Decline in the running performances of lower-ranking participants in popular road races.

Numerous studies have reported a decline in cardiorespiratory fitness (CRF) over recent decades. This study investigates whether long-term trends in running performance reflect this broader reduction in aerobic capacity. By analyzing race results across performance percentiles (90th, 50th, and 10th), the research explores how changes in endurance capacity may differ across competitive levels. Using data from the major road race Tely 10, spanning 1995 to 2020, this study examines temporal changes in running speed and estimates predicted VO₂ max as an indicator of CRF. The analysis provides valuable correlational evidence that endurance performance patterns correspond with well-documented reductions in aerobic fitness over time. The data for this study was collected through web scraping, utilizing publicly accessible information from the Tely 10 race. This method allowed for the extraction of relevant performance data over time, enabling an analysis of trends in running performance in relation to the decline in cardiorespiratory fitness (CRF). The statistical analysis using ANOVA and post-hoc Tukey's test reveals a significant decline in VO₂ max values among lower-ranking participants over the years. The data shows notable decreases in performance for these participants, indicating a broader trend of cardiorespiratory decline within the general population, which negatively impacts their running performance over time. The one-way ANOVA for both the 10th percentile and Trained runners revealed a decline in performance across decade groups. The analysis showed a high R² value of .862, suggesting a CRF decline over time.