Carbon-Plated Shoes Still Boost Running Economy After 90 Minutes - Here’s the Fine Print | Find Your Stride | Edinburgh Podiatrist

Background: The Rise of “Super Shoes”

Since the debut of carbon-plated running shoes in 2016, nearly every marathon record has fallen. These Advanced Footwear Technologies (AFTs) — think Nike Vaporfly and Alphafly — combine lightweight PEBA foam, carbon plates, and rocker geometry to improve running economy (RE), or how efficiently a runner uses oxygen at a given speed.

While short-term benefits (2–4% improved efficiency) are well-documented, researchers have questioned whether these gains last through longer races. That’s where the new study by Schwalm et al. (2025) comes in.

'Super shoes' such as the Nike Vaporfly and Alphafly combine lightweight PEBA foam, carbon plates, and rocker geometry to improve running economy.

Study Overview

Paper title: Running Economy Benefits of Advanced Footwear Technologies Remain Over a Prolonged Run in Highly Trained Distance Runners

Authors: Lars C. Schwalm et al., MSH Medical School Hamburg

Journal: Medicine & Science in Sports & Exercise (Accepted July 2025)

Design

• Participants: 9 elite runners (5 female, avg age 32)

• Shoe conditions:

  • AFT – Nike Air Zoom Alphafly Next% 2

  • Non-AFT – Brooks Launch 10 (no carbon plate or PEBA foam)

• Protocol: Two 90-minute treadmill runs at sub-threshold pace (randomised crossover)

• Measured: Energetic cost of transport (ECOT), oxygen consumption (VO₂), biomechanics, lactate, HR, RPE

Key Findings

Running Economy Improves and Stays Improved

• RE was ~3.2% better in AFTs throughout the 90-minute run.

• The advantage did not fade over time, even as fatigue set in.

• However, both shoe conditions showed a similar 5–6% deterioration in RE over the run — meaning AFTs help you start more efficiently but not resist fatigue any longer.

Biomechanical Shifts Are Temporary

• At the start, AFTs reduced contact time and step rate, while increasing flight time — consistent with prior research on propulsion benefits.

• As fatigue accumulated, biomechanical differences faded, suggesting runners naturally revert toward their baseline gait patterns.

  
  

Physiological Markers Support Efficiency

• Heart rate and perceived exertion were slightly lower in AFTs.

• Respiratory exchange ratio dropped, indicating greater fat oxidation efficiency in AFTs.

Critical Analysis: What This Means for Podiatrists and Athlete Performance

Strengths

✅ Ecologically valid duration: A 90-minute test better represents half-marathon and marathon conditions than prior short trials.

✅ Comprehensive biomechanical analysis: The study used high-speed 3D motion capture and integrated pressure plates for detailed stride metrics.

✅ Controlled comparison: Traditional lightweight shoes offered a fair control without plate or advanced foam bias.

Limitations

⚠️ Small, elite sample (n=9): These results may not apply to recreational runners with different gait or foot strike patterns.

⚠️ No habituation period: Participants ran in brand-new shoes, so adaptation effects were not measured.

⚠️ Treadmill testing: Real-world terrain variability and fatigue response could differ outdoors.

⚠️ Single AFT model: Findings may vary across shoe brands and plate designs.

Biomechanics and Podiatry Implications

For podiatrists, this study reinforces that AFTs alter loading and gait mechanics, but these changes may not persist under fatigue. Clinically relevant takeaways include:

• Reduced ankle range of motion in AFTs may shift load distribution proximally (toward knees and hips).

• Potential implications for Achilles and calf management, particularly in runners with limited ankle mobility.

• Custom orthotic fit: The rocker midsole and carbon stiffness may affect orthotic function

• Individual variability: Not all runners benefit equally; some may perform better in traditional trainers.

Bottom Line: Super Shoes Help — But They Don’t Defy Fatigue

AFTs offer a clear metabolic efficiency boost (~3%) that holds steady during long runs, but they don’t slow the inevitable fatigue-related decline in running economy.

For runners, that means super shoes help you start faster or sustain pace with less energy cost — but the gains won’t increase as you go.

For podiatrists and coaches, it underscores the importance of personalised footwear recommendations and long-term adaptation when prescribing AFTs.

“Advanced footwear reduces the energy cost of running — but durability of efficiency depends on the runner, not just the shoe.”

Citation

Schwalm, L.C., Fohrmann, D., Schaffarczyk, M., Herrmann, A., Gronwald, T., & Hollander, K. (2025). Running Economy Benefits of Advanced Footwear Technologies Remain Over a Prolonged Run in Highly Trained Distance Runners. Medicine & Science in Sports & Exercise. DOI: 10.1249/MSS.0000000000003823

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