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Newton Running Gravity+ Multiple Tester Review
By Chief Editor Matt Klein, Senior Contributor David Salas and Contributor Andrea Myers

Newton has been making some big efforts in 2021 to use sustainable and eco-friendly materials. They continue this tradition by progressing the Gravity series with a new design underfoot. Newton reworks the XPS plate to allow for a more fluid transition upon loading while also updating the midsole to a foam they call NRG+. The result is a lightweight, nimble, and responsive option to add to the lightweight trainer/racer category. 

Lateral view of the Newton Gravity+. A white upper with a black, red outlined Newton logo. PLUS written on heel

Specifications for the Newton Gravity+ (per Running Warehouse)
Price $190.00

Weight: 8.6 oz / 244 g (men's size 9) 7.4 oz / 210 g (women's size 8)
Stack Height: 32 mm / 29 mm
Drop: 3 mm 
Classification: Lightweight Neutral Trainer/Racer 


Matt: The Newton Gravity + is a neutral uptempo/lightweight daily trainer that evolves into a faster and more eco friendly shoe. The new NRG+ midsole provides a more forgiving and responsive ride while the XPS+ plate in the forefoot provides a stable toe off. An extremely comfortable upper sits up top that secures the foot regardless of whether you decide to run with socks or not. The Newton Gravity + is a faster and more accessible option for those interested in trying Newton. A lightweight trainer that works great for workouts and longer races for those who can handle lower drop shoes. 

David: The Newton Gravity + is a neutral lightweight daily trainer that continues upon the eco-friendly model Newton has been striving for. The Gravity + differs from the Gravity 10 - the brand's neutral daily trainer - in that it features a new midsole named NRG + that is still supplied with sustainable materials. The foam is a tad softer and more responsive. The shoe is a lightweight training shoe that could also function as a racing or workout shoe for some as well.

Andrea: The Newton Gravity+ is a neutral, lightweight 3mm drop shoe that shines at higher speeds. The forefoot lugs come alive at faster paces and provide a feeling of being propelled forward that is very different and more natural as compared to super shoes. The NRG+ midsole provides lightweight, responsive cushioning and the mesh upper is one of the most comfortable I’ve tested. This shoe is ideal for uptempo intervals or races for runners accustomed to lower drop shoes.


Matt: The Newton Gravity + fits me true to size in my normal US men's size 10. The upper is incredibly comfortable with or without socks. I have run up to 10 miles in this shoe without socks and not had any chaffing. The lightweight mesh is breathable, light and soft. The fit is normal to slightly wide. The heel and midfoot fit on the normal size. The laces can easily snug up the upper more at the midfoot and I have had not issues with security at the heel. I have not had to lace lock the heel and the slightly flexible heel counter is stable but not irritating. Those with sensitivities to heel counters should still be a little cautious, but I have had no issues even while running sockless. The forefoot is a little wider, particularly with the extra give in the upper. I have not had any security issues despite this extra width and flexibility as the midfoot locks the foot down well. Turning at high speeds on the track and on roads not been a problem. This upper continues to be one that "disappears" and lets me focus on other things. Overall the upper is fairly minimal but locks the foot down well. 

David: I have always loved Newton uppers and fit. The upper is very cozy while still being breathable and supportive throughout. The heel and midfoot are normal width with a slightly wide toe box in the forefoot. There are minimal overlays throughout and the feeling of the upper is very sock like. The upper has a little bit of stretch to it but not enough to cause any foot translation in any specific direction. The tongue is lightly padded and holds the dorsum of the foot well without any slippage problems. Overall the upper feels very balanced throughout and pleasant on foot. There is a semi rigid heel counter present that is very lightly padded. I had zero irritation in this region it feels that the counter is there more to just support the structure of the shoe in that region. Otherwise it is pretty minimal with on foot feel.

Andrea: The Newton Gravity+ fits true to size in my usual women’s 9.5. The recycled mesh upper is soft, well-ventilated, and does not stretch. I really liked how the upper became unnoticeable the moment I put the shoe on. The mesh is so breathable that I definitely felt the cold air on a couple of 25 degree days, but my feet quickly warmed up as I got going. The toe box and forefoot are on the wider side, providing sufficient room for toe splay, but not so much room to allow for foot translation in the shoe. There is a firm external heel counter and a lightly padded heel collar that I found very comfortable. The tongue is gusseted and lightly padded and stays in place securely. The laces are flat and provide excellent lockdown without heel lock lacing. Overall, this is one of the most comfortable shoes from a fit perspective I have tested.


Matt: Although similar in outward design, the Gravity + has a different ride than the normal Gravity series. The ride is slightly firm, but is much softer than most Newton Models. The NRG + midsole softens the ride and makes the lugs slightly less noticeable. The 3mm drop is apparent when running in this shoe, but it feels less like a negative drop shoe compared to the Gravity and Motion models. The lugs can still be felt and engage most at uptempo paces. Sprinting and faster workouts feel amazing in these, with the lugs and the XPS + plate powering you through toe off. The heel is more forgiving due to the slightly softer sole and action-reaction tech in the rearfoot. I cannot see it specifically, but the rearfoot has far better cushioning while still being firmer and stable. This is still a Newton shoe, so getting up on the forefoot feels a little better. The firmer ride still gives a large amount of proprioceptive input when landing, which has increased my cadence on every run I have used these for. This is the first time in years I have been able to use a Gravity or Motion into double digit runs without excessive Achilles irritation or calf fatigue.

The plate in the forefoot is not overly aggressive as there is still plenty of flexibility at the toes. However it engages based on your pace. When I am running easier, the plate lets me flow through the forefoot. When the pace picks up, I can feel it engage more. Durability wise the lugs are handling my hard impacts very well. I have next to no wear on the outsole, which is fairly normal for Newton shoes. Thus I would expect an above average number of miles out of these. For those who like Newton or low drop shoes and want a lightweight trainer than can handle training miles, workouts and races, this may be one to check out. 

David: I'll be honest, the Gravity 10 did not work for me but.... the Gravity + did. I really enjoyed this model. The ride still rides a little on the firm side like most Newtons but the midsole density was just soft enough to not feel like I was running "on" the lugs and actually using them. Newton normally uses a system they refer to as ART, Action-Reaction Technology, using the forefoot lugs and a membrane underneath to compress and provide a more fluid and responsive toe off. In some models this system has been a little hit and miss for me but it feels pretty dialed in on the Gravity +. The shoe has a 3 mm drop that is leveled with the lugs up front. The feeling is almost like a balanced 0 drop shoe that you just roll off of the front with. The lugs don't feel overly aggressive in the Gravity +. I have multiple double digit mileage runs in them and they have been comfortable. I did need to break them in a little bit and get used to walking in them first before running in them but once they broke in they were great. One thing I do notice with the lower stack height and ART design is it feels that my cadence is a little on the quicker end than if I am running in a little more of a traditional shoe. The design feels pretty nimble up front like I am in a lightweight racing flat but still reeled in enough to run daily miles in it. When running fast the shoe feels smooth through the forefoot with a nice fluid toe off. Don't get me wrong, you can certainly feel the lugs, but the integration is done well on this model from everything I have put it through so far. For me, this is my favorite Newton.

Andrea: Like many shoes, the ride of the Gravity+ is different at different speeds. At easier paces, the lugs are noticeable, but in a way that increases your proprioception, not in a negative way. I felt more connected to my feet when running in these shoes as compared to other lower drop shoes I have tested. These shoes feel amazing at faster paces. The wider forefoot, lugs, and toe spring encourage a very smooth and fast push off, and the feeling of the lugs disappears entirely. I tested these shoes during a variety of intervals, including strides, hill repeats, and intervals at threshold, mile pace, and 400m pace sprints. These shoes are quite simply fun to go fast in. The NRG+ foam is responsive and provides just enough cushion to prevent these shoes from feeling harsh. I have done workouts as long as 10 miles in these shoes and my feet did not feel beat up or tired like they have with other lower drop shoes. This is the first pair of Newtons I have tested, and my experience with the fit and performance of the Gravity+ definitely makes me want to try other models.


Matt: Newton always does a great job on stability even in their neutral models. The Gravity + is a great example of this. Note that this is not a stability like Newton's Motion, Kismet and Distance S models as there is no post or traditional stability measures in this shoe. However, the firmer ride, good ground feel, lugs and XPS+ plate provide a mild to moderate level of stability for those who need it in the forefoot. The heel and midfoot are fairly are fairly average on stability, but the number of mechanisms and wider last in the forefoot provide a high level of guidance up front. The XPS + plate and lugs increase torsional rigidity and facilitate forward motion very well. The firmer ride and ground feel increase stimulus into joint proprioceptors in the ankle, allowing for faster responses from muscles during loading response. The stability at the forefoot is enough that it offsets the narrowed midfoot, but those who need more rearfoot/midfoot stability should look at the Kismet (REVIEW).

David: Newton has always done a pretty good job in the stability department with their shoes, especially in the forefoot region. The Gravity + is a neutral shoe and does not feature any posting or specific stability features but does have a couple things that help. The upper is dialed in and keeps the foot on the platform well. The shoe is relatively low to the ground and provides good ground feel, helping with proprioception. The forefoot lugs and rigidity up front do seem to help with some rotational stability while also unloading the great toe (might be why this model works for me). The heel and midfoot are nothing to really rave about on stability and run pretty similar to most neutral shoes. If I am being really picky, perhaps the midfoot could be a tad more stable by either widening the platform slightly or by using a sidewall with upper and midsole integration. Otherwise I'm pretty happy with it.

Andrea: The Newton Gravity+ is a neutral shoe with some non-traditional stability features. There is mild medial and lateral sole flare in the midfoot and forefoot. The firm external heel counter helps to center the heel without preventing motion. The combination of the XPS plate, lugs, and toe spring provide guidance through a smooth and natural toe off. The stiff outsole and lugs promote dynamic stability through increased foot and ankle proprioceptive input. Many runners will notice a naturally higher cadence when running in the Gravity+ due to these features.


For Every Action, by Senior Contributor David Salas
It is always interesting to look at geometry of footwear and what makes each shoe unique. With the Newton Gravity + it still uses the Action-Reaction Technology (ART) that people have come to know them by. What is new to Newton in 2021 is that they are using sustainable and eco-friendly materials. It is not often that biodegradable and responsive are in the same sentence but this shoe can certainly moved when pushed. I think a large part of that is actually the lugs up front providing a good sense of traction and ground feel for a lower profile shoe like this. The shoe feels like a racing flat when the pace picks up and the lugs do have a sensation of compression when loaded. Since you roll off of the front of the lugs, you don't necessarily feel the flex point at the great toe when running where you normally are pushing off into the early swing phases. It has been found that peak forces through the forefoot can be higher in lower stack shoes, along with decreased contact time (Ogston, 2019). With the Newton specifically it seems like the shoe tackles this phenomenon uniquely by having the membrane and lugs up front. It does seem like the pressure gets reduced a little bit in that region with an especially quick toe off since you are rolling off of the lugs. This last part is anecdotal on my part but does feel to help, especially since the midsole isn't an incredible bouncy or responsive foam standing alone.


Ogson, J.K. (2019). Comparison of in-shoe plantar loading forces between minimalist and maximalist cushion running shoes. Footwear Science, 0. 1-7. DOI: 10.1080/19424280.2018.1561760

Studies on Newton Shoes?, by Contributor Andrea Myers
When considering the features of the Gravity+, the lugs clearly stand out as the defining feature of the shoe’s unique ride. Naturally, I wondered if any research had been published regarding the design or performance metrics of Newton shoes. As is common in the running science world, there was not much to be found. Researchers at Sacred Heart University here in Connecticut published a study in 2013 that examined the influence of the lugged design of the Newton Neutral Trainer shoe on running economy in trained distance runners (Moran and Greer 2013). They tested runners wearing two types of shoes: the Newton Neutral Trainer and a modified version of the Newton Neutral Trainer that had the lugs shaved off. The subjects were 12 highly trained male distance runners who were tested in a series of runs on a treadmill. They first had all subjects complete a VO2peak test using a standard, graded treadmill protocol. The subjects were allowed to wear their usual running shoes for the test. 5-7 days later, the subjects returned for 4 stages of 2x6 minute treadmill runs at submaximal paces. The submaximal paces were individualized for each subject based on their VO2peak test result. The researchers used a protocol similar to one described by Jack Daniels in a 1992 study on running economy in elite male and female runners (Daniels and Daniels 1992). Each stage included one 6 minute test in the lugged Newton and one 6 minute test in the lugs-removed Newton separated by a 5 minute passive recovery phase. None of the subjects had previous experience running in Newtons prior to the experiment.

The researchers looked at differences in running economy between the test conditions. They found a statistically significant improvement (0.95%) in running economy during runs using the lugged shoe. They also found a statistically significant reduction in rate of perceived exertion (RPE) when running in the lugged shoe.

The researchers proposed a variety of potential explanations for their findings, including changes in lower extremity kinematics, muscle activation, and/or increased midsole energy return from the lugs. They also discussed the running economy findings for each subject: 1 saw a small decrease in running economy in the lugged shoe, 1 had no difference in running economy between shoes, and 3 saw an improvement in running economy >2% in the lugged shoe. The other subjects showed an improvement in running economy in the lugged shoe between 0.29-0.94%. This underscores the individual response to a given shoe and the trouble with generalizing research findings to a general population. This study may have had different findings if they used a greater number of subjects, included women, and/or included less highly trained runners.


Matthew F. Moran & Beau K. Greer (2013) Influence of midsole ‘actuator lugs’ on running economy in trained distance runners, Footwear Science, 5(2), 91-99, DOI: 10.1080/19424280.2013.792878

Daniels, J. and Daniels, N. 1992. Running economy of elite male and elite female runners. Medicine and Science in Sports and Exercise, 24(4): 483–489.


Matt: The Newton Gravity + is by far my favorite of all Gravity and Motion models that I have tried. My major recommendation would be to make a Motion + model. I would normally criticize the narrowed midfoot, but I understand this is a neutral uptempo model. For those that need a little more stability through the heel and midfoot, a Motion + model would be great. My other recommendation would be to emphasize the action reaction technology in the rearfoot. The forefoot is great (obviously), but most runners will spend some time on their rearfoot during a long distance run or race. If Newton can make even better use of energy return or forward motion facilitation in the rearfoot the way they do in the forefoot, the Gravity + will work for an even larger number of runners. 

David: I really enjoyed the Gravity + for my daily mileage and some uptempo work. For me this is my favorite Newton and I don't have too many recommendations for the model, however the midfoot could slightly be reworked. There is a tiny bit of instability through that region and this could be helped with either widening the platform in that region or using a sidewall with upper and midsole integration.

Andrea: I really enjoyed running in the Gravity+. For me, I wouldn’t change a thing about the shoe - it fit and performed that well for me. The main limitation of the Gravity+ is that it is a 3mm drop shoe that will perform like a 0mm drop shoe for heel strikers. Heel strikers or those who are not accustomed to running in lower drop shoes will need to ease carefully into the Gravity+ to avoid injury.


Matt: The Newton Gravity + is a lightweight trainer/long distance racer for those that want a responsive, low drop shoe. The Gravity + is nimble and responsive enough for workouts, but durable, protective and tough enough to handle training miles for those used to shoes like this. The 3mm drop is noticeable, but the XPS+ plate and NRG+ foam are more forgiving and don't make this Newton shoe feel negative drop. Like the Kismet and Fate, two introductory shoes by Newton, the Newton Gravity + may serve as a great introductory low to zero drop shoe for those interested, but we still suggest slowly transitioning into it. As fast and as fun as this shoe is, the body needs time to adapt.

David: The Newton Gravity + is a lightweight versatile trainer/racer that will work well for those that like a lot of ground feel and a sense of nimbleness on foot. The shoe is a relatively firm riding throughout and does feature a pretty low drop ratio at 3mm, but protective enough for daily mileage. The shoe felt like it helped my legs maintain a high cadence on foot with quick transitions throughout, especially through the forefoot. Because Newton does feature forefoot lugs, it would be advised to break the shoes in first and get used to the feel of the shoes if you have never worn Newtons before.

Andrea: The Newton Gravity+ is a neutral, 3mm drop shoe that has a unique and fun ride at fast paces. It provides a firm and responsive ride that will encourage a higher cadence and smooth toe off. Runners who are not currently using low drop shoes should progress slowly into the Gravity+ to avoid injury. If you are looking for a lightweight, low drop shoe for your interval days or races, the Gravity+ will be an excellent option.


Fit: A (Extremely comfortable and secure upper. High breathability and comfort against bare skin)
B+ (Fun for track and road workouts. Able to do more distance for those not used to Newton, but still on the firmer end)
Stability: B+ (Excellent stability through the forefoot. Midfoot a bit narrow and heel average stability)
DPT/Footwear Science: B+ (Excellent redesign that is eco-friendly while still being an high level performance shoe. Great stability and direction through the forefoot. I would like to see the same thing applied in the rearfoot)
Personal:  B+ (One of my favorite uppers and a shoe I keep reaching for during track striders and shorter runs. Low drop is still something that I personally need to acclimate more to before reaching for this shoe more)
Overall: B+ (Impressive Eco-Friendly and performance shoe for those wanting a trainer/racer combo in a lower drop shoe with one of the most comfortable uppers I have experienced).

Fit: (Very dialed in upper, sock like but still supportive, breathable but still protective, very comfortable throughout)
A- (Still runs a little on the firmer end, but nimble, lightweight, and responsive for everything I need it for)
Stability: B+ (Good forefoot stability, good upper, nothing major in heel, midfoot slightly unstable but otherwise good)
DPT/Footwear Science: A- (Biodegradable and eco-friendly don't usually go in the same sentence with responsive and fun, overall good design for what they are working with)
Personal:  B+ (A really fun shoe to run in, though I may actually reach for some other daily trainers over it, aesthetics and lifestyle game is killer though and I have received many compliments on these shoes. Good do it all shoe.)
Overall: B+/A- (Responsive and fun ride for an eco-friendly shoe, great upper, still a little firm riding with a tiny bit of midfoot instability)

Fit: A (wide toe box, unintrusive heel counter, breathable mesh upper, secure lockdown)
Performance: A- (fun to run fast in this shoe. A great interval or race day option. Can be used for daily miles, but not the best use for the shoe due to firmness)
Stability: B+ (nice non-traditional stability features for a neutral shoe)
DPT/Footwear Science: A- (forefoot lugs may promote improved running economy for some runners based on limited evidence, corresponds with my anecdotal experience)
Personal: A (loved doing intervals in this shoe and will keep it in my fast day rotation)
Overall: A- (great fit and performance, excellent sustainability features)


Find the Newton Gravity+ at Running Warehouse here. Using the link to purchase helps support Doctors of Running. Thanks so much!

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r. Matthew Klein
is a 150 lb male with notable PRs of 14:45 for 5k and 2:32:44 for the full marathon.  He typically runs 70-100 miles per week and trains at a variety of paces from 8min per mile recovery runs to 4:40 per mile 1k repeats.  He prefers firmer and responsive shoes with snug heels and medium to wide toe boxes.  The stability guy of the group, he also prefers a little stability in his footwear. However, as a researcher, clinician and running shoe aficionado, he will run in anything.

Dr. David Salas is a 135 lb male with notable PRs ranging from 3:54 in the 1500m to 1:08:36 for half marathon. He typically runs 60 to 70 miles per week and trains from about 7:30 recovery runs to fast shorter efforts at 4:30 pace. He normally prefers neutral shoes with a firmer ride, but is completely open to other types of shoes.  He is a footwear enthusiast at heart and will always appreciate a high quality shoe when it comes around. For updates on training or testing, 

Dr. Andrea Myers is a 5’7”, 130 pound female with PRs of 3:04:48 for the marathon and 18:41 for the 5k. She typically runs 35-60 miles per week with recovery runs at 8:00-8:30/mi pace and 5:30/mi pace for shorter efforts. She prefers firmer, neutral shoes with 4-8mm of drop and high volume toe boxes.

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 Newton Running 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 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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NEXT:  Saucony Endorphin Pro+ Discussion, Orthotics, and Role of Higher Drop Shoes | EP 58

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