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Newton CF1 Carbon Racer Review
By Andrea Myers and Matthew Klein

The Newton CF1 Carbon Racer is Newton's entry into the super shoe market. With a PEBA midsole, carbon plate, and Newton's Action Reaction Technology, the shoe has been long awaited by Newton fans. The shoe features Newton's newest foam, Newtonium-P, is certified vegan, and sustainably constructed. Our team has loved the fit and performance of previous Newton shoes, and we were all excited to test the CF1 Carbon Racer.

Newton CF1 Carbon Racer
Price: $230 at Newton
Weight: 8.5 oz, 241 g (men's size 9/women's size 10.5)
Stack Height: 34 mm / 30 mm
Drop: 4 mm
Shoe Purpose:

Pros: Comfortable upper, snappy ride
Cons: Very heavy for a racing shoe, expensive for its weight


The Newton CF1 Carbon Racer is Newton's first super shoe. It features a forked carbon plated sandwiched between two layers of Newtonium-P, which is a PEBA foam. Being a Newton, it also features forefoot lugs (Action Reaction Technology), which do not feel as prominent as other models of Newton shoes. At 8.5oz for a men's 9, it is on the heavy side for a super shoe, particularly considering it has a lower stack height at 34mm/30mm. Due to its weight, this shoe might best function as a performance trainer or ultra distance racer for runners who prefer the performance of Newton's Action Reaction Technology and classic Newton fit.

: Salomon S-Lab Spectur, New Balance SC Elite v4

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

Matt: The Newton CF1 Carbon Racer fits me true to size if slightly short in my normal men's US size 10. The overall fit is slightly snug which is different than most of the Newtons I have tried. The volume is normal to slightly lower but there is some mild stretch to the upper. The forefoot is snug with a tapered toe box that did break in with time. this transitions into a normal to slightly snug midfoot. The tongue is thin and gusseted. The security was good as I did not have to lace lock the shoe at all or tighten the laces much. This transitions into a normal to slightly snug heel. There is a moderately stiff counter in the rearfoot with a small amount of heel collar padding. The counter only comes up part way which makes it less aggressive. Those sensitive to counters may not do well but I did not have too much of an issue. Sockless running is fine for the most part in this shoe outside of the tapered toe box and mild toeguard. Those used to running sockless in Newtons should be fine for short-to-moderate distances but I would use socks for anything longer. 

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

Andrea: Newton recommends going up 1/2 size in the CF2, so I received a women's 10/men's 8.5 (unisex sizing) instead of my usual 9.5. This was definitely the right choice, as I had a full thumb's width from the front of my big toe to the end of the shoe. I would have found the 9.5 too short. The toe box has enough width that I did not experience any irritation at my 1st or 5th MTPs, and the width of the midfoot and rearfoot are normal. I did not have any issues achieving comfortable lockdown with the laces and the serrated laces stayed tied without any issues. The gusseted tongue is additionally secured by a lace loop. The tongue is relatively thin, but has just enough padding that I did not experience any irritation on the dorsum of my foot from the laces. There is a rigid heel counter in the lower half of the rearfoot and a small amount of padding internally. I found the fit and hold of the rearfoot to be comfortable and did not experience any chafing or blisters. I have almost always liked the fit of Newton shoes and I found the fit of the CF1 to be similarly well done.

Andrea's Typical Size: Women's US Size 9.5
Shoes that have fit Andrea well: New Balance Beacon v3, Brooks Hyperion Max, Topo Cyclone 2, Nike Vaporfly 3, Altra Via Olympus 2
Shoes that have fit snug: Saucony Kinvara 14 (length and toe box width), Altra FWD Experience (length and width), Hoka Cielo Road (toe box width), Saucony Endorphin Speed and Pro 1-3 (length)
Shoes that have fit large: Adidas Boston 12 (length), Adidas Adios 8 (length)

Doctors of Running Checklist

Is This a Good Shoe for Walking: No
Is This a Good Shoe for Standing: No
Is the Forefoot Flexible: No
How Flexible is the Shoe: Not Flexible
Is This a Good Heel Bevel: Yes
Recommended for Haglunds: No
Recommended for Sockless: No
Durability Expectation: Average


Matt: The Newton CF1 Carbon Racer is more of a Super Trainer than a Super Racer. It is best described as a highly cushioned Newton that feels better going longer at slower paces than shorter at faster paces. The midsole is clearly a soft PEBA foam (Newtonium-P) that feels soft and compliant underfoot. The heel/midfoot are soft and transition into a mildly soft forefoot. The lugs are still noticeable in this Newton shoe but at are far muted compared to others. Those sensitive to the lugs will do much better in this shoe. There is a 4mm heel drop and that is what this shoe feels like. As I fatigue and land harder at the heel, the heel drop feels lower due to the more compressive foam. The heel transition is smooth thanks to a large bevel and the soft foam. This transitions into a soft midfoot and the forefoot lugs. The lugs still pivot you over them and make for a somewhat snappy toe off. The softer foams slows this down a bit, making this shoe feel best at easy and uptempo paces. I have used this shoe mostly for easy and long runs, where it has felt best. I have attempted to do several fartlek and track workouts that have been absolute struggles.

Unlike other Newtons, the midsole material is softer and the shoe does not respond well to fast paces. Uptempo paces are fine, particularly over longer efforts but anything faster feels like I am fighting with the shoe. The slightly higher weight for a "racing shoe" also adds to this, which further makes this shoe feel like a super trainer. It has felt comfortable over longer efforts and I could see those doing road ultra marathons liking this shoe. Since I focus on shorter distances, this will not be a shoe I choose to race in.

Surface-wise, the Newton CF1 Carbon Racer is best only for road. The smooth outsole and exposed PEBA foam is at risk for high wear with uneven/aggressive terrain. The traction is also only average with a mild exception for the forefoot because of the lugs. The durability is also average, so will be best for smooth surfaces. I have over 30 miles on my pair and am beginning to see wear on the rearfoot outsole. I have not worn through it, but see it lasting a normal amount for a lightweight training shoe. Those who land farther forward and utilize the lugs for both landing and toe-off may have a different experience.

The Newton CF1 performed more like a heavier supertrainer as opposed to a true racing shoe for me. I enjoyed my first test run in it, which was 6 miles at easy pace. The shoe felt snappy and I could feel the forefoot lugs engage a little to propel me into push off, which made me think the shoe would feel even better at faster paces. My second run in the shoe was a workout with LT intervals. While the shoe definitely felt more responsive at the faster pace, I was acutely aware of the weight of the shoe. 8.5oz for a men's 9 (and I am testing a men's 8.5) is unreasonably heavy for a shoe with a 34mm/30mm stack height and PEBA midsole. I felt like I was back on the swim team, wearing an extra suit to increase drag for a tougher workout. The shoe does respond well to load and the lugs definitely came alive at LT pace, but I just couldn't get past how heavy the shoe felt. My next run in the shoe was a longer easy run, which was more enjoyable because at a slower pace, I could enjoy the comfortable underfoot protection and snappy ride of the PEBA midsole, plate, and forefoot lugs. My long runs are 10-14 miles right now because I am not in marathon training, but I could see the CF1 performing well for 16+ mile runs ranging from easy to marathon pace. I absolutely would not race in the shoe due to its weight, but perhaps it would work well for ultra distance races at slower paces.

The shoe does feel like its stated 4mm drop and because the forefoot lugs are not as prominent as other Newton models (like the Fate or Distance lines), the lugs do not turn the shoe into one that feels like a zero drop shoe. I found it comfortable for midfoot landings at all paces and felt like the lugs and forefoot rocker lined up with my MTPs appropriately. I also liked the high longitudinal bending stiffness of the shoe and the firmer ride. Traction was average in the shoe and I definitely would not choose it for a rainy run because the lugs were a little slippery on wet roads. I have 25 miles on my pair and there is almost no visible wear, even on the small section of exposed midsole in the midfoot. 

(Learn more about stability in our full guide)

Matt: The Newton CF1 is a neutral shoe with some guidance features in the forefoot. The heel and midfoot are mostly neutral although feature some mild sidewalls on each side of the foot. These are made of the same soft Newtoniun-P material, so they compress easily. The midfoot is not as stable due to the medial cut out despite the taller platform. The full length forked carbon fiber plate does add torsional rigidity in the midfoot/heel, but this appears to balance out the softer midsole foam rather than add more stability above normal levels. The forefoot is wider with sole flare from both the platform and lugs. The forking and spread of the plate also creates noticeable torsional rigidity up front. Combined with the lug system, this creates a forward-guided feel in the forefoot. Those with mild stability needs will do fine at the forefoot while those with neutral needs in the midfoot and heel will do best. 

The Newton CF1 is a neutral shoe with some well done guidance features. Newton is most well-known for their forefoot lugs, which they call Action-Reaction Technology. The lugs definitely perform differently across Newton models, with some models really only feeling comfortable at faster paces, which results in proper loading of the lugs. The lugs in the CF1 appear to be less prominent than other models I have tested (Fate and Distance+) and this results in the shoe feeling comfortable at a variety of paces, although faster paces do seem to "activate" the lugs better with increased loading. The very stiff platform and well designed heel bevel and forefoot rocker provide smooth guidance from initial contact to push off, including for midfoot landings. The stiff platform and rocker geometry also may reduce stress on the MTPs and calf muscles, but place increased stress on the hip at terminal stance. There is also well balanced sole flare medially and laterally in the forefoot, which feels like it helps to center the foot as I progressed to push off. 

Thoughts as a DPT: Shoe Weight and Performance
By Andrea Myers
Shoe weight is one of the most important features of a racing shoe. Many studies have found that running economy worsens when shoe weight increases. A well known study by Hoogkamer et al in 2016 found that running economy decreases by 1% per 100g added to a shoe (100g = 3.52oz). Another study by Rodrigo-Carranza et al in 2020 found similar results, but also emphasized that the effect of shoe mass is more pronounced at speeds associated with VO2 max as compared to submaximal intensities. A systematic review published in 2014 by Fuller et al found a significant positive association between shoe mass and running economy. The authors concluded that "shoe mass is a critical consideration for designing and selecting shoes for use in distance running competition." The body of evidence for using lightweight shoes for racing is supported by extensive evidence and is also intuitive. With this body of evidence, it is surprising that in 2024 a shoe company would market an 8.5oz shoe as a racing shoe. The presence of a PEBA-based foam and carbon plate is not enough to make a good racing shoe. The shoe also needs to be lightweight and perform at race paces. Shoe R&D has progressed to the point that nearly every company has a designated racing shoe with PEBA or supercritical foam and a carbon plate. Runners should know that the presence of these features does not guarantee the shoe will be a good racing shoe. The number one factor a runner should consider for a distance racing shoe is comfort, followed by shoe weight. 


Hoogkamer, W., Kipp, S., Spiering, B. A., & Kram, R. (2016). Altered running economy directly translates to altered distance-running performance. Med Sci Sports Exerc, 48(11), 2175-80.

Rodrigo-Carranza, V., González-Mohíno, F., Santos-Concejero, J., & González-Ravé, J. M. (2020). Influence of Shoe Mass on Performance and Running Economy in Trained Runners. Frontiers in physiology, 11, 573660. 

Fuller, J. T., Bellenger, C. R., Thewlis, D., Tsiros, M. D., & Buckley, J. D. (2015). The effect of footwear on running performance and running economy in distance runners. Sports medicine (Auckland, N.Z.), 45(3), 411–422. 


Matt: While I have enjoyed running easy in the CF1, this is not a shoe I would buy to race in. It feels too drastically different from most Newtons and I would choose other shoes in their line up long before I chose this to race fast in. If Newton is shooting for an ultra distance racer, then I could possibly see where they were going. However, this feels as if it has strayed too much from Newton. My first suggestion would be to get the weight down to a true racing weight. 8.5 ounces and the compliance of the sole feels more like a Super Trainer than a racing shoe, so getting that down into the sub 8 oz range should be a focus given almost all their other shoes are in that range. While I applaud the use of a new PEBA foam, it feels more compliant than responsive. This makes it feels better for training, which is not what the name of this shoe suggests. I would suggest increasing the resilience of the foam to better match the faster forefoot transition Newton is known for. Finally, I would go back to the design of other Newtons and widen the forefoot fit. If the goal is to use those lugs to facilitate a great forefoot transition (regardless of footstrike) the goal should be to allow appropriate spread of the toes for normal foot motion. The taper of this shoe feels so different than the Gravity/Motion/Kismet etc that those wanting that solid forefoot shape will walk away disappointed. I applaud the first attempt but version two needs a major overhaul sticking more closely to Newton's principles.

Andrea: I enjoy running in Newtons and was excited to test their first super shoe. I love the fit and snappy ride of the CF1, but the weight is almost unacceptable for a super shoe in 2024. There are a number of non-PEBA based daily trainers with similar stack height that weigh less than the 8.5oz CF1. Newton needs to figure out how to shave an ounce off the shoe for it to be remotely comparable to other shoes on the market, especially at $230. 


Matt: The Newton CF1 Carbon Racer is for those who want a longer distance racing shoe that does best at easier to uptempo paces. Those with a more narrow foot or wanting a snug fit will do best in this shoe. The ride is a more cushioned version of the Newton lug system and feels best at uptempo or easier paces over longer distances. This shoe is especially great for long runs, particularly for those wanting a lower-drop "super" shoe. However, this is more of a super trainer or super shoe for marathon and longer distances. Right now, it has a confusing place in the Newton line up as their "racing shoe" is heavier than the majority of their other shoes. While this shoe may do well on the road ultra scene, some additional work needs to be done for it to be competitive with other current super racing shoes on the market at its price point. 

Andrea: It would be hard for me to recommend this shoe based on its high price and weight. There are many other shoes that are lighter and perform just as well or better at a variety of paces. I think the CF1 is going to be a niche shoe for runners who love other Newton models and prefer to stick with the brand. Its weight will limit its utility in races to marathon distance or longer. For those looking for a long run shoe with a firm midsole, rocker geometry, and get along well with Newton lugs, this could be a nice option. I hope Version 2 has similar ride but loses some weight to make it more comparable to other super shoes on the market.


Fit: (I did not go a half size up. Felt secure but slightly snug/tapered)
Performance: B-
 (A super trainer that feels best at easy and uptempo paces. No versatility into faster efforts. Best for ultramarathon and long run type distances).
Stability: B [Neutral] (Guided forefoot with lugs and stiff plate but narrowed midfoot and softer foam makes for neutral heel/midfoot)
Value: C (Not a racer. Other Newtons are way faster. Should be priced as a super trainer at $180)
Personal: B-/B (A solid shoe for longer efforts but not something I can use for anything fast and would not use it as a racing shoe)
Overall Design: B- 

Fit: (Great Newton upper and fit, comfortable toe box, easy to lockdown laces. Newton recommends going 1/2 size up.)
Performance: C+ 
(Feels comfortable at easy paces, but is too heavy for me to use even as a performance trainer. Comfortable on longer easy runs, but definitely not one of my top picks.)
Stability: [neutral] B (Nice guidance elements for a super shoe, high longitudinal bending stiffness and rocker geometry contribute to snappy ride.)
Value: C (High weight makes the $230 price tag quite unjustified.)
Personal: C (While I love the fit, the CF1 is way too heavy for racing and workouts.)
Overall Design: C+ 


Newton CF1 Carbon Racer
Price: $230 at Newton Running

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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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