VO2 AND RER AT 90% OF 8-KM RACE PACE MOST ACCURATELY REPRESENTS RUNNING ECONOMY

Authors

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

Abstract

Trace A. Dominy¹, Savanna N. Knight¹, Lynnsey R. Bowling¹, Mac J Carder², Eric M. Scudamore², Veronika Pribyslayska²,Hunter S. Waldman¹, & Eric K. O’Neal¹

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

Oxygen consumption (VO₂) and respiratory exchange ratio (RER) are two metabolic components that are often assessed in running economy (RE) studies. However, for runners competing in shorter long-distance running events, such as collegiate cross-country runners, the slower paces often assessed may not be strongly related to competition velocity metabolic values. PURPOSE: To determine which percentage of VO₂ and RER at sub-maximal race pace most strongly correlated with actual race pace velocity. METHODS: Sixteen NCAA Division I, male distance runners performed their habitual warm-up before completing four, 5-minute RE bouts at 70, 80, 90, and 100% of personal best 8-km respective race paces from their previous season in a counter-balanced order with 5 min of passive recovery between bouts. VO₂ and RER were collected and averaged in 60 s increments across the final two minutes of each RE bout. Pearson’s r correlation coefficient was conducted to determine strength of these relationships with sub-maximal and personal best race pace values. RESULTS: VO₂ r ranged from 0.84-0.88 for all submaximal paces (p < 0.05) signifying no preferable race pace to be used for assessment of VO₂. However, RER of both 70% (r = -0.21; p = 0.44) and 80% (r = -0.04; p = 0.89) of race pace intensity produced not only weak but inverse relationships with race pace RER. Only 90% of race pace produced a weak-moderate positive relationship with RER at 100% race pace (r = 0.36; p = 0.17). CONCLUSIONS: Metabolic cost is a more comprehensive indicator of RE than VO₂ alone but cannot be calculated if RER exceeds 1.00. Four runners (25%) in this study exceeded an RER of 1.00 when running at race pace. This study indicates when assessing RE for male runners that compete at shorter long-distance running events, VO₂ alone may not be a valid indicator of RE, particularly at lower velocities.

Recommended Citation

Dominy, TA; Knight, SN; Bowling, LR; Carder, MJ; Scudamore, EM; Pribyslavska, V; Waldman, HS; and O'Neal, EK (2024) "VO2 AND RER AT 90% OF 8-KM RACE PACE MOST ACCURATELY REPRESENTS RUNNING ECONOMY," International Journal of Exercise Science: Conference Proceedings: Vol. 11: Iss. 11, Article 59.
Available at: https://digitalcommons.wku.edu/ijesab/vol11/iss11/59