[Research Review] Biomechanical Analysis of the Effects of Carbon-Plate Running Shoe Bending Stiffness on Running Economy (RE): A Quantitative Biomechanics Experiment Report (No. 496)

Reference Journal Source: Journal of Biomechanics • International Research Findings Review Series

This article explores the biomechanical effects of the longitudinal bending stiffness of carbon-plate running shoes on Running Economy (RE).

How Bending Stiffness Affects Running Economy

When a carbon fiber plate is embedded in the midsole, it restricts excessive flexion of the metatarsophalangeal (MTP) joint (the joint at the base of the big toe) during the propulsion phase. Through a mechanism similar to a “lever effect,” it reduces the mechanical work that the calf and foot muscles need to actively output during propulsion, with part of the propulsive energy instead provided by the elastic return of the shoe plate. Research generally shows that carbon-plate running shoes with appropriate stiffness can lower oxygen uptake demand at the same pace, thereby improving running economy.

Stiffness Is Not Always Better: The Personalized Optimal Range

The relationship between bending stiffness and running economy is not linearly increasing. Excessive stiffness restricts the natural range of motion of the MTP joint, which instead increases the compensatory effort required from the calf and plantar muscles to stabilize the foot, offsetting part of the energy-return benefits. Multiple studies indicate that the optimal stiffness range is related to individual body weight, foot strike pattern (forefoot/midfoot/rearfoot), and pace—there is no single universal optimal value.

Comparison of Different Stiffness Ranges and Suitable Populations (Illustrative)

Core Research Conclusions and Practical Recommendations

• Gradual Adaptation Period: When transitioning from regular running shoes to carbon-plate shoes, a 2–4 week gradual adaptation period is recommended to allow the calf and plantar muscles to progressively adapt to the new mechanical pattern, avoiding discomfort related to the Achilles tendon or metatarsals
• Pace-Specific Selection: The energy-return benefits of carbon-plate shoes are more pronounced at faster paces (e.g., race pace); at slower training paces, the benefits are relatively limited. Whether to wear them can be decided based on training objectives
• Last and Foot Shape Matching: The carbon plate structure restricts the natural flex of the sole. If the shoe last does not match the individual’s foot shape, discomfort may be amplified or the risk of compensatory injury may increase. It is recommended to test-run before deciding
• Integration with Training Plans: The benefits of carbon-plate shoes should be viewed as an auxiliary tool within training and race strategies, rather than a replacement for foundational running technique training and strength training

Common Research Q&A (FAQ)

Q: Are carbon-plate running shoes suitable for beginners?

A: Beginners are still in the process of building their running technique and ankle strength. Wearing high-stiffness carbon-plate shoes too early may increase compensatory load. It is recommended to first establish foundational running capacity before evaluating when to introduce them.

Q: Are carbon-plate running shoes always faster than regular running shoes?

A: For most runners with a certain training foundation, carbon-plate shoes with appropriate stiffness do have the potential to improve running economy, but the actual benefit varies from person to person and is highly correlated with pace and running form. Wearing them does not guarantee being faster.

References and Academic Citations

1. Journal of Biomechanics — Research on carbon fiber plate bending stiffness and metatarsophalangeal joint mechanics.
2. Sports Medicine — Literature on running economy and personalized fitting of carbon-plate running shoes.

Related Reading

• Research Review: Biomechanical Analysis of the Effects of Carbon-Plate Running Shoe Bending Stiffness on Running Economy (RE): A Quantitative Biomechanics Experiment Report (No. 571)
• Research Review: Biomechanical Analysis of the Effects of Carbon-Plate Running Shoe Bending Stiffness on Running Economy (RE): A Quantitative Biomechanics Experiment Report (No. 1282)
• Research Review: Biomechanical Analysis of the Effects of Carbon-Plate Running Shoe Bending Stiffness on Running Economy (RE): A Quantitative Biomechanics Experiment Report (No. 1360)
• Research Review: Biomechanical Analysis of the Effects of Carbon-Plate Running Shoe Bending Stiffness on Running Economy (RE): A Quantitative Biomechanics Experiment Report (No. 913)