VO2 AND RER AT 90% OF 5-KM RACE PACE MOST ACCURATELY REPRESENTS RUNNING ECONOMY

Authors

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

Abstract

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

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

PURPOSE: Running economy (RE) is often assessed at velocities considerably lower than actual race pace. Therefore, the purpose of this study was to examine the relationships of VO₂ and RER at submaximal intensities to 5-km race pace in NCAA Division I collegiate cross-country female runners. METHODS: Thirteen runners completed four 5-minute running economy (RE) bouts at 70, 80, 90, and 100% of their individual race pace in a single session. A difference in oxygen consumption (VO₂) of < 0.1 L/min was used to determine steady state. If steady state was not achieved in 5 minutes, the bout continued for another minute. A 5 min passive rest was included between each RE bout. Throughout each bout, VO₂ and respiratory exchange ratio (RER) were collected in 60 second intervals via indirect calorimetry (TrueOne 2400, Parvo Medics Inc., Sandy, UT). To determine correlation strength between submaximal cardiorespiratory measures and those at race pace, Pearson’s correlation coefficient was conducted. RESULTS: VO₂ at 70, 80 and 90% were all found to have strong (p < 0.01) correlations with race pace with VO₂ for 80 and 90% being the strongest (r = 0.96 and 0.95, respectively). RER did not result in a similar trend. RER at 90% was highly correlated with race pace (r = 0.81) versus the lower intensities (70% r = 0.28; 80% r = 0.45). CONCLUSIONS: Energy cost at race pace for shorter distance endurance races often cannot be calculated due to elevated RER values (> 1.00). The current data indicates RE bouts designed to match 90% of race pace velocity can produce steady state VO₂ and produce significantly stronger correlations with race pace RER.

Recommended Citation

Knight, SN; Bowling, LR; Carder, MJ; Scudamore, EM; Pribyslavska, V; Waldman, HS; and O'Neal, EK (2024) "VO2 AND RER AT 90% OF 5-KM RACE PACE MOST ACCURATELY REPRESENTS RUNNING ECONOMY," International Journal of Exercise Science: Conference Proceedings: Vol. 11: Iss. 11, Article 91.
Available at: https://digitalcommons.wku.edu/ijesab/vol11/iss11/91