Runners are often looking for an “edge”—something that will help them run faster or longer with less effort.
From training modifications to innovations in fueling and hydration products, there are various ways to optimize human physiology to perform better.
Another avenue for performance improvements is through technological innovations, namely by improving running shoes. The lighter the shoe, for instance, the lower the energy cost is associated with running at a given speed.
Carbon fiber running shoes are one of the latest innovations in training shoes. These shoes have a carbon fiber plate in the midsole and are claimed to improve running economy by at least 4%.
However, because these carbon fiber running shoes come with quite a hefty price tag, many runners are wondering if they’re worth the hype or should be reserved for the upper echelon of runners vying to break records.
Let’s take a look at the science behind carbon fiber running shoes and whether they’re worth the buy.
What Exactly Are Carbon Fiber Running Shoes?
Carbon fiber running shoes are a category of performance-focused models featuring a thin, rigid carbon fiber plate embedded in the midsole.
This plate sits between layers of foam—typically high-performance, lightweight foam—and helps increase propulsion and improve running efficiency.
As your foot strikes the ground, the foam compresses and stores energy, while the carbon plate helps stabilize the shoe and creates a lever-like effect that helps push you forward during toe-off.
The combination of the carbon plate and responsive foam is what gives these shoes their distinctive feel. The foam provides cushioning and energy return, while the plate helps direct that energy in a more efficient forward motion, reducing energy loss and improving running economy.
In simple terms, carbon fiber shoes are designed to help you run faster with less effort, which is why they’re commonly used for races—from the 5K all the way up to the marathon.
However, they’re not just “fast shoes”—they also tend to alter your stride mechanics slightly and place different demands on your muscles, which is why many runners use them strategically for workouts and race day rather than everyday training.
History of Carbon Fiber Running Shoes
The Nike Breaking2 Project was a quest to see how fast a human could run a marathon (with the goal of breaking the 2-hour barrier) if every little aspect was optimized for success.
One of the key components of this experiment was crafting the fastest running shoes.
And while the three runners designated for the project, believing they had the best shot at breaking the seemingly impossible barrier, toiled away with their training, Nike shoe designers got to work on developing the most efficient running shoe.
On May 6th, 2017, in Monza, Italy, when Eliud Kipchoge nearly broke the 2:00 barrier for a full marathon, he was wearing prototypes of the now infamous Nike Vaporfly shoes.
What was special about these shoes? They had a thin carbon fiber plate in the midsole.
When Kipchoge eventually ran the incredible time of 1:59:40 in Vienna, Austria, on October 12, 2019, the Nike Vaporfly was publicly released for its worldwide debut.
Since then, nearly every major running shoe company has a carbon fiber shoe in its lineup.
Interestingly, though we tend to think of the Nike Breaking2 Project and the Nike Vaporfly as the genesis of carbon fiber running shoes, the concept of adding plates to the midsole of athletic shoes actually dates back to the early 2000s, when research demonstrated that doing so increased the shoe’s longitudinal bending stiffness.
This made the shoe harder to bend, resulting in a higher vertical jump height.1Europe PMC. (2016). Europe PMC. Europepmc.org. https://europepmc.org/article/MED/10694134
Several years later, it was observed that up to a certain point, stiffer running shoes could also improve running economy, but this was long before the Breaking2 Project.
Do Carbon Fiber Running Shoes Make You Faster?
An article in Sports Medicine from January 2021 noted that at that time, every single women’s and men’s world record from 5 km to the marathon had been broken since the introduction of carbon fiber running shoes in 2016 by athletes wearing running shoes with plates.2Muniz-Pardos, B., Sutehall, S., Angeloudis, K., Guppy, F. M., Bosch, A., & Pitsiladis, Y. (2021). Recent Improvements in Marathon Run Times Are Likely Technological, Not Physiological. Sports Medicine, 51(3), 371–378. https://doi.org/10.1007/s40279-020-01420-7
The authors argue that these incremental performance improvements are indeed a product of technological advances in running shoe technology—namely, carbon fiber plates—rather than of actual physiological gains from changes in training methodology.
Carbon fiber plates increase the elastic properties of the shoe, which reduces the energy cost of running.
For example, the Nike Vaporfly was found to increase running economy by more than 4%.
Even independent studies have confirmed that this seminal carbon fiber running shoe improves running economy by 3-4.2% over standard track spikes, depending on the specific head-to-head comparison.3Barnes, K. R., & Kilding, A. E. (2018). A Randomized Crossover Study Investigating the Running Economy of Highly-Trained Male and Female Distance Runners in Marathon Racing Shoes versus Track Spikes. Sports Medicine, 49(2), 331–342. https://doi.org/10.1007/s40279-018-1012-3
For example, the Nike Vaporfly improved running economy by 4.2 % compared with the Adidas Adizero Adios 3, and still by 2.9% when matched in weight with the Adidas Adizero Adios 3.
Another study demonstrated a more than 4% increase in running economy when wearing carbon fiber running shoes.4Hoogkamer, W., Kipp, S., Frank, J. H., Farina, E. M., Luo, G., & Kram, R. (2017). A Comparison of the Energetic Cost of Running in Marathon Racing Shoes. Sports Medicine, 48(4), 1009–1019. https://doi.org/10.1007/s40279-017-0811-2
Practically, this improvement is said to correspond to at least a 2% improvement in performance time.5Guinness, J., Bhattacharya, D., Chen, J., Chen, M., & Loh, A. (2020). An Observational Study of the Effect of Nike Vaporfly Shoes on Marathon Performance. ArXiv:2002.06105 [Stat]. https://arxiv.org/abs/2002.06105
While this may not sound like much, it can actually be pretty significant.
Running Level has data for the average race finish times across all ages and genders for different distances. If we take those times and then apply a 2% improvement in finish time, reflected by theoretically wearing carbon fiber running shoes, we see the following changes:
| Distance | Average Finish Time | Time Savings With 2% Improvement | Finish Time With a 2% Improvement |
| 5k | 23:58 | 0:29 | 23:29 |
| 10k | 49:43 | 1:00 | 48:43 |
| Half Marathon | 1:50:15 | 3:24 | 1:46:51 |
| Marathon | 3:48:20 | 4:34 | 3:43:46 |
Ready to find your next pair? Browse our expert-tested roundups: best carbon plate running shoes, best running shoes overall, best marathon running shoes, best daily running shoes, and best running shoes for workouts.
How Do Carbon Fiber Running Shoes Improve Running Economy?
Running economy is essentially a measure of how efficiently you can run at a given submaximal pace. In other words, it is the amount of oxygen your body needs to sustain your submaximal workload.
Studies have demonstrated that running in shoes with a carbon fiber plate alters running mechanics, thereby improving running economy.
For example, one study found that ground contact time, stride length, plantar flexion velocity, and center of mass vertical oscillation were significantly different when wearing carbon fiber running shoes compared to standard trainers.6Hunter, I., McLeod, A., Valentine, D., Low, T., Ward, J., & Hager, R. (2019). Running economy, mechanics, and marathon racing shoes. Journal of Sports Sciences, 37(20), 2367–2373. https://doi.org/10.1080/02640414.2019.1633837
According to research, during walking or running, muscle contractions drive your aerobic energy expenditure.7Joyner, M. J., & Casey, D. P. (2015). Regulation of Increased Blood Flow (Hyperemia) to Muscles during Exercise: a Hierarchy of Competing Physiological Needs. Physiological Reviews, 95(2), 549–601. https://doi.org/10.1152/physrev.00035.2013
It’s thought that adding carbon fiber plates to the midsole alters the metatarsophalangeal- and ankle-joint dynamics—particularly the dynamics of the plantar flexor muscles like the gastrocnemius and the soleus.
By changing the dynamics of your calves, the carbon fiber plates lower the energy cost of running by requiring less work and, thus, less oxygen while you run relative to running in regular running shoes.
Studies show this is because the plate increases the running shoe’s 3-point bending stiffness and typically shifts the runner’s center of pressure toward the forefoot rather than the heel or midfoot.8ROY, J.-P. R., & STEFANYSHYN, D. J. (2006). Shoe Midsole Longitudinal Bending Stiffness and Running Economy, Joint Energy, and EMG. Medicine & Science in Sports & Exercise, 38(3), 562–569. https://doi.org/10.1249/01.mss.0000193562.22001.e8
Together, these altered biomechanics increase the lever (moment arm) of the foot from the ankle joint.
When the foot acts as a longer lever, you get a more powerful push-off while simultaneously requiring less of a stretch from the calf muscles (gastrocnemius and soleus).
When these muscles don’t have to generate force from a fully extended position—but rather are within more of their optimal range—they can generate more force because they’re in a biomechanically optimal position.9Fu, F., Levadnyi, I., Wang, J., Xie, Z., Fekete, G., Cai, Y., & Gu, Y. (2021). Effect of the Construction of Carbon Fiber Plate Insert to Midsole on Running Performance. Materials, 14(18), 5156. https://doi.org/10.3390/ma14185156
Moreover, the plantar flexor muscles are able to generate force much faster, which can give you more propulsive force.
Another way adding the carbon fiber plate to the midsole improves running economy is that the stiff plate limits motion at the metatarsophalangeal (MTPJ) joint, primarily at the big toe.10Stefanyshyn, D., & Fusco, C. (2004). Increased shoe bending stiffness increases sprint performance. Sports Biomechanics, 3(1), 55–66. https://doi.org/10.1080/14763140408522830
This causes a reduction in “negative work,” meaning that it saves energy from being wasted by flexing unnecessarily when you press into the ground for the toe-off part of your stride.
Because less energy is wasted, more potential energy from the joint can be harnessed into propulsive forces.
The Nike Vaporfly wasn’t the first running shoe with a carbon fiber plate, but it was the first that was significantly more effective at improving running economy.
While previous carbon fiber running shoes improved running economy by about 1%, the Nike Vaporfly improved it by 4%.
The innovations in Nike Vaporfly included the use of an extremely lightweight PEBAX foam for the midsole, which enabled Nike to significantly increase the shoe’s stack height without increasing its weight.
Note that stack height refers to how high the shoe is off the ground, so it’s essentially an indication of how much material is between your foot and the ground.
With a high stack height from the super-thick midsole, Nike had room to add a curved carbon fiber plate rather than a flat one, which further increases the plate’s effectiveness by creating a see-saw effect from heel contact to toe-off.
Coupled with the energy return from the thicker foam, the see-saw effect of the curved carbon fiber plate makes the shoe even more effective at providing energy return.
In a nutshell, running shoes with carbon fiber plates reduce the mechanical energy required to run, thereby improving running economy and performance.
The energy savings are due to three main effects of the carbon fiber plate:
- The carbon fiber plate optimizes the musculoskeletal system.
- The carbon fiber plate maximizes energy return in your stride.
- The carbon fiber plate minimizes the energy lost.
Ultimately, running in shoes with a carbon fiber plate does seem to improve running economy to some degree, depending on your speed and particular gait.
You also have to have sufficient calf strength to handle the longer effective lever arm induced by the carbon fiber plate. Otherwise, you won’t be able to capitalize on the benefits.
It’s also important to note that not all studies with carbon fiber shoes have necessarily demonstrated unequivocal improvements in running economy or performance.
One study found that carbon fiber-plated running shoes did not affect muscle activity in the soleus or calf, nor did they improve running economy compared with traditional running shoes.11Beck, O. N., Golyski, P. R., & Sawicki, G. S. (2020). Adding carbon fiber to shoe soles may not improve running economy: a muscle-level explanation. Scientific Reports, 10(1), 17154. https://doi.org/10.1038/s41598-020-74097-7
Another study comparing seven carbon fiber running shoes from top running brands found that some were not significantly better than traditional running shoes.12Joubert, D., & Jones, G. (2021). A Comparison of Running Economy Across Seven Carbon-Plated A Comparison of Running Economy Across Seven Carbon-Plated Racing Shoes Racing Shoes Repository Citation Repository Citation. https://scholarworks.sfasu.edu/cgi/viewcontent.cgi?article=1032&context=kinesiology
Only the Nike Alphafly and the Asics Metaspeed Sky were as effective at improving running economy as the Nike Vaporfly 2.
So, whether you drop the extra dough on carbon fiber running shoes is entirely up to you, but it may help you get the PR you’re chasing.
When buying running shoes, there are several important factors to consider to ensure you choose the best ones for you. Check out our running shoe guide to pick out your next perfect pair.
My own opinion is that for non elite runners the main effect of plated shoes comes from the hype and is largely psychological. If you believe it then you may gain something from it.