The effects of footwear midsole longitudinal bending stiffness on running economy and ground contact biomechanics: A systematic review and meta‐analysis

Abstract

This study aimed to address the effects of increased longitudinal bending stiffness (LBS) on running economy (RE) and running biomechanics. A systematic search on four electronic databases (Pubmed, WOS, Medline and Scopus) was conducted on 26 May 2021. Twelve studies met the inclusion criteria and were included. Standardised mean difference with 95% confidence intervals (CI) between footwear with increased LBS vs. non-increased LBS conditions and effect sizes were calculated. To assess the potential effects of moderator variables (type and length plate, increased LBS, shoe mass and running speed) on the main outcome variable (i.e. RE), subgroup analyses were performed. Increased LBS improved RE (SMD = −0.43 [95% CI −0.58, −0.28], Z = 5.60, p < 0.001) compared to non-increased LBS. Significant increases of stride length (SMD = 0.29 [95% CI 0.10, 0.49], Z = 2.93, p = 0.003) and contact time (SMD = 0.17 [95% CI 0.03, 0.31], Z = 2.32, p = 0.02) were found when LBS was increased. RE improved to a greater degree at higher running speeds with footwear with increased LBS. RE improved 3.45% with curve plate compared to no-plate condition without improvements with flat plate shoes. When shoe mass was matched between footwear with increased LBS vs. non-increased LBS conditions, RE improved (3.15%). However, when shoe mass was not controlled (experimental condition with ∼35 grams extra), a significant small improvement was found. These RE improvements appear along with an increase of stride length and contact time. Shoe mass, type of plate (flat or curve) and running speed should be taken into consideration when designing a shoe aimed at improving long-distance running performance. KEYWORDSCarbon-fibre plate; vaporfly; energy cost of running; performance Highlights. Shoes with relatively high longitudinal bending stiffness (but not very stiff) improve running economy compared to conventional shoes. . The oxygen cost reduction was influenced by the mass of the shoe, the type of plate and the running speed. . The running economy improvements appear along with an increase of stride length and contact time.

The Impact of Grounding in Running Shoes on Indices of Performance in Elite Competitive Athletes

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Effects of footwear with different longitudinal bending stiffness on biomechanical characteristics and muscular mechanics of lower limbs in adolescent runners

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Running economy and lower extremity stiffness in endurance runners: A systematic review and meta-analysis

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