RT Journal Article T1 Highest oxygen consumption prediction: introducing variable theoretical proportional factors for diferent sports A1 Lorenzo Capellá, Irma A1 Ramos Álvarez, Juan José A1 Jiménez Herranz, María Elena A1 Padulo, Johnny AB Purpose The use of a fixed theoretical-proportional-factor (TPF15) is one of the indirect highest-oxygen-consumptions (HOC)assessment methods, but it may not accurately reflect the physiological differences across various sports (cycling-triathlon-running-football-multisport). The aim of this study is to evaluate the variability of TPF across different sports, proposing aseries of sport-specific new TPF values for more accurate HOC estimation.Methods A sample of 340 adults (26.01 ± 7.18 years) performed a maximal-incremental-test using sport-specific-ergometers.HOC was considered for cycling ̇ VO2peak , whereas for the other investigated sports it was considereḋVO2max . HOC wasdirectly measured using a gas-analyzer, and TPF values were calculated using heart rate (HR): the ratio of HR max /HR restmultiplied for the measured values of HOC. A one-way ANOVA was used to measure differences and Bland–Altman plotswere constructed to compare predicted and actual ̇ VO2max/̇VO2peak.Results Actual HOC was significantly greater than those predicted by the fixed TPF 15 (P < 0.001). Sport-specific newTPF values ranged from 16.55 in multisport to 20.15 in cycling, consistently exceeding the old fixed TPF 15 , and predict-ing therefore better HOC. The new TPF exhibited a closer agreement with the directly measured ̇ VO2max/̇VO2peak com-pared to the TPF 15 . Furthermore, the new TPF reduced the typical-measurement-error (14.94–17.78%) compared to TPF 15(15.63–24.13%).Conclusion This study suggests that new TPF values predict ̇ VO2max/̇VO2peak with higher accuracy compared to the traditionalmethod. The use of HR max and HR rest values allows to customize training programs for different athletes. Future researchshould focus on validating these findings across larger populations of athletes PB springer SN 1439-6319 YR 2024 FD 2024-10-08 LK https://hdl.handle.net/20.500.14352/118032 UL https://hdl.handle.net/20.500.14352/118032 LA eng NO Lorenzo-Capellá, I., Ramos-Álvarez, J.J., Jiménez-Herranz, M.E. et al.. Highest oxygen consumption prediction: introducing variable theoretical proportional factors for different sports. Eur J Appl Physiol (2024). https://doi.org/10.1007/s00421-024-05625-w DS Docta Complutense RD 10 abr 2025