Author(s): GÁMEZ-PAYÁ, J., ITURRIAGA-RAMIREZ, T., FERNANDEZ-ELIAS, V.E., Institution: UNIVERSIDAD EUROPEA DE VALENCIA, Country: SPAIN, Abstract-ID: 1648

INTRODUCTION:
Advance footwear technology (AFT), particularly carbon fiber plates (CBP), has been linked to improvements in running economy and performance of athletes. Increased longitudinal bending stiffness and enhanced energy return are proposed mechanisms. However, most studies have assessed AFT as a single technological system, limiting understanding of the independent effects of plate. This study aims to compare the physiological response between a carbon-plated shoe (AFT) and a high-quality running conventional shoe without CBP (CONV).
METHODS:
Repeated measures crossover design was employed. Runners completed two experimental trials under identical laboratory conditions wearing either AFT or CONV, in randomized order. Participants performed a standardized incremental treadmill protocol to assess submaximal physiological response. Oxygen consumption (VO₂) was continuously measured using a metabolic cart, while capillary blood lactate (LA) was obtained at predefined exercise intensities and post-exercise. Participants were classified as Responders or Non-responders based on individual physiological changes between footwear conditions. Statistical analyses included repeated-measures ANOVA with footwear and functional group as factors.
RESULTS:
Regarding LA, levels were significantly higher with CONV (M = 5.12, SE = 0.343) compared to AFT (M = 4.19, SE = 0.227; p < .001). A significant interaction between functional group and footwear was observed; post hoc analysis revealed that Responders exhibited higher LA concentrations with CONV (M = 6.12, SE = 0.528) than with AFT (M = 4.77, SE = 0.349; p < .001), whereas no significant differences were found for non-responders (p > .05). Furthermore, Responders using CONV showed significantly higher LA levels compared to Non-responders (M = 4.11, SE = 0.438; p = .024). In terms of oxygen consumption, while no main effect was observed for footwear type (p > .05), a significant interaction was detected. Responders demonstrated higher VO₂ with CONV (M = 44.1, SE = 0.878) compared to AFT (M = 42.5, SE = 1.025; p = .009); conversely, non-responders showed higher VO₂ with AFT (M = 46.2, SE = 0.810) than with CONV (M = 44.9, SE = 0.694; p = .014).
CONCLUSION:
Contrary to literature, aggregate results showed no significant VO₂ differences between shoe conditions. However, lower lactate levels with AFT suggest metabolic benefits not captured by global oxygen uptake. Crucially, the data reveals high heterogeneity; AFT benefits are not universal but dependent on the runner’s functional profile. While 'Responders' gain metabolic advantages, 'Non-responders' experience increased oxygen cost, indicating AFT can hinder performance in some athletes. In conclusion, AFT efficacy is individual-specific. Adoption should be personalized through functional assessments to ensure metabolic gains and avoid performance decrements.