The Nike Infinity Run 4 (or RN 4) is the first major update to the line, with an all-new midsole foam called ReactX being the headline change compared with the Infinity Run 3. This new foam is softer and returns more energy, but the new shoe is also a fair bit heavier than past editions. Jane and Nick have been out for their first runs in the shoe and give their early impressions here.

00:00​​​​ – Intro
00:13 – Design & Key Stats
02:09 – How’s The Fit?
04:24 – First Run
08:12 – Early Verdict

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Hello and welcome to run testers my Name's Nick and this is our first run Review of the Nike react X Infinity Run 4. [Music] So the Infinity Run 4 is the first major Redesign of the infinity line since it Launched a few years back it's still a Shoot this is someone for similar Purpose though which is to be a stable Neutral shoe with lots of cushioning Designed for easy runs and to also be a Very good option for newer Runners just Starting out and Sport you want a lot of Cushioning it's 160 in the US which is The same price as the previous model but In the UK we seem to have a little bit Of a price jump it's now 155 pounds it's Also had a big weight jump now 345 grams Or 12.2 ounces in my UK size 9 which is A us-10 this model has been getting Heavier with every generation but this Is still the very jump from the Infinity Run 3 which was 310 grams in my size so I've got a nine millimeter drop and the Stack height is 39 millimeters at the Heel and 30 millimeters at the forefoot You've got a Flyknit upper again with Loads of padding around the collar and On the tongue there the big plastic heel Clip that you saw on the infinity line In the past is gone but there is still a Small internal heel counter and this Shoe has a couple of other methods of

Making sure it's nice and stable you've Got big side walls of foam on the Midsole that your foot sits Within and Then a very wide base even wider Especially around the midfoot than the Previous model which did taper a bit in The center of the shoe but you don't get That so much with the Infinity Run 4. Mike also says that the fit is going to Be wider than the previous shoe Especially in the toes and it's either They water a pillared liner to the front Of the toe box to uh keep some water off Your feet on wet runs but obviously the Biggest change of the shoe is the new React X midsole which uh Nike says it's Got a much lower carbon footprint than React foam and also it delivers more Energy return an extra 13 of energy Return in fact compared to standard React foam it's certainly softer and Squishier to the touch than the react Foam you've still got a rocker design as With the previous models of the shoe and Then you've got a new waffle tread Outsole which you've seen some of Nike's Other shoes as opposed to the blotchy Style About Soul we had on the infinity Line in the past to fill out so it Should be really good for durability Obviously add a little bit of weight to The shoe to have a fairly thick full Layer outsole like this but the benefits Of it will be felt in terms of grip and

The durability like I say Hi I'm Jane one of the Run testers and It is my first run with the Nike react Infinity Run for this arrived this Morning and I've taken it out on a kind Of really gentle Easy run Um just to kind of give it a test so Here are my thoughts so far start with The fit I would say these come up a Little bit snug these are a US seven and A half UK five which is my normal size In Nike running shoes and they do feel They are pretty Just a little bit snug so think if You're between sizes maybe size up in These Um the Nike say they've updated the Upper they say it's water resistant on The inside so if you run for a puddle Your feet aren't going to get soaked and It's they say they're best flying it Yeah it definitely does feel I feel like We've moved away from like the kind of Light knit whether you can almost see Your socks through the through the shoe So definitely more of a kind of tighter Thicker upper again but you know they They fit they fit fine they fit Comfortably there's a lot of padding Around the collar and the tongue and I Think they look really cool I like what They've done with the design I think They've kind of they've definitely

Changed it from the last few versions You've still got this quite pronounced Rocker but just it looks it looks Different and you've still got the react Foam but I do I do think they look Really cool out the box so the fit of The shoe Nike recommends going half a Size up on some materials I have which I Wouldn't recommend I would go true to Size this is my normal size eyes uh for Nike across the board the uk9 and US 10 And if anything I've got a little bit Too much room I could certainly notice The extra room in the toe box and it Feels roomy around the midfoot too Compared to the Infinity Run 3 which fit Me really well in my normal size I have Quite a narrow foot so that's probably Where the differences are rising like I've got a bit more room because of my Narrow foot and if you have a wide foot I'm sure you'll get on better with the Infinity Run 4 compared to past models Because it does have a lot of extra Width in the toe box which doesn't taper Quite so aggressively as the Infinity Run 3. overall though I've been pretty Happy true to size the hold has been Good around the midfurn here on my run So far I could potentially go upside Down just because I've got that extra Room in the toy box but I don't feel the Need to so yeah I'll stick with your Normal size for running shoes and Nike

Shoes [Music] Thank you so first run review I've Actually done three runs in the shoe Although two of them very short don't Really count I did a quick uh 20 minute Run on the treadmill with the earlier to Test out a new feature on peloton's Treadmill and then I did my run for the Day which was an easy five miles in the Center of town before coming back and Doing a little poodle around the block Wearing both the Infinity Run 4 and 3 to See how they compared now paper I was Not very excited about the shoe is Really heavy uh that's one of the Heaviest weights I've seen for my size Apart from maybe the ultra boost 22 or Something like that for the last few Years so this new phone was really going To have to pack a lot of Bounce I think To try and create a nice feeling on the Run and so far I'm not really sold on it Uh like it's certainly knows to be Squishier and softer than the foam on The Infinity Run 3 and past models get a Little bit of bounce back but you're not Getting a lot of bounce back it feels More almost you're sinking in and then Getting lost a bit a little bit in that Foam upon Landing it's a it's a okay Sensation but it certainly feels quite Bottom heavy as a shoe to me and I don't Really think you're getting a lot of pop

Back from it if you're going to try not The pace at all like on the treadmill I Was able to do some Sprints and stuff Like that and I did speed up a little Bit on stages of my run but overall it's Very much a shoe that's going to be Designed for easy plots cruising along Um just enjoying the benefit of all the Cushioning of the heel in particular it Does feel less cushioned under the Forefoot and I think on stats alone it Says cushioned as the Infinity Run and The drop is the same but it feels like a Higher drop almost and it really feels Like that cushioning runs out quick at The front of the shoe and I think over Long runs if you are a heel Striker like Myself coming through onto that forfeit You might get a little bit of thought For fatigue from the shoe but I didn't really get that stay on short Runs it certainly felt very cushioned at The heel and midfoot with that big stack Of react X foam but when running with Both shoes side by side it's noticeable How much I prefer the fit of the Affinity Run 3 that's probably because I Do have a narrow foot it really does Hold my foot really nicely I think it's One of the most Pleasant upper Experiences I've had from any shoe the Infinity Run 3 and then when you're on The run the older shoe feels a bit Firmer but you really notice the rocker

A bit more from me I think you can Actually get into a nice rhythm with the Infinity Run 3 whereas you do sink in a Little bit more with the Infinity Run 4 And that negates the rocker effect I Think a little bit whereas with the Infinity Run 3 you're really not getting Much from the foam in terms of energy Return and explosive feeling but I do Feel like I can get into a nice sink With the rocker and actually that means It works a nice range of Paces sometimes Because you are almost just skipping Along the grounds the phone's not giving You a lot but the huge geometry works Really well whereas I don't think the Foam and the geometry of the Infinity Run 4 have really worked together so Well for me yet like it just feels like I'm sinking in a bit losing a bit of The Rocker and then not getting a huge Amount from the phone so yeah it wasn't The greatest first run it's probably the Upshot of all of that but tell you more Testing to come it certainly feels like It's gonna be a nice cushioned shoe and It doesn't seem to have lost anything in Terms of stability but I'm not sure the New phone really adds a lot to the Overall experience yet so they're on Test as I said I wore this for a really Easy run and I kind of think that's what Your this shoe was designed for it's Definitely a heavier shoe I've weighed

It at 260 grams so you know it is Heavier it's heavier than the Invincible It's heavier than the peg underfoot it Feels a bit like the ultra boost the Ultra boost 23 it's not the same Boost Phone but the reactor is definitely that Like firm of foam but it's not a Lightweight shoe so I think It's a you know it's definitely an Everyday shoe but personally if I'm Running if I'm going out for an everyday Run a really easy mileage run I want Something like the Invincible that's Super plush or the Asics Gel Nimbus 25 Do you mean I want that like sink in Comfort which you don't get in this shoe That said You know it's still the same Infinity We've seen for the last few years and if You're a fan of that shoe you're you're A fan of the react foam you'll like it I like the feel of it I just don't I Don't know for the money I don't know Where this would sit in your collection Foreign Be doing a lot more running in this shoe I want to test it for different stuff You know yes it's kind of an everyday Shoe but I want to test it on the Treadmill I want to test it for kind of Trying to run a bit faster in it but my First kind of impressions are I didn't Hate it but I didn't love it I wasn't Blown Away by it and I think for 160 or

154 pounds there are kind of other Everyday running shoes on the market That are probably a similar price point And a bit more exciting Um that said I feel like again I feel Like I did with the ultra boost light Where I'm like this just might not be my Shoe and actually there is a place in The in the market for this shoe there is A runner that would love this shoe and I'm looking forward to doing some more Testing and some more miles than it I'd Say if you love The Infinity Run 3 You'll like this it does feel different I think it looks a lot different I think It looks amazing so I think if you're a Fan of the infinity line you it's still Got everything you'd love about it it's Still got the kind of rocker still got The react foam still got the Flyknit Upper just in a kind of cooler looking Package so It's still the infinite to be known love And I'm going to be definitely doing More testing in it yeah we're not say Anything too excited about the shoot at This stage because it's just our first Run review but I don't feel like the Improve the changes to the Infinity Run 4 have made it a better running shoe as Yet but the new foam is there it's good It's got a lower carbon footprint Obviously but at the same time I'm not Really sure you're seeing the benefits

Of that extra energy return it feels That that softness the squishiness that They've added with this foam means it Loses a little bit of the smooth Transition that I used to get from the Infinity Run 3 with its firmer and Optically exciting react foam but it did A job last a long time I'm sure this Will still be a nice long lasting shoe But I'm not sure the ride really Benefited from the changes made because The weight gain is obviously substantial And I'm not sure the new phone really Does enough to counteract that but it Will be a comfortable option I think for Neurons in particular with a load of Heel cushioning to give that protective Feeling and be more bit more comfortable On your early runs in the sport it's Still a pretty good looking shoe I mean I think every slightly prefer the look Of Infinity Run 3 but it's a shoe that's Designed to have a bit of crossover Purpose and I think it will still have That but so thought their changes Haven't really wowed me or necessarily Improved the shoe for my money and the Other thing to quickly talk about Obviously we'll dive into this much more In our full review is where the infinity Stands in Nike's range like there are Quite a lot of cushion tubes in Nike's Range now like the Invincible is not to Everyone's taste but it is you know a

Shoe and identity a very soft very Squidgy shoe with all that sumex foam in The middle it has a bit more bounce a Lot more bounce on this react Expo for Sure so that's one option then the Pegasus 40 is a lot cheaper than the Infiniti and I think just a far better Ride it's still cushioned and Comfortable maybe not as cushioned as The Affinity but still does that job and It has a much better transition onto Your toes and you know more versatility For a nice variety of runs there are two Shoes that have strong have a stronger Identity I think than this new Infinity Which just doesn't feel too much like The old one and doesn't necessarily feel A lot better like I say more to say on Those comparisons down the line