06/16/2025
Fast-R Nitro Elite 3 and Running Economy
By Andrea Myers
From our review of the new Fast-R: https://www.doctorsofrunning.com/2025/06/puma-fast-r-nitro-elite-3-review-2025.html
If you have read anything about the Puma Fast-R Nitro Elite 3, you have probably seen that Puma states it has 3.15% improved running economy as compared to the Fast-R Nitro Elite 2. This data comes from a pre-print article (which means it has not been through the peer review process yet) in which researchers including Dr. Wouter Hoogkamer, previous DOR podcast guest and author of many articles on super shoes and running performance, and Laura Healey, also a previous podcast guest and Senior Manager of Research and Sport Science at Puma.
In the study on the Fast-R Nitro Elite 3, Dr. Hoogkamer and his colleagues compared the Fast-R Nitro Elite 3 with three other shoes: the Puma Fast-R Nitro Elite 2, Nike Alphafly 3, and Adidas Adios Pro Evo. The subjects were 15 trained runners who were all accustomed to running in super shoes. They were 11 males, all of whom have run a 5k under 19:00, and 4 females, all of whom have run a 5k in under 21:00. The test protocol involved running on an instrumented treadmill in each of the four shoe models twice, with 5 minutes of running and 5 minutes of rest. The test speeds for the subjects were based on recent 5k results and experience and included 8 male subjects running at 16 km/h (9.94mph), 3 male and 3 female subjects running at 14 km/h (8.69mph), and 1 female at 12.9km/h (8.01mph). These speeds convert to 6:02 min/mi, 6:54 min/mi, and 7:29 min/mi respectively. Running economy was measured as average metabolic rate in W/kg, based on the rates of oxygen uptake and carbon dioxide production. The results of the study found that the Fast-R Nitro Elite 3 resulted in improved running economy compared to all three shoes, for all subjects. There was a 3.15 +/- 1.24% improvement compared to the Fast-R Nitro Elite 2, 3.62 +/- 1.25% improvement compared to the Alphafly 3, and 3.54 +/- 1.16% improvement compared to the Adidas Adios Pro.
The authors state that the most notable result from this study is that every subject demonstrated their best running economy in the Fast-R Nitro Elite 3. This is different from previous studies that compare subjects' running economy in different super shoes, in that differences in running economy when comparing two super shoes (or shoes with advanced footwear technology/AFT as defined in the article) are normally smaller and not consistent between subjects. The authors state that the reason the Fast-R Nitro Elite 3 performs so much better is that it was designed with "data-driven computational design analysis." Puma is not unique in using computational design analysis in the shoe development process, so it will be interesting to learn more about the specific design parameters Puma used and why they may be the reason that the Fast-R 3 performed better than the Alphafly 3 and Adios Pro Evo. The improved performance over the Fast-R 2 includes a significant reduction in shoe weight (249g vs 167g). The authors stated that the difference in weight accounts for 0.8% better running economy between version 2 and 3, and that the remaining 2.3% improvement can be attributed to the improvements in plate geometry and stiffness as well as midsole energy storage and return. Interestingly, the authors stated the in their testing, the Fast-R 3 had the lowest compression stiffness, the lowest bending stiffness, and the highest percent energy return as compared to the three other test shoes. They attribute the improvement in running economy to the interaction of these factors.
When reading a research study involving humans, it is important to understand its limitations. This study had a small sample size that involved runners who are faster than the average runner, but no elite (marathon pace faster than 18km/h) or recreational runners (marathon pace slower than 12km/h). There were only four female runners and all subjects were in their mid 20s to late 30s. The male subjects' weights were 67.5 +/- 4.5kg and the female subjects' weights were 59.1 +/- 2.2kg. If you are of a similar age, weight, and marathon pace to these subjects, then these results may be applicable to you. If your characteristics are significantly different than the subjects, the results may not apply to you as well.
References:
Kusmeski, J., Bertschy, M., Healy, L., Barrons, Z., & Hooghamer, W. (2025). Data driven shoe design improves running economy beyond state-of-the-art Advanced Footwear Technology running shoes. BioRxiv 2025. https://doi.org/10.1101/2025.04.13.648601
