VALIDITY OF RESPIRATORY EXCHANGE RATIO AS A SECONDARY CONFIRMATION MARKER OF VO2max IN TRAINED RUNNERS

Authors

LR Bowling
EM Scudamore
SN Knight
V Pribyslavska
MJ Carder
HS Waldman
EK O'Neal

Abstract

Lynnsey R. Bowling¹, Eric M. Scudamore², Savanna N. Knight¹, Veronika Pribyslavska², Mac J. Carder², Hunter S. Waldman¹, & Eric K. O’Neal¹

¹University of North Alabama, Florence, Alabama; ²Arkansas State University, Jonesboro, Arkansas

PURPOSE: This study quantified the characteristics of and examined the validity of peak respiratory exchange ratio (RER_peak) during the last two minutes of a graded exercise test (GXT) in a sample of highly trained runners with consideration for sex and sampling interval (SI) duration. METHODS: NCAA Division I male (n = 16) and female (n = 14) cross-country runners completed a GXT running protocol that started at a velocity 2.4 km/h less than each runner’s estimated 5-km pace. Velocity increased by 0.8 km/h every two minutes until volitional exhaustion occurred. Grade was maintained at 1%. Averaged, breath-by-breath data for RER was analyzed in SI of 15, 30, and 60-s. RMANOVA was utilized to determine if RER_peak differed among SI. Independent t tests were used to compare RER_peak between sexes at each SI. Manual counts were used to determine the number of RER_peak that reached the popular 1.10 criterion marker. RESULTS: Data are presented as mean ± SEM. Cumulative RER_peak values differed (p < 0.05) among all SI (15-s 1.081 ± 0.007; 30-s 1.073 ± 0.007; 60-s 1.065 ± 0.007). RER_peak 60-s was lower than 15-s within male and female sub-cohorts (p < 0.05). There were no differences between sexes for any SI. Despite higher RER_peak with shorter SI, no SI produced a majority of runners reaching the popular criterion 1.10 value (15-s 36.7%; 30-s 33.3%; 60-s 30.0%). CONCLUSION: RER_peak was not differentiated by sex, and while statistically significant, SI selection exhibited only marginal practical differences in RER_peak. Highly trained runners familiar with severe, exhaustive running experiences were overwhelmingly unable to achieve one of the most highly utilized secondary confirmation criterion in VO_2max testing challenging the validity of this classic secondary criterion marker.

Recommended Citation

Bowling, LR; Scudamore, EM; Knight, SN; Pribyslavska, V; Carder, MJ; Waldman, HS; and O'Neal, EK (2024) "VALIDITY OF RESPIRATORY EXCHANGE RATIO AS A SECONDARY CONFIRMATION MARKER OF VO2max IN TRAINED RUNNERS," International Journal of Exercise Science: Conference Proceedings: Vol. 11: Iss. 11, Article 75.
Available at: https://digitalcommons.wku.edu/ijesab/vol11/iss11/75