Does Running Speed affect the Performance Improvements Experienced by Elite Distance Runners Wearing Advanced Footwear Technology Spikes?

Elite distance runners have exhibited race time improvements since the 2020 introduction of advanced footwear technology (AFT) for track and field, also known as "super" spikes. The observed performance improvements may be due to changes in midsole compliance, which could affect leg stiffness while wearing AFT spikes. Since increased leg stiffness has been associated with running speeds greater than 6 m/s, race time improvements for elite distance runners wearing AFT spikes may be reduced at faster running speeds. To investigate the relationship between use of AFT spikes, running speed, and race performance, we conducted a statistical analysis of the race times from the top 100 male and female elite runners for 800-m to 10,000-m events from 2001 to 2023. We calculated race performance improvement (RPI) as the percentage difference between the pre-AFT spike (2001 to 2019) regression equation predicted average race times from the top 100 athletes and actual average race times from the top 100 athletes for 2021, 2022, and 2023. Overall, RPI after the introduction of AFT spikes was 0.89 ± 0.58% (range: 0.22 to 2.03%; p < 0.001) or roughly 1.2 seconds faster per kilometer than predicted by the regression equations. Additionally, average running speed is faster as race distance decreases and we found that RPI was negatively associated with running speed from 10,000-m to 800-m (p < 0.001). Although overall race performances have improved since the introduction of AFT spikes, the use of AFT spikes may disproportionately improve race performance based on running speed.