Determinants of 800-m and 1500-m Running Performance Using Allometric Models

Abstract
Purpose: To identify the optimal aerobic determinants of elite, middle-distance running (MDR) performance, using proportional allometric models. Methods: Sixty-two national and international male and female 800-m and 1500-m runners undertook an incremental exercise test to volitional exhaustion. Mean submaximal running economy (ECON), speed at lactate threshold (speedLT), maximum oxygen uptake (V˙O2max), and speed associated with V˙O2max (speedV˙O2max) were paired with best performance times recorded within 30 d. The data were analyzed using a proportional power-function ANCOVA model. Results: The analysis identified significant differences in running speeds with main effects for sex and distance, with V˙O2max and ECON as the covariate predictors (P < 0.0001). The results suggest a proportional curvilinear association between running speed and the ratio (V˙O2max·ECON−0.71)0.35 explaining 95.9% of the variance in performance. The model was cross-validated with a further group of highly trained MDR, demonstrating strong agreement (95% limits, 0.05 ± 0.29 m·s−1) between predicted and actual performance speeds (R2 = 93.6%). The model indicates that for a male 1500-m runner with a V˙O2max of 3.81 L·min−1 and ECON of 15 L·km−1 to improve from 250 to 240 s, it would require a change in V˙O2max from 3.81 to 4.28 L·min−1, an increase of Δ0.47 L·min−1. However, improving by the same margin of 10 s from 225 to 215 s would require a much greater increase in V˙O2max, from 5.14 to 5.85 L·min−1 an increase of Δ0.71 L·min−1 (where ECON remains constant). Conclusion: A proportional curvilinear ratio of V˙O2max divided by ECON explains 95.9% of the variance in MDR performance.