adidas Ultraboost 21

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adidas Ultraboost 21: Review

“A cushioned and stylish running shoe for daily training.”

Overview


The adidas Ultraboost 21 is a running shoe designed to provide a blend of comfort and performance. This shoe is known for its advanced cushioning and stylish design, making it a popular choice among runners and casual wearers alike.

Key Features:

  • Boost Midsole: Enhanced cushioning with 6% more Boost foam for a responsive ride.
  • Primeknit+ Upper: A seamless, stretchy upper that offers a sock-like fit and improved comfort.
  • LEP System: Linear Energy Push system (increases forefoot stiffness for better energy return) for increased forefoot stiffness and better energy return.
  • Crystal Rubber Outsole: Durable outsole with excellent grip and smooth ride transitions.

The adidas Ultraboost 21 is an ideal choice for runners who prioritize cushioning and comfort for daily running. Its advanced midsole technology offers a responsive ride, making it suitable for long-distance runs.

With an average review score of 74%, it's in the lowest rated 20% of similar running shoes. Based on our monitoring of prices across the internet, it's currently just above the median price of running shoes today.

Verdict

The consensus on the adidas Ultraboost 21


The adidas Ultraboost 21 has received mixed reviews from experts. While it offers a smooth ride and durable construction, its increased weight and firm cushioning have been points of contention. The shoe's Boost midsole provides a cushioned yet firm ride, suitable for easy and recovery runs. However, the loose heel and relaxed upper limit its performance to straight-line running at slower paces. The Primeknit+ upper offers a comfortable, sock-like fit, but breathability is limited. The LEP system adds stability and structure, but some runners find it too stiff. Overall, the Ultraboost 21 is a well-built shoe with excellent durability, but its heavy weight and firm ride may not appeal to all runners. It is best suited for casual runners looking for a stylish, cushioned shoe for easy runs.

Updates to adidas Ultraboost 21


The adidas Ultraboost 21 has several major updates compared to previous models in the adidas Ultraboost family. It features 6% more Boost foam in the midsole, providing enhanced cushioning and energy return. The new LEP system increases forefoot stiffness for better propulsion. The Primeknit+ upper offers a more comfortable, sock-like fit. The crystal rubber outsole design improves durability and ride transitions. These updates make the Ultraboost 21 a more stable and cushioned option for daily running.

Comparable Shoes


The Nike ZoomX Invincible Run is a good alternative to the adidas Ultraboost 21 for runners seeking a lighter and more flexible shoe. The Invincible Run features a springier and softer midsole, making it suitable for faster paces. While the Ultraboost 21 offers better stability and durability, the Invincible Run excels in responsiveness and comfort for speed training.

The Saucony Triumph 18 is another cushioned running shoe comparable to the adidas Ultraboost 21. The Triumph 18 has a slightly lighter weight and a more flexible midsole, providing a smoother ride. Both shoes offer excellent cushioning and support, but the Triumph 18 may be a better option for runners seeking a more versatile and responsive shoe for various paces.

The adidas Solar Boost 3 is a more affordable alternative to the Ultraboost 21. It features a similar Boost midsole but with less cushioning, making it lighter and more versatile. The Solar Boost 3 offers good impact protection and a smooth ride, making it suitable for daily running. Runners seeking a durable and comfortable shoe at a lower price point may prefer the Solar Boost 3.



The Reebok Floatride Energy 3 is a versatile and lightweight running shoe that compares well with the adidas Ultraboost 21. It features a cushioned midsole made of a similar material to Boost, providing good energy return and comfort. The Floatride Energy 3 is lighter and more responsive, making it suitable for a wider range of paces. Runners looking for a versatile and affordable shoe may find the Floatride Energy 3 a better option.



The adidas Boston 9 is a performance-oriented running shoe that offers a more responsive and lightweight alternative to the Ultraboost 21. It features a thicker stack and a firmer midsole, making it suitable for speed training and racing. While the Ultraboost 21 excels in cushioning and comfort, the Boston 9 is ideal for runners seeking a faster and more agile shoe for various paces.

Special versions of adidas Ultraboost 21




The adidas Ultraboost 21 GTX is a special version designed for wet and cold conditions. It features a waterproof Gore-Tex upper, providing protection against rain and snow. The GTX version retains the Boost midsole and LEP system for cushioning and stability. This model is ideal for runners who need a durable, weather-resistant shoe for daily running in challenging conditions.



The adidas Ultraboost 21 Primeblue is an eco-friendly version made with recycled materials. The Primeblue upper is constructed from Parley Ocean Plastic, highlighting adidas's commitment to sustainability. This version maintains the Boost midsole and LEP system for cushioning and stability. The Primeblue model is suitable for environmentally conscious runners seeking a cushioned and supportive shoe for daily running.

10 adidas Ultraboost 21 Pros & Cons


5 Pros

Smooth ride transitions
Durable construction
Comfortable, sock-like fit
Excellent cushioning and support
Good grip on various surfaces

5 Cons

Heavy weight
Firm midsole
Limited breathability
Loose heel lockdown
Expensive price

In Depth


Upper

The adidas Ultraboost 21 features a Primeknit+ upper, which provides a seamless, sock-like fit. This stretchy material conforms to the foot, offering excellent comfort and support. However, the breathability of the upper is limited, making it less suitable for hot weather. The plastic midfoot cage adds stability but can create pressure points over longer runs. Overall, the upper is comfortable and supportive, but some runners may find it too warm for extended use.

Midsole

The Boost midsole in the adidas Ultraboost 21 is designed to offer a cushioned and responsive ride. With 6% more Boost foam than previous versions, it provides excellent energy return and comfort. However, the midsole is firmer than expected, which may not appeal to runners looking for a plush ride. The Linear Energy Push (LEP) system adds stability and structure, making the shoe suitable for easy and recovery runs. Despite its benefits, the midsole's firmness and weight may limit its versatility.

Outsole

The outsole of the adidas Ultraboost 21 features crystal rubber, which offers excellent durability and grip. The new design provides smoother ride transitions and better stability. The crystal rubber is firmer than previous versions, contributing to the overall stiffness of the shoe. While the outsole performs well on various surfaces, its firmness may not be ideal for runners seeking a softer ride. Overall, the outsole is durable and provides good traction, making it suitable for long-distance runs.

Size/fit

The adidas Ultraboost 21 fits true to size, with a medium toe box that accommodates most foot shapes. The Primeknit+ upper offers a snug, sock-like fit, but the loose heel can cause some slippage during runs. The plastic midfoot cage provides good lockdown, but the overall fit may feel too relaxed for runners seeking a more secure fit. Despite these issues, the shoe's stretchy upper and true-to-size fit make it comfortable for daily running.

Comfort

Comfort is a standout feature of the adidas Ultraboost 21. The Primeknit+ upper provides a soft, sock-like fit, while the Boost midsole offers cushioned support. However, the shoe's firmness and weight may detract from its overall comfort, especially during longer runs. The LEP system adds stability, but some runners may find it too stiff. Despite these drawbacks, the Ultraboost 21 remains a comfortable option for easy and recovery runs.

Cushioning

The Boost midsole in the adidas Ultraboost 21 offers a cushioned yet firm ride. With 6% more Boost foam, it provides excellent energy return and support. However, the midsole is firmer than previous versions, which may not appeal to runners seeking a plush ride. The cushioning is suitable for easy and recovery runs, but the shoe's weight and firmness may limit its versatility. Overall, the Ultraboost 21 provides good cushioning for daily running.

Breathability

Breathability is a concern with the adidas Ultraboost 21. The Primeknit+ upper, while comfortable and stretchy, does not offer adequate ventilation for hot weather. Runners may find their feet getting warm during extended runs. Despite this, the upper's seamless design provides a snug, sock-like fit that is comfortable for daily running. For those prioritizing breathability, other models may be more suitable.

Stability

Stability is a key feature of the adidas Ultraboost 21. The LEP system and wide midsole base provide excellent support and structure. The plastic midfoot cage adds to the shoe's stability, making it suitable for easy and recovery runs. However, the shoe's firmness and weight may limit its performance for faster paces. Overall, the Ultraboost 21 offers good stability for runners seeking a supportive, cushioned shoe.

Durability

The adidas Ultraboost 21 is built to last, with a durable crystal rubber outsole and a robust Primeknit+ upper. The Boost midsole retains its cushioning properties over time, making the shoe suitable for long-distance running. The plastic midfoot cage and LEP system add to the shoe's overall durability. Despite its weight, the Ultraboost 21 is a reliable option for runners seeking a long-lasting, cushioned shoe.

Grip

The crystal rubber outsole of the adidas Ultraboost 21 provides excellent grip on various surfaces. The new design offers smoother ride transitions and better traction. The firm rubber contributes to the shoe's overall stability, making it suitable for long-distance runs. While the grip is reliable, the outsole's firmness may not appeal to runners seeking a softer ride. Overall, the Ultraboost 21 offers good traction and stability for daily running.

Flex

Flexibility is limited in the adidas Ultraboost 21 due to its firm midsole and LEP system. The shoe's design prioritizes stability and support over flexibility, making it suitable for easy and recovery runs. The Primeknit+ upper offers some stretch, but the overall stiffness of the shoe may not appeal to runners seeking a more flexible ride. Despite this, the Ultraboost 21 provides a stable and supportive option for daily running.

Who should buy the adidas Ultraboost 21?


Runners who prioritize comfort and cushioning for daily running will find value in the adidas Ultraboost 21. Its Boost midsole offers a responsive ride, while the Primeknit+ upper provides a snug, sock-like fit. The shoe is suitable for easy and recovery runs, making it ideal for casual runners. Those who appreciate a stylish design and durable construction will also benefit from this model.

Who should not buy the adidas Ultraboost 21?


Runners seeking a lightweight, flexible shoe for faster paces may not find the adidas Ultraboost 21 suitable. Its heavy weight and firm midsole limit its versatility for speed training. Those who need a highly breathable shoe for hot weather may also want to consider other options. If stability and a secure fit are top priorities, other models with better heel lockdown may be more appropriate.

adidas Ultraboost 21: What's it good for?


The adidas Ultraboost 21 is good for daily running and everyday training. Its cushioned Boost midsole makes it suitable for road running and long-distance runs. The shoe's stability and support are ideal for easy and recovery runs. Casual runners who appreciate a stylish design will also find this model appealing.

8 adidas Ultraboost 21 FAQs


Is the adidas Ultraboost 21 suitable for daily running?

Yes, the adidas Ultraboost 21 is designed for daily running. Its Boost midsole provides excellent cushioning and energy return, making it suitable for easy and recovery runs. The Primeknit+ upper offers a comfortable, sock-like fit, enhancing overall comfort during daily training.

How does the adidas Ultraboost 21 compare to previous models?

The adidas Ultraboost 21 features several updates compared to previous models. It has 6% more Boost foam in the midsole, providing enhanced cushioning and energy return. The new LEP system increases forefoot stiffness for better propulsion. The Primeknit+ upper offers a more comfortable, sock-like fit, and the crystal rubber outsole design improves durability and ride transitions.

Is the adidas Ultraboost 21 suitable for long-distance running?

Yes, the adidas Ultraboost 21 is suitable for long-distance running. Its Boost midsole provides excellent cushioning and support, making it comfortable for extended runs. The shoe's stability and durability also make it a reliable option for long-distance training.

Is the adidas Ultraboost 21 breathable?

The Primeknit+ upper of the adidas Ultraboost 21 offers a snug, sock-like fit, but its breathability is limited. Runners may find their feet getting warm during extended runs, especially in hot weather. For those prioritizing breathability, other models may be more suitable.

What is the weight of the adidas Ultraboost 21?

The adidas Ultraboost 21 weighs 340 g (12 oz) for men and 312 g (11 oz) for women. Its weight is on the heavier side, which may limit its versatility for faster paces. However, the shoe's cushioning and stability make it suitable for easy and recovery runs.

Is the adidas Ultraboost 21 suitable for heel strikers?

Yes, the adidas Ultraboost 21 is suitable for heel strikers. The shoe features a 10 mm heel-to-toe drop and a cushioned Boost midsole, providing good impact protection and support for heel strikers. The LEP system and wide midsole base add stability, making it a reliable option for runners with a heel strike pattern.

Does the adidas Ultraboost 21 have a removable insole?

Yes, the adidas Ultraboost 21 has a removable insole. This feature allows runners to use custom orthotics or replace the insole for added comfort and support. The removable insole adds to the shoe's versatility and customization options.

Is the adidas Ultraboost 21 suitable for runners with high arches?

Yes, the adidas Ultraboost 21 is suitable for runners with high arches. The shoe's Boost midsole provides excellent cushioning and support, while the Primeknit+ upper offers a snug, sock-like fit. The LEP system adds stability, making it a reliable option for runners with high arches.

adidas Ultraboost 21 alternatives



adidas Ultraboost 21
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adidas Ultraboost 21
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productAthletes
Pro athlete users

Annie Rodenfels
Weight
Weight
M: 340 g
W: 312 g
M: 283 g
W: 264 g
M: 278 g
W: 249 g
M: 286 g
W: 224 g
M: 303 g
W: 261 g
Forefoot
Forefoot
21 mm
28 mm
28 mm
29 mm
34 mm
Heel to toe drop
Heel to toe drop
10 mm
10 mm
10 mm
10 mm
8 mm
Heel
Heel
31 mm
38 mm
38 mm
39 mm
42 mm
Brand
Brand
adidas
BrooksBrooksBrooksPUMAASICS
Strike Type
Strike Type
Heel strike
Heel strikeHeel strikeHeel strikeFore/Midfoot strikeHeel strikeFore/Midfoot strikeHeel strike
Shoe Type
Shoe Type
ComfortableComfortableMaximalistComfortableMaximalistComfortableMaximalistComfortableMaximalist
Rocker
Rocker
Techs
Techs
adidas Ultraboost
Brooks BioMoGo DNA
PUMA NITROASICS GelOrthoLite
Environmental Characteristics
Environmental Characteristics
SustainableVegan ⓋSustainableVegan Ⓥ
0

adidas Ultraboost 21: what the experts say (3 reviews)

adidas Ultraboost 21: 20 Expert video reviews

adidas Ultraboost 21 characteristics and specifications

Characteristics
SportsRunning (+2002)
TerrainRoad (+1326)
UsagesDaily running (+1102)
Brandadidas (+287)
Support TypeNeutral (+1563)
Pronation TypeNeutral pronation (+1543)
Strike TypeHeel strike (+1067)
Arch TypeHigh arch (+1490)
FitMedium toe box (+826)
FeaturesOrthotic friendly (+419)Removable insole (+402)
MaterialsKnit (+204)
Techsadidas Ultraboost (+41)
ColorwaysAmbient Blush / Ambient Blush / Halo Blush, Ash Pearl / Ash Pearl / Hazy Rose, Ash Pearl / Cloud White / Halo Ivory, Black / Beige Tone / Signal Green, Black / Black / Core White, Black / Black / Grey Five, Black / Black / Violet Tone, Black / Cloud White / Violet Tone, Black / Copper, Black / Focus Olive / Acid Yellow
Specificationsvs Average
Model
21
Released
Jan 2021
Measurements
Weight
M: 340 g
W: 312 g
Heel to toe drop
10 mm
Heel
31 mm
Forefoot
21 mm

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AuthorTom Green
Tom is the founder of geerly. Based in West London, he found his passion for running in his mid-30s. He’s best at longer distances, and is a regular at the London Marathon, where he's edging closer to sub-2.40. He started geerly because he found it frustrating when shopping for running shoes spending ages trying to find the best deal in his size, and wading through verbose, waffling reviews clearly designed to appeal to search engines rather than be helpful to users. For geerly he's passionate about writing reviews that get straight to the point, and helping runners find the right gear at the best price.
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July 16, 2024 at 9:55 AM
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