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Newton Gravity 13 Review
By Matthew Klein & David Salas

Despite being a company that originally introduced something drastically different, Newton has been fairly consistent over the years. They have maintained many of their stand out features, including their ART (Action Reaction Technology) lugs in the forefoot, their lower heel offsets, the lighter weights and moderate stack heights. The Newton Gravity is their flagship neutral training shoe that has maintained many specifications but experienced continued gradual improvements over now 13 versions. The latest version makes mild changes to the midsole with a new material that softens the ride. This occurs especially in the forefoot, which makes the heel drop feel less aggressive and makes for a smoother ride in comparison to past versions. 

Newton Gravity 13
Price: $185 at Newton
Weight: 8 oz, 227 g (men's size 9), 6.8 oz, 193 g (women's size 8)
Stack Height: 23 mm / 20 mm
Drop: 3 mm
Shoe Purpose: Performance Trainer

Pros: Comfortable Upper, Faster Ride, Smoother Forefoot Lugs, Stable Forefoot
Cons: Expensive for Lower Stack Shoe


The Newton Gravity 13 is a light performance trainer with a comfortable upper and a uniquely lugged forefoot. A comfortable upper sits up top with a slightly wider forefoot and a slightly snug heel and midfoot for a natural leaning performance fit with or without socks. The new Newtonium-T midsole makes for a slightly softer ride and more compressive lugs that provide a balanced ride no matter where you land. Maintaining its place as a lower drop, performance shoe that can handle easier efforts to races, the Newton Gravity 13 continues its trend of subtle updates while remaining consistent for long-time fans. 

: Newton Gravity+, Newton Distance 13
PAST MODEL: Newton Gravity 12

(To learn how a shoe should fit, check out our full podcast on fit by Matt Klein.)

Matt: The Newton Gravity 13 fit me true to size in my normal men's US size 10. The fit is consistent with prior versions, featuring a slightly wider forefoot, a normal to snug midfoot and a normal heel. The forefoot fits slightly wider with plenty of stretch from the upper. The volume is on the lower side but the stretchiness of the upper does allow for some wiggle room vertically. The midfoot fits normal to slightly snug. I did not have to tie the laces that tight as the slightly thin and well gusseted tongue helped secure my foot. The heel fits normal with thin heel collar padding and a moderately stiff heel counter. The counter feels stiffer than prior versions and I did notice it. Those with heel sensitivities will likely not do well in this shoe while those who like stiff counters will do great. Fortunately, there is some mild padding at the rearmost portion of the shoe that does protect the heel a little. Despite the counter, sockless running is fantastic in this shoe. The upper is breathable and the inner liner is comfortable against bare skin. Half of my mileage has been without socks and I have not had any blisters. The insole is removable, so those who want to replace it or use orthotics will be able to do so. 

Typical Size: Men's US Size 10
Shoes that have fit Matt well: Saucony Guide 17, ASICS Kayano 30, Hoka Gaviota 5, Saucony Endorphin Elite, Nike Ultrafly
Shoes that have fit snug: Hoka Arahi 7, Saucony Kinvara 14
Shoes that have fit large: Salomon S/Lab Phantasm 2, Altra Timp 5

The Newton Gravity 13 fits true to size in my men's 9.5. Newton uppers have traditionally fit my foot well over the years. They have maintained a very similar fit profile in this model as well. The classic air mesh is here to stay and gives a very breathable and soft upper material. There is a little stretch to it, but not so much that it loses its structure. The fit dimensions feel pretty dialed in throughout with the heel and midfoot being a normal width, and the forefoot being normal to slightly wide. The tongue is moderately padded and does a good job of preventing biting from the laces. There is a lightly padded heel counter that is curved well and prevented any heel pressure or irritation. I've always found the Gravity line to have good lockdown and things are no different here. This is still one of my favorite uppers and fits on the market. Relatively simple but effective.  

David's Typical Size: Men's US Size 9.5
Shoes that have fit David well: Nike Vomero 17, Saucony Ride 16, Puma Velocity Nitro 3

Shoes that have fit snug: HOKA Arahi 7
Shoes that have fit large: Salomon Aero Glide

Doctors of Running Checklist

Is This a Good Shoe for Walking: Somewhat
Is This a Good Shoe for Standing: No
Is the Forefoot Flexible: Flexible at Toes and Midfoot but less so at Forefoot
How Flexible is the Shoe: Fairly Flexible
Is This a Good Heel Bevel: Mild Bevel but Doesn't Need It
Recommended for Haglunds: NO
Recommended for Sockless: YES
Durability Expectation: Above Average


Matt: The Newton Gravity 13 is a forefoot lugged performance trainer for those who want a moderate to lower stack height with a low heel offset. The midsole features a new TPEE material called Newtonium-T that provides a slightly softer ride compared to previous versions. With the lower to moderate stack height, the ride is still slightly firmer compared to other shoes. However, this softens the forefoot ART lugs, which makes the 3mm drop feel less like a negative drop than prior versions. The lower heel offset is still noticeable, so those not used to this shoe should slowly transition into using it. The heel transition is fairly smooth despite having almost no heel bevel. There is a little bounce forward when landing at the heel. This transitions into a fairly flexible midfoot. Once you hit the forefoot, the combination of a forefoot PEBAX plate and the lugs become apparent. This creates a stiffer place to push off from but the front part of the forefoot after the lugs is flexible. This allows for a quick but easy transition forward. Despite the stiffness where the lugs are, the flexibility does require adequate toe motion for forward progression.

The lower weight (8 oz men's size 9) combined with the snappy forefoot, lower ride but slightly softer cushioning allow this shoe to transition between a variety of paces. I have done easy runs, fartleks and tempo intervals in the Gravity 13. It felt better the faster I went, but easy runs felt better as the shoe broke in. As I am mostly running in moderate to higher stack height shoes, I had to get used to the lower relative ride of the Gravity. Once I did, it was easy to transition through a variety of paces. For most people, the more aggressive features will make this a moderate-distance shoe for uptempo and faster efforts. The weight is similar to many racing shoes and lightweight trainers on the market, albeit with a different stack height. It is a great alternative to super shoes for those trying to save those for race day and get their legs to get more from their workouts, yet still feels fast when the pace picks up. For easier efforts, it feels fine once you get used the unique ride. The lower stack height does limit the use of this shoe to shorter to moderate distances unless you are adapted to this type of shoe.

The outsole traction and durability have been extremely good. While this is a road shoe, the lugs grip well on non-rocky, dirt trails (I would still use the BOCO AT series instead for true trail). The traction is excellent on both wet and dry road, so regardless of climate you can trust this shoe. Rocks are the nemesis of the Gravity as they can easily get stuck between the forefoot lugs. This is immediately uncomfortable, so avoid areas with gravel. The outsole durability is great after 20 miles of fairly hard use. I do not see any wear on the outsole and expect an above-average number of miles for both a lightweight trainer and traditional training shoe.

David: The Newton Gravity 13 performed well for its purposes. This shoe is aimed to be a daily trainer with enough range to go long distance and also into speedwork. Newton shoes have always felt pretty good at up tempo paces, thanks to the ART forefoot lugs. The shoes always have a very forefoot forward feel to them when you get up onto your toes.

The Gravity 13 updates include a more compliant and responsive foam underfoot.  I will say the foam feels softer than traditional Newton models. The shoe does still ride pretty low to the ground though and you can feel nearly everything under your foot still. For how low the shoe feels though, I will say the protection underfoot is pretty good. The shoe has a relatively flat platform, in that the 3mm drop is made into a 0mm drop with the forefoot lugs. I will say that is noticeable when you are running. The shoe wants you to shift forward and lever off of the lugs. Once you get the rhythm of the shoe down it actually pretty nice and lively. In the past I have felt Newton shoes have worked my calves really hard, but it seemed to be more mild in this current version of the Gravity. One thing that that the runner definitely needs though is calf muscle length, ankle dorsiflexion mobility, and eccentric control through that region because your ankle will definitely move through a larger range of motion under load at that region. This shoe is also very flexible through the midfoot, and so that larger ankle range of motion angle is even more evident.

One thing I found interesting is that the ART lugs feels a little more compliant in this model for some reason. They seem to have a tad more splay. I notice this with sharper turns or when running over things with uneven height on footing like rocks. You will feel them move slightly when pivoting over them. This normally is not a big deal, but I have had a couple situations of rocks or small hard fallings from trees getting stuck in the lugs. You can feel it there like a little ball in between the lugs and it can make things a little clickity clackity. Everything in consideration this is probably my favorite Newton Gravity so far. I do wish for the lug system to be a little stiffer though, especially to accommodate the flexible midfoot.

(Learn more about stability in our full guide)

Matt: The Newton Gravity 13 is a neutral training shoe. A stability version of this, the Newton Motion 13, is available. The Newton Gravity does have a stable forefoot thanks to the wider shape, lugs, and PEBAX plate. There is a noticeable stiffness to this area that easily pivots you forward. Those with mild stability needs will likely do fine. The heel and midfoot are both quite neutral. There are no sidewalls or major forms of guidance. The midfoot is fairly narrow and flexible, so those with midfoot stability needs should definitely look at the Motion 13.

The Newton Gravity 13 is definitely a neutral shoe. The platform is somewhat narrow and there really aren't any extra measures for creating a stable environment. The lugs inherently seem to help with a little forefoot stability though. I find that my forefoot collapse is less these, especially medially, due to the extra stiffness from the ART lug pattern. Outside of that though this is very neutral. They do have a stability specific model called the Motion. 

Thoughts as a DPT: What Happens To Your Calf Muscles In A Negative Drop Shoe?
By Matthew Klein

The geometry of many Newton shoes often make them feel like their heel offset is far lower than listed. 2-3 mm drop is common throughout the range (with some exceptions), but the design of the lugs can not only feel like a negative drop, but may actually put you in that position at certain points of the stance phase of your running gait. Fortunately, the addition of the softer midsole material does seem to make the lugs in the Gravity 13 compress more, allowing for a slightly less aggressive feel compared to other versions. We have previously discussed how heel drop is dynamic in nature, not a static measurement. Depending on where you land and where you are putting force during certain points of the gait cycle, the drop may be higher or lower. A heel striker will create a lower drop shoe at initial contact and a higher drop shoe at toe off. A forefoot striker will create a higher drop shoe throughout most of their gait cycle, simply due to compression of one part of the midsole compared to the other. Being a heel striker can make lower drop shoes difficult as compressing the heel in certain shoes can make them actually become negative drop shoes for a brief time.

This is challenging for many people not only due to more extreme ankle dorsiflexion range of motion requirements, but far higher muscular demands from the calf and plantarflexor muscles. All muscles function differently at different lengths. Most muscles function optimally in their middle range, while often producing less force at more extremes (both short and long). The calf muscles are unique in that they actually produce more force the more lengthened they are (Manal et al., 2006). This is great to know for those trying to strengthen their calf muscles may find that doing heel raises off a step may be a good advanced progression (if appropriate) when an additional challenge is needed. It is also important to realize that the greatest amount of force the calves produce is not during the push off phase when the ankle is pointed (in a ton of plantarflexion) but actually when it is underneath you and bent (a ton of dorsiflexion). The greater amount of dorsiflexion you go into, the higher the demand on these muscles.

That is one of the many reasons that lower or zero drop shoes can make your calf muscles more sore if you are not used to them. This becomes even more challenging in shoes that take you through a negative drop position (whether intentional or not). For this reason and more, those who are interested in lower or zero drop shoes like Newtons should spend adequate time preparing their calf muscles for both the strength requirement as well as the range of motion requirements. Easing into these shoes can help, but making sure you understand the force output requirements from these muscles may help you better prepare them to reduce your risk of injury. 


Manal, K., Roberts, D. P., & Buchanan, T. S. (2006). Optimal pennation angle of the primary ankle plantar and dorsiflexors: variations with sex, contraction intensity, and limb. Journal of Applied Biomechanics22(4), 255-263.


Matt: The careful changes to the Gravity 13 will keep long time fans happy. The slightly softer midsole balances out the lugs while adding a little more comfort. The stack height is low enough and the midsole compresses well enough that I do not need to comment on a heel bevel. However, I am concerned about how much sagittal plane flexibility exists in the midfoot. There are two flexible grooves in the middle of the shoe right before the plated forefoot. There are no sagittal plane joints in the midfoot and this may cause problems for people who are sensitive to motion in that area. I would consider extending the plate back into the midfoot and removing those flex grooves. This will more appropriately model the biomechanics of the foot and the natural way forces are transferred between different parts.

My main recommendation for the Gravity 13 would be to play with the ART lugs some. The softer midsole is nice, but does show for a really flexible midfoot. I didn't mind the increased flexibility, but I do think it trinkled into the forefoot compliancy. If the ART could get reinforced a little more and hold its structure more that would create a stiffer and more responsive forefoot to counter act the flexible platform elsewhere. That could happen from lengthening the stiffening agent, or making the midfoot a tad less flexible via foam or less grooves.


Matt: The Newton Gravity 13 is a performance trainer for those who want a lower stack height, lower heel drop, lugged forefoot shoe with a comfortable upper that works with and without socks. The upper will work best for someone who wants a normal fit with a bit of extra room in the upper and a lower volume fit that is slightly offset by some stretch. The ride will work best for those who want a faster ride, lower drop and a shoe they can pivot off the forefoot. The durability of this shoe remains great, slightly offsetting the extremely high cost of this shoe. It is great that there is a $5 drop, although $185 is still expensive for a shoe like this.

The Newton Gravity 13 is a shoe for someone that wants a very nimble and relatively low riding experience. The foam has enough cushion for daily miles (or more) if someone is trained up to it. Runners who like more minimalist or flexible shoes will like this, as your ankle certainly moves through large ranges of motion in the Gravity 13. The shoe is nimble at all paces which feels nice and adds some versatility as well if you can control your mechanics.


Fit: A- (Breathable, lower volume, slightly stretchy upper with wider forefoot. Stiff counter in rear may be problematic for those with sensitivities)
Performance: B+/A-
 (Aggressive ride that works better the faster you go. Softer lugs not as aggressive and slightly softer midsole now more comfortable for some easier efforts)
Stability: B/B+ [Neutral] (Stable forefoot with neutral midfoot and heel)
Value: B/B- (Good durability but extremely expensive for lower stack shoe that has been somewhat similar over 13 versions)
Personal: B- (A fun but expensive tool. Limited use for me due to the lower stack height but great for shorter efforts where I want to work on a more forward footstrike. Not sure about midfoot flex grooves and flexibility)
Overall Design: B/B+


Fit: (Another dinger upper from Newton. Good fit and dimensions without sacrificing comfort and breathability. There is a stiff counter, but its done well.)
Performance: B+/A-
 (The more forgiving foam does increase versatility a lot, though the ride is still quite forward pitched in a way that most won't be able to take it long. The ride is smoother at all paces than previous. Flexible midfoot and forefoot can feel a tad odd if footing not great.)
Stability: B [Neutral] (Very neutral through heel and midfoot, especially with flexibility, though forefoot stability is pretty good)
Value: B (It's consistent pricing for Newton shoes. It should last you pretty well, but $185 is a lot for any shoe.)
Personal: B/B+ (Despite the midfoot flexibility comments, I like this shoe a lot. I just need to develop my own eccentric calf strength and control to control the larger ranges of motion needed for more usage.)
Overall Design: B/B+ 


Newton Gravity 13
Price: $185 at Newton

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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, Santa Barbara, Danbury and Stevens Point areas, we 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 Newton Running for sending us pairs.  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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