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DAILY TRAINING

DAILY TRAINING

DAILY TRAINING

Nike ZoomX Invincible Run

Nike ZoomX Invincible Run
The Invincible Run is a unique shoe which is incredibly versatile with its ultra soft and bouncy ride.
The Invincible Run is a unique shoe which is incredibly versatile with its ultra soft and bouncy ride.
Brandon Law
Marathon Runner and Shoe Expert

DAILY SUPPORT

DAILY SUPPORT

DAILY SUPPORT

Nike React Miler

Nike React Miler
If you are looking for a running shoes to comfortably run long distances - while being cushioned and protected - the Miler is best in class.
If you are looking for a running shoes to comfortably run long distances - while being cushioned and protected - the Miler is best in class.
Sarah Dean
5k Runner, Personal Trainer

TEMPO TRAINING

TEMPO TRAINING

TEMPO TRAINING

Nike Air Zoom Tempo Next%

Nike Air Zoom Tempo Next%
The Tempo Next% offers a similar explosive ride and feel to its more expensive racing counterpart but has a more durable midsole and outsole.
The Tempo Next% offers a similar explosive ride and feel to its more expensive racing counterpart but has a more durable midsole and outsole.
Brandon Law
Marathon Runner and Shoe Expert

BEST VALUE

BEST VALUE

BEST VALUE

Nike Air Zoom Winflo 7

Nike Air Zoom Winflo 7
With looks and tech directly coming from the more expensive shoes in the range, the Winflo is amazing value for under $90.
With looks and tech directly coming from the more expensive shoes in the range, the Winflo is amazing value for under $90.
Sarah Dean
5k Runner, Personal Trainer

RACING

RACING

RACING

Nike Air Zoom Alphafly Next%

Nike Air Zoom Alphafly Next%
Having a full carbon plate, explosive Zoom Air pods and brand new Atomknit, the Alphafly holds the record for the fastest ever marathon distance.
Having a full carbon plate, explosive Zoom Air pods and brand new Atomknit, the Alphafly holds the record for the fastest ever marathon distance.
Brandon Law
Marathon Runner and Shoe Expert

Nike is one of the most innovative running shoe brands out there. While they do stick to some popular models for years (ie the more than 30 years history of the Nike Pegasus), they constantly introduce new technologies and with them, new names and classification.

This article will help you make sense of all those model names, technical jargon and finally understand which of Nike's running shoes is meant for which runner.

Nike Air Zoom Series

The first and most popular category is the "Zoom" family of running shoes. Built around the hyper-popular Pegasus, it includes shoes that are meant for both daily training, speedwork training and even race day.

Zoom Air is is characterised by a fast and responsive ride that still provides great cushioning.

First choice

Nike Pegasus 38

Weight
10.2 oz.
Drop
10 mm.
Category
Cushioning

Nike Pegasus 38

Reasons to buy
  • More accommodating upper with great lockdown
  • High level of cushioning
  • Impressive build quality
  • Great value for money
“The Nike Air Zoom Pegasus 38 is a very well-built daily trainer which is not as versatile as previous Pegasus models but is soft and cushioned enough for long distances.    Version 38 is an upper only update which fixes the narrow fit and heel slippage of the previous version ”
Recommended for
If you don't buy running shoes often and you're looking for a durable trainer that won't break the bank, the Pegasus 38 is the shoe for you.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of Pegasus 38
or buy them here: Men / Women
Also consider

Nike Air Zoom Winflo 7

Weight
10 oz.
Drop
10 mm.
Category
Cushioning

Nike Air Zoom Winflo 7

Reasons to buy
  • Great value
  • AirZoom pods for cushioning and responsiveness
  • Premium design looks great on the foot
“Similar to the Pegasus but with a smaller Zoom unit, the Winflo is a entry level neutral running shoe that is perfect for beginners while they build up their mileage. ”
Recommended for
The Winflo 7 is for neutral runners, looking for a cushioned shoe for the longer run, to be used as a versatile daily trainer.
Aimed at runners looking for a shoe that blends great technology, fantastically sleek, modern looks and a good value price tag.
If you want responsive Zoom foam...
Sarah Dean
5k Runner, Personal Trainer
Read the full review of Air Zoom Winflo 7
or buy them here: Men / Women
Also consider

Nike Air Zoom Tempo Next%

Weight
8.9 oz.
Drop
10 mm.
Category
Cushioning

Nike Air Zoom Tempo Next%

Reasons to buy
  • Comfortable upper with no heel slippage.
  • Explosively responsive forefoot.
  • Durable outsole and midsole foams.
  • Somewhat similar ride to the Alphafly.
“The Nike Tempo Next% is supposed to be the replacement for the Pegasus Turbo 2 and a training companion for the Alphafly Next%.    While having a very unique and highly responsive ride, the Tempo Next% rides much firmer than the Pegasus Turbo 2 and a little too firm for easy and marathon paced runs. It's best suited to fast runs below 15 kilometres. ”
Recommended for
If you're a heavier runner looking for a shoe for mainly fast runs and price isn't an issue, get the Tempo Next%.
It has a comfortable upper with great lockdown and a firm but very responsive ride.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of Air Zoom Tempo Next%
or buy them here: Men / Women
Also consider

Nike Air Zoom Vomero 15

Weight
10.2 oz.
Drop
10 mm.
Category
Cushioning

Nike Air Zoom Vomero 15

Reasons to buy
  • Insanely durable outsole
  • Highly responsive forefoot
  • Plush and comfortable upper
  • Stable ride
“The Nike Air Zoom Vomero 15 is a major update and a vast improvement over the Vomero 14. The plush upper makes its comeback on the Vomero 15 and its ride is noticeably more cushioned than the previous version.   Compared to other max cushioned trainers, the Vomero 15 rides firmer because of its large forefoot Zoom Air unit.”
Recommended for
If you're a runner looking for a daily training alternative to the Pegasus 37 that has a more comfortable upper and a much more durable outsole, the Vomero 15 is a good buy.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of Air Zoom Vomero 15
or buy them here: Men / Women
Also consider

Nike Air Zoom Structure 23

Weight
10.2 oz.
Drop
8 mm.
Category
Cushioning

Nike Air Zoom Structure 23

Reasons to buy
  • Wide base with a stable ride.
  • Soft midsole with deep cushioning.
  • Plush, comfortable upper.
  • Zoom Air bag in the forefoot adds responsiveness
“The Nike Air Zoom Structure 23 shares nothing in common with its predecessor except for its name. It has a brand new plusher upper and midsole with a durable outsole which results in a much softer and less versatile ride.”
Recommended for
If you're a neutral runner or an overpronator looking for a stable, max-cushioned trainer for recovery or long runs, the Structure 23 is the shoe for you.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of Air Zoom Structure 23
or buy them here: Men / Women

Nike React Series

React is the name of one of the new Nike foam materials for shoe midsoles.

Originally introduced in their basketball shoe line, it has made its way (successfully) into the running shoe line.

The main characteristics of the React foam are a unique combination of cushioning (soft while compressible) and responsiveness (the ability to quickly return to its original shape).

Although many brands make similar claims about their latest foams, we tested the Nike React running shoes and we agree that this material is a game changer.

First choice

Nike React Infinity Run 2

Weight
9.9 oz.
Drop
9 mm.
Category
Cushioning

Nike React Infinity Run 2

Reasons to buy
  • Deep, bottomless cushioning
  • Smooth ride transitions
  • Excellent foot lockdown
  • Versatile
“The Nike React Infinity Run Flyknit 2 is a versatile max-cushioned daily trainer which excels at easy-paced daily training and long runs. It has been updated with a new upper which improves foot lockdown and overall performance. ”
Recommended for
If you’re a runner looking for a neutral daily trainer with high levels of cushioning, smooth ride transitions and you don’t mind some arch support, the React Infinity Run Flyknit 2 is the shoe for you.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of React Infinity Run 2
or buy them here: Men / Women
Also consider

Nike Zoom Fly 3

Weight
8.9 oz.
Drop
8 mm.
Category
Lightweight

Nike Zoom Fly 3

Reasons to buy
  • Carbon Fiber Plate Midsole is Responsive and Fast
  • Improved Outsole Durability and Traction from Zoom Fly Flyknit
  • VaporWeave Upper Material
  • Cheaper and More Durable than Higher-End Options
“The Zoom Fly 3 is the “affordable” version of the Nike premium distance racing shoes. While this is the tier below the Vaporfly 4% and Next% shoes, the Zoom Fly 3 come with premium Nike running shoe features in a more accessible format.”
Recommended for
The Zoom Fly 3 is best suited for more experienced runners willing to shell out some cash for a premium performance shoe, but not willing to break the bank on the less durable higher end models, and runner's looking for a top end distance training/racing shoe.
Andrew Leibowitz
Running Expert
Read the full review of Zoom Fly 3
or buy them here: Men / Women
Also consider

Nike React Phantom Run Flyknit 2

Weight
8.5 oz.
Drop
10 mm.
Category
Cushioning

Nike React Phantom Run Flyknit 2

Reasons to buy
  • Well-balanced, versatile ride
  • Durable React cushioning
  • Comfortable, seamless upper
  • Rocker midsole helps you transition through the gait cycle
“The Phantom Run 2 is a superb, everyday, neutral trainer and can hold its own against the best staple daily trainers on the market. Even though it looks like a casual shoe, the Phantom Run 2 is a serious running shoe with a versatile and supportive ride.”
Recommended for
The Phantom Run 2 is for the runner who wants a versatile and supportive neutral trainer which can be slipped on and off with ease.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of React Phantom Run Flyknit 2
or buy them here: Men / Women
Also consider

Nike React Miler

Weight
9 oz.
Drop
10 mm.
Category
Cushioning

Nike React Miler

Reasons to buy
  • Highly cushioned
  • Super comfortable
  • Great for longer runs
  • Reflective panels for dark runs
“The Nike React Miler is a completely new running shoe release designed to give a highly cushioned ride on your longer runs. If you're looking to go for miles on the road, this is an exciting shoe!”
Recommended for
The React Miler is for neutral runners, looking for a plush cushioned ride and abit of help with stability on longer runs.
Sarah Dean
5k Runner, Personal Trainer
Read the full review of React Miler
or buy them here: Men / Women
Also consider

Nike Legend React

Weight
9 oz.
Drop
9 mm.
Category
Cushioning

Nike Legend React

Reasons to buy
  • Peppy react foam
  • Inexpensive
“Nike’s Legend React shoe brings the new React foam into an affordable running shoe package while keeping a strong focus on a smooth ride and a smooth fitting upper.”
Recommended for
The Nike Legend React is for the seasoned runner who wants to try out a new generation of foam technology in a daily trainer while keeping a budget in check.
Frank May
Fast Runner, Triathlete and Engineer
Read the full review of Legend React
or buy them here: Men / Women

Nike Racing Series

There's no denying Nike's recent dominance in marathon racing. We like to think the runners had some credit too - but the sheer amount of victories show the commitment the Oregon brand has towards marathon racing.

First choice

Nike Air Zoom Alphafly Next%

Weight
7.4 oz.
Drop
4 mm.
Category
Racing

Nike Air Zoom Alphafly Next%

Reasons to buy
  • Highly cushioned midsole.
  • Very stable ride.
  • Breathable upper with excellent foot lockdown.
  • Explosive responsiveness provided by Zoom Air pods.
“The Alphafly Next% is the flagship Nike marathon racing shoe and is deserving of its premium price.    Light, breathable Atomknit makes its debut while the combination of ZoomX and a stiff carbon plate results in a propulsive ride second to none.     And if that wasn't enough, two giant Zoom Air pods in the forefoot give the Alphafly extra “pop”.”
Recommended for
If you're a runner looking for a highly cushioned race day option which is super responsive and very stable, the Alphafly Next% is a great choice.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of Air Zoom Alphafly Next%
or buy them here: Men / Women
Also consider

Nike ZoomX Vaporfly Next% 2

Weight
6.6 oz.
Drop
8 mm.
Category
Racing

Nike ZoomX Vaporfly Next% 2

Reasons to buy
  • Cheaper than the previous version (in certain countries)
  • Upper is more comfortable than previous versions
  • Propulsive springboard-type carbon plate
  • High level of cushioning
“The Nike ZoomX Vaporfly Next% 2 is still a superlight racing powerhouse with excellent cushioning and propulsion. What makes it so special is its unique forefoot geometry that provides a forward-tipping sensation during each toe-off.    This version is an upper-only update that improves the fit and comfort of the shoe. ”
Recommended for
If you're a runner with good form, looking for a super shoe that's best suited to fast paces, the Vaporfly Next% 2 is the shoe for you.
It shines on tempo, threshold and interval workouts but doesn't do easy paces very well because of its narrow rearfoot.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of ZoomX Vaporfly Next% 2
or buy them here: Men / Women
Also consider

Nike Zoom Streak 7

Weight
6.9 oz.
Drop
8 mm.
Category
Racing

Nike Zoom Streak 7

Reasons to buy
  • Lightweight
  • Snappy Responsive Feeling
  • Just Enough Cushioning For a Racing Shoe
“The Nike Zoom Streak 7 is a minor update to the previous version of the popular racing shoe. The updates are so minor that the seventh iteration of the Streak still provides a great responsive feeling with similar upper issues to previous versions.”
Recommended for
The Zoom Streak 7 is a great racing option by Nike for runners looking for maximum performance in a lightweight shoe for any racing distance, including up to a marathon.
It is a cheaper option for a race day shoe compared to other Nike offerings.
Andrew Leibowitz
Running Expert
Read the full review of Zoom Streak 7
or buy them here: Men / Women

Nike Trail Series

There are only three trail running shoes in Nike's offering - but they are very well rounded models that can take a lot of beating on different kinds of terrain.

First choice

Nike Pegasus Trail 2

Battery life
hrs.
List price
US$

Nike Pegasus Trail 2

Reasons to buy
  • Soft, breathable upper
  • Built-in faux gaiter prevents debris from entering the shoe
  • Stylish
“The Nike Pegasus Trail 2 is sufficient for road to dirt or grass trails; however, it does not perform well on most other types of trail terrain.While its trail-specific features provide protection, this shoe’s traction and stability are particularly unreliable on rocky or steep terrain making it impractical for any technical trail running.”
Recommended for
Katherine Takai
Long Distance Runner, former Sprinter.
Read the full review of Pegasus Trail 2
or buy them here: Men / Women
Also consider

Nike Terra Kiger 7

Battery life
hrs.
List price
US$

Nike Terra Kiger 7

Reasons to buy
  • Built for speed
  • Improved cushioning
  • Roomy yet has secure fit
  • Comfortable
“The Nike Terra Kiger was created with speed on the trails in mind. From toe to heel, the shoes are designed to let the runner blaze down dirt trails, paved trails and roads. The more technical the terrain, the less effective the Kigers can be. ”
Recommended for
Henry Howard
Ultra runner and certified running coach.
Read the full review of Terra Kiger 7
or buy them here: Men / Women
Also consider

Nike Wildhorse 7

Battery life
hrs.
List price
US$

Nike Wildhorse 7

Reasons to buy
  • Functional pull tab
  • Nice wide toe box
  • Comfortable upper
“With only minimal updates the Wildhorse 7 continues to be a reasonable choice for longer moderately paced runs. The Wildhorse continues to be unstable and sloppy on technical terrain keeping it more suitable to rolling pastures versus the wild Wild West.”
Recommended for
Jim Coulson
Fast Road and Trail Runner. Career Firefighter.
Read the full review of Wildhorse 7
or buy them here: Men / Women

Nike Free Series

Before minimalism was a thing and before barefoot runners started burning their shoes, Nike quietly introduced the Free range with a simple idea: a shoe to add to your training rotation, to stimulate your own foot muscles and balance. So while your daily training and racing shoes might protect you, once in a while you should introduce some extremely flexible shoe so that your feet can train naturally.

First choice

Nike Free RN 5.0 2020

Weight
7.2 oz.
Drop
6 mm.
Category
Lightweight

Nike Free RN 5.0 2020

Reasons to buy
  • Light, breathable upper
  • Highly flexible forefoot
  • Helps improve running form
  • Stable ride
“The Free RN 5.0 is a running shoe designed for short training runs, up to 5km, speedwork and drills. It can also be used for runners looking to work towards the sensation of barefoot running, with the protection of a shoe, and a little support. ”
Recommended for
The Nike Free RN 5.0 2020 is for the runner who wants a specialist trainer that will help them improve their running form and strengthen their legs.
Brandon Law
Marathon Runner and Shoe Expert
Read the full review of Free RN 5.0 2020
or buy them here: Men / Women
Also consider

Nike Free RN Flyknit 3.0

Weight
7.6 oz.
Drop
4 mm.
Category
Lightweight

Nike Free RN Flyknit 3.0

Reasons to buy
“The Free RN Flyknit 3.0 is a running shoe designed for short training runs, up to 5km, or for runners looking to create the sensation of barefoot running, with the protection of a shoe. Released at the same time as the Nike Free RB 5.0, the difference are mainly the upper and the heel drop. ”
Recommended for
The Free RN Flyknit 3.0 is recommended for runners who are used to minimal support when running. If you are not used to this type of shoe, it it recommended that you wear this for your day to day activities first, to get used to the new foot position and minimize risk of injury.
Sarah Dean
5k Runner, Personal Trainer
Read the full review of Free RN Flyknit 3.0
or buy them here: Men / Women

Nike Training Series

Nike makes great running shoes but running shoes are not the best choice for the gym. Here are Nike's training offerings.

First choice

Nike React Metcon Turbo

Weight
9 oz.
Drop
mm.
Category
Training

Nike React Metcon Turbo

Reasons to buy
  • Perfect harmony of stability, support and cushioning for all types of gym workout
  • Premium upper materials give comfortable support to the foot
  • React foam midsole provides best cushioning and responsiveness I've found in a training shoe
  • Superb looking shoe, great colorways and designs
“The Nike React Metcon Turbo is my new go-to shoe in the gym.  The training shoe has managed to combine stability, responsiveness and cushioning to be comfortable, stable and something I don’t have to think about whilst working out.  A superb all rounder I struggle to pick a fault in. All whilst keeping the weight down and looking fantastic.”
Recommended for
The React Metcon Turbo is for athletes and runners, training in a gym and looking for a shoe that can handle everything outside of their running training.
If you’re training with barbells, dumbells, or doing any type of plyometric of gymnastics work this is the shoe for you.
Sarah Dean
5k Runner, Personal Trainer
Read the full review of React Metcon Turbo
or buy them here: Men / Women
Also consider

Nike Metcon 6

Weight
12.6 oz.
Drop
4 mm.
Category
Training

Nike Metcon 6

Reasons to buy
  • New, lightweight, breathable upper
  • Solid feel under foot due to dual density foam
  • Fantastic support for lower body joints with lifting, building on solid base
  • Flywire lacing gives locked down snug fit, whilst wide toe box gives toes room to move around
“This is Nike's best shoe for the gym. From weight lifting to classes, HIIT, and treadmill running the Metcon can do it all. ”
Recommended for
The Metcon 6 is for people serious about their fitness and their strength training, who are looking for a shoe that can handle all exercises thrown at it.
If you want something you can lift, interval train, and go for short sharp runs in, this is the shoe for you.
Sarah Dean
5k Runner, Personal Trainer
Read the full review of Metcon 6
or buy them here: Men / Women
Also consider

Nike SuperRep

Weight
10 oz.
Drop
4 mm.
Category
Training

Nike SuperRep

Reasons to buy
  • Cushioned for fast movements in high impact and high intensity class
  • Does the job which they're designed to do
  • Made burpees and box jumps feel great
  • Technology in sole unit makes them unique
“The Nike SuperRep is a great training shoe if your preferred style of workout consists of high-intensity interval training, with moves such as burpees, lateral lunges, and mountain climbers.  If you love the HIIT endorphin buzz, and want to feel even more energy and bounce in your workout the SuperRep could be a great training shoe choice.”
Recommended for
The SuperRep is made specifically for a newly popular type of workout- the high impact, high energy intense class environment .
With the motto Rep, Sweat, Repeat and futuristic, chunky design they’re aimed at the style conscious gym goer who loves to put themselves through a tough sweaty...
Sarah Dean
5k Runner, Personal Trainer
Read the full review of SuperRep
or buy them here: Men / Women

An explanation of Nike running shoes technologies

Understanding the meaning and design principles behind the tech names will help you navigate through the catalog faster. Here’s an overview.

Upper technologies

Flyknit

Nike running shoes Flyknit Detail

Flyknit is a special woven fabric that makes the upper of a shoe feel like a sock, by placing yarns and knits strategically around the structure in order to support the foot of the runner when needed and leave it free everywhere else.

Flyknit running shoes are lightweight: a light yarn replaces multiple stitched or glued panels. Flyknit also allows for extremely precise upper fit, being able to seamlessly integrate tight-knit areas where support is needed and wide-knit areas to allow for flexibility.

Flyknit is environmentally friendly as it produces 60% less waste than traditionally constructed running shoe uppers.

This technology is Nike’s latest, so expect to pay a premium for Flyknit shoes.

Most notable examples of Flyknit shoes are the Flyknit Racer (as the name implies, a fast and light shoe for racing distances all the way to the marathon) and the Nike Free Flyknit (an extremely flexible and lightweight running shoe to strengthen and train the muscles in your feet).

FlyKnit Loft

FlyKnitLoft
FlyKnit Loft is a FlyKnit variation which is breathable and durable. It has 3 distinct layers which help keep the foot secure. It has a smooth, plastic-like feel and does not stretch.

FlyKnit Loft is used on the Infinity Run.

AtomKnit

AtomKnit

AtomKnit is a new, more advanced type of FlyKnit material. The difference between AtomKnit and FlyKnit is that AtomKnit is steamed and stretched. AtomKnit is extremely lightweight, very breathable and does not absorb water.

AtomKnit is only used on the flagship shoe, the AlphaFly Next%.

VaporWeave

VaporWeave

VaporWeave is an engineered, woven mesh with a smooth, plastic-like feel which is light and strong. Its main advantage is that it doesn’t absorb water so during a race, the shoe will not absorb sweat and weigh you down. VaporWeave is very breathable but doesn’t conform to the foot so creasing may occur.

VaporWeave is used on the VaporFly Next% and the Zoom Fly 3.

Engineered Mesh or Flymesh

Nike running shoes engineered mesh flymeshEngineered Mesh (sometimes called “Flymesh” by Nike) is a lightweight mesh construction that is – compared to traditional mesh fabrics – more breathable and is at the same time both more durable and flexible.

Engineered Mesh features more prominent perforations than traditional mesh. It is a completely different construction than the previously mentioned Flyknit and shoes with Engineered Mesh usually have a lower price-point.

Engineered mesh is used on the Pegasus 37, Miler, Vomero 14, Downshifter 10 and Winflo 6.

An overview of Nike running shoe sole and cushioning technologies

Midsoles of running shoes are made of foam. Each company has their own trademark foam mix that tries to achieve the following: be as lightweight as possible, be soft in order to absorb the impact with the ground, be elastic (in order to compress on impact and release propelling you forward), be durable (foam does deteriorate with use, so all foam materials need to be engineered to maintain its characteristics for a decent amount of time).

React Foam

ReactFoam

React is a styrene-based material which is a synthetic rubber. It is lightweight, durable and resistant to temperature changes. React doesn’t have sink-in softness but has a dense, rubbery feel with a noticeable spring.

React Foam is used in the Pegasus Turbo 2, Odyssey 2, Vomero 14, Zoom Fly 3, Infinity Run, Terra Kiger 6, Miler and Pegasus 37.

Nike ZoomX Foam

ZoomX

ZoomX delivers Nike Running’s greatest energy return. It is featherlight, cushioned, springy and great at preventing foot fatigue. ZoomX is quick to compress and snaps back instantly.

ZoomX is used in the VaporFly Next% and AlphaFly Next%.

Fly Plate

FlyPlate

FlyPlate is a light carbon-fibre plate which delivers a snappy sensation with every stride. It provides a propulsive feeling to increase your pace.

FlyPlates are used in the AlphaFly Next%, the VaporFly Next% and the Zoom Fly 3.

Cushlon

Cushlon is a mix of Phylon and rubber additives that makes it lightweight and responsive.

Nike Air

NIKE_Air
Everybody knows Nike Air. That’s how Nike got big in the 80s in the first place. But do you exactly know what Nike Air is ?

Nike running shoes in the “Air” category often use Cushlon foam in their soles. Soft and resilient, this foam has 2 limitations: it is quite heavy (as most foam is) and it is not as “bouncy” as many runners expect their shoes to be.

The solution? Cutting off areas of the Cushlon-foam-made midsole and filling them up with plastic bags filled with “Air” (Nike’s secret gas compound). What this achieves is to reduce weight (by replacing the heavy foam with a very lightweight “airbag”) and to increase cushioning (being these airbags softer and springier than the Cushlon foam).

Depending on the shoe, you can have Nike Air bags in the heel, the toe, or both.

Air bags come in 3 formats: Air, Air Max and Zoom Air.

  • Nike Air -> the most common, medium sized air bags that fit well especially under the heel.
  • Air Max -> very thick and highly cushioned bags of air. In our opinion too unstable for proper running, mostly used on lifestyle shoes.
  • Zoom Air -> the thinnest units, ideal to fit in low-profile shoes. They were initially developed for soccer shoes, where normal Air bags would not fit inside the ultra-thin sole

Nike Free

nike-free-alt-closure-run-sqdrnbl-hypbl-cybr-free-flex-1-610x406

Nike Free is a concept. Started around 2005, the idea was to create a shoe that is so flexible that leaves the foot completely free to move in the most natural way.

Some people object that the Frees are still very cushioned shoes, therefore preventing the runner to have a true feeling for the ground below them.

While this might be true, the extreme flexibility of the Free sole unit, combined with very open-mesh and unconstrained upper make for a treat.

What do the numbers next to a Free shoe mean?

Nike abandoned the use of numbers in the Nike Free line in 2016, when they completely revamped the category.

Originally Nike Frees came in different versions, depending on how flexible they were. Their flexibility was ranked on a scale that goes from 1.0 to 10.0, where 1.0 means “bare feet” and 10.0 is a traditional running shoe.

In 2016, with the coming of the new auxetic construction, the Nike Free range is completely new and the numbers are gone. We’ll go through the line and the models in a minute. Keep reading!

Nike Free Auxetic Construction

Nike Free Auxetic Construction

The new principle behind the Nike FREE line of running shoes is called “auxetic design”.

When your foot hits the ground, it expands both in length and width. Picture bouncing a ball on the floor: it squeezes and deforms because of the impact, then the opposite happens while it bounces back.

Nike engineers were looking for a way to design a midsole so that it would expand in both directions during the foot strike. The issue is that most materials, when stretched in one direction, become smaller in the perpendicular direction. Again think of an elastic band. If you pull it to stretch it long, it will most likely become narrower in the middle.

The auxetic design, characterized by the triangular cuts you see in the picture, allows the sole to do that. A stretch in one direction will equate to a stretch in the other.


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