly cushioned daily training shoe with a sock-like upper for those who want something for easy miles, long runs and even some casual wear.

: Hoka Bondi 8, New Balance Fresh Foam More v4


The Adidas Ultraboost Light fits me true to size length-wise in my normal men's US size 10. The width is slightly wider, but the volume is quite low, especially in the forefoot. The Primeknit upper is a single unit with a separate midfoot cage for the laces. The forefoot has slightly above normal width but the upper sits extremely low. This causes a compressive fit initially that feels tight, but loosens as the upper breaks in. I initially thought the fit was slightly short for this reason, but with time it felt true to size. There is no tongue as the upper is a single piece and holds snug against the midfoot. I have not had any issues with the upper crumpling, The midfoot cage does secure the foot decently, but there no last eyelet to lace lock. This has been fine at easy paces, but I have had some issues with lateral and superior movement during faster efforts.

The heel features a split external heel counter. This has done extremely well for me as there is no pressure on the posterior aspect of my calcaneus (that can be sensitive). The counter comes up along the medial and lateral aspects of the heel, which centers things without being too aggressive. There is additional padding around the heel collar, so those sensitive to heel counters should do quite well with this shoe. This combined with the sock-like upper creates a decently secure heel side to side. The security as mentioned is decent in the heel and midfoot side to side. When running faster, the sock-like upper tends to move a little more, which does not feel as secure. Those using this shoe for easy runs and long runs will do fine, while those wanting a shoe for uptempo or faster efforts may want to look elsewhere.


The Adidas Ultraboost Light is a daily training shoe with a highly cushioned heel and a firmer forefoot. The midsole is full-length Light Boost, which is a lighter and slightly firmer version of normal Boost. There is a large amount of this in the heel, which provides a softer rearfoot landing. There is less in the midfoot and forefoot, which combined with the plastic LEP (Linear Energy Push) makes for a firmer and snappier ride up front. There is a 10mm drop listed for this shoe and it feels lower than this when landing at the heel. The foam compresses and it feels more like 7-8mm. The heel is large and most of the weight is biased toward the rearfoot. There is a large rounded with a posterior lateral bevel that does make rearfoot landings decent. The transition forward off the heel is quite good and the LEP works to progress you forward nicely. The forefoot is firmer and snappy when rolling through, but feels slappy and awkward when trying to land there initially. This is a shoe that will probably work better for rearfoot strikers unless you want a firmer place to land at the forefoot.

The LEP stiffening agent seems to work better transitioning you through the midfoot/forefoot off the heel than landing directly on top of it. Although the weight has been reduced in the shoe compared to its predecessor by ~2 ounces, it is still far more in the daily trainer category than any other area. Mild pickups feel fine, but attempting anything faster feels awkward in this shoe with the larger heel.

The Adidas Ultraboost Light is best as a comfortable daily training shoe for easy miles and longer efforts. I have attempted a variety of efforts and found this to continue to be the case even as the shoe broke in. It provides plenty of cushioning and protection over longer miles, making it great for daily use. However, it does not have the nimbleness or true lightness to be a speed shoe with others like the Adios 8 and Adios Pro 3 filling that gap much better.

Surface-ise the Ultraboost Light does best on road surfaces and light trail. The thickness of the shoe can handle some trail, but the outsole is really designed for smooth surfaces and should not be used on technical terrain. The traction is dry surfaces is as expected, while wet pavement is decent, but nothing to write home about. I have 60 miles on my pair and have only just begun to see some mild outsole wear in my normal spot (posterior lateral heel). The rest of the outsole looks completely fine and I expect to get an above-average number of miles out of this shoe as a daily trainer. 


The Ultraboost Light is not a stability shoe, but has several features that make it a stable neutral shoe. One of the biggest factors in this is how wide the sole is. There is a large amount of sole flare medially and laterally throughout the length of the shoe. This is offset in the heel with a posterior lateral bevel, but the lateral sole flare begins quickly after that. This provides some resistance to medial and lateral motion. The long external heel counter that travels on the medial and lateral side also works with the large rearfoot sidewalls (which surrounds the heel completely) to provide a centered, stable heel landing. There is a strong guidance line through the length of the shoe that facilitates forward motion. Finally, the LEP spans the width of the shoe in the forefoot and mostly in the midfoot, providing additional rigidity that facilitates forward motion. Finally, the Light Boost, while cushioned, is firmer than the traditional Boost, making it comparatively more stable. The combination of these factors create a solidly stable neutral heel with some mild guidance in the forefoot due to the stiffness and increased midsole firmness up front. 

Thoughts as a DPT: Shoe Mass and Running Economy
By Matthew Klein

While there are plenty of new foams on the market that are challenging our understanding of what improves running economy, weight is still a major factor in the efficiency of a running shoe (Hunter et al., 2019). It is common to hear the reference that for every 100g taken off a shoe or put on it, there is a 1% increase or decrease in running economy (efficiency) (Rodrigo-Carranza et al., 2020). That is true only to a point as lighter shoes with softer and more resilient foams (like many in the super shoes we see today) tend to improve economy more compared to firmer or minimalist shoes without any cushioning (Worobets et al., 2014). The key is that lighter cushioned shoes may improve running efficiency, but take those variables by themselves and your results may vary (on the many other factors that go into this). Regardless, for truly running fast, a lighter weight is needed. The majority of competitive shoes on the market for running fast are all under or at about 8 oz with many going under 7. While they feature a large amount of these newer, resilient foams, it is the combination of this material, the weight, optimal stiffness and geometry that truly make them light and efficient. 

The Adidas Ultraboost Light is certainly a much nimbler Ultraboost. Dropping the weight by ~ 2 oz (~50g ish) will go a long way for a new runner getting used to the demands of running. While the prior two versions were far better than any other previous version, they were still quite heavy. Extremely heavy shoes can put excessive stress on certain areas of the body in addition to reducing running efficiency due to having to carry more weight. The hip flexors (Psoas muscles, tensor fascia latae, iliacus, etc) take the majority of this stress as they have to lift a now highly weight limb forward during the swing phase of running to prepare for landing. Other muscle groups that can be stressed by this include the calf muscles and hamstrings. The calf muscles are the primary propulsive muscles during running, so any additional weight means more required force production for forward momentum. The hamstrings have to deal with increased eccentric forces as they slow the increased weight of the foot/shoe down during the 2nd part of the stance phase of gait for a normal landing. As mentioned above, this does not mean a super light minimalist shoe is best for everyone as an optimal amount of cushioning is still needed depending on the individual's needs, speed, etc. The reduction in weight for this shoe is a great step forward for Adidas as it continues to bring the Ultraboost series into the arena as an actual running shoe. 


Hunter, I., McLeod, A., Valentine, D., Low, T., Ward, J., & Hager, R. (2019). Running economy, mechanics, and marathon racing shoes. Journal of sports sciences37(20), 2367-2373.

Rodrigo-Carranza, V., González-Mohíno, F., Santos-Concejero, J., & González-Ravé, J. M. (2020). Influence of shoe mass on performance and running economy in trained runners. Frontiers in Physiology11, 573660.

Worobets, J., Wannop, J. W., Tomaras, E., & Stefanyshyn, D. (2014). Softer and more resilient running shoe cushioning properties enhance running economy. Footwear Science6(3), 147-153.


I have enjoyed the Ultraboost Light far more than any previous Ultraboost. The relatively lighter weight while maintaining a solid amount of cushioning has made this a decent training shoe. However, there are some suggestions that I have for this model. If they are truly going to call this "Light," I would like to see this under the 10 oz range. 10.3 oz (men's size 9) is still on the heavier for a road daily training shoe in today's world. I would also like to see Adidas find a way to keep the weight more well-adjusted across sizes. My men size 10 leaps into the 11 oz (over 311 g) territory, which is a big difference from the listed weight.

My second suggestion is to shift the source of upper security from the lower volume fit to improve security at the midfoot. The upper is a light knit (Primeknit) that feels great against the foot. While it does stretch somewhat, the lower volume may limit those with higher-volume feet from wearing this. The midfoot cage design is a great way to drop weight, but it may be beneficial to connect that to the upper to better lock things down. 


The Adidas Ultraboost Light is a daily training shoe for those who prefer a softer/larger rearfoot and a firmer forefoot with a low-volume knit upper. The new Ultraboost Light midsole provides a large amount of cushioning in the rear that rolls you forward through a firmer and snappier forefoot. The upper has normal/slightly wider fit that feels on the snug side thanks to a low-volume Primeknit upper that wraps the foot. Coming in as the lightest Ultraboost ever, while this is not a speed day shoe, the decreased weight makes it far easier on the legs while maintaining the progressions made for the previous couple of versions that continue to make this a true running shoe. I am curious where this puts the Solar series now (Solarboost, Solar Control, Solarglide) as the Ultraboost Light is 1-2 oz lighter than any of Adidas's normal running trainers. I hope Adidas takes what they have learned from the Ultraboost Light and adds it to all their normal running trainers. While the racers are doing great, an update to the trainers is necessary to bring them back to a competitive level against other brands.


Fit: B+ (Slightly wider but low volume stretchy upper. Secure heel and midfoot)
B/B+ (Far lighter than previous models. Still a training shoe for easy miles and long runs, albeit a solid one)
Stability: A- [Stable Neutral}] (Wider platform, central groove, wide plastic plate, massive sidewalls and heel cage for an inherently stable shoe, especially in the rearfoot)
DPT/Footwear Science: A-/B+ (Excellent upgrade of the Ultraboost line that actually makes it a running shoe. Solid foam update with stable neutral design that should work well for new runners, especially with the lighter weight)
Personal: B+ (Solid comfortable daily trainer that will make running more accessible for the fashion-conscious public. Could still be a bit lighter to truly hold that name, although it is far lighter than prior Ultraboost)
Overall: B+


Adidas Ultraboost Light
$190 at Adidas

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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 Adidas 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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