Identifying physiological determinants of 800 m running performance using post-exercise blood lactate kinetics

Purpose The aims of the present study were to investigate blood lactate kinetics following high intensity exercise and identify the physiological determinants of 800 m running performance. Methods Fourteen competitive 800 m runners performed two running tests. First, participants performed a multistage graded exercise test to determine physiological indicators related to endurance performance. Second, participants performed four to six 30-s high intensity running bouts to determine post-exercise blood lactate kinetics. Using a biexponential time function, lactate exchange ability ( γ 1 ), lactate removal ability ( γ 2 ), and the quantity of lactate accumulated (QLaA) were calculated from individual blood lactate recovery data. Results 800 m running performance was significantly correlated with peak oxygen consumption (r = −0.794), γ 1 and γ 2 at 800 m race pace (r = −0.604 and −0.845, respectively), and QLaA at maximal running speed (r = −0.657). V̇ V ˙ O 2peak and γ 2 at 800 m race pace explained 83% of the variance in 800 m running performance. Conclusion Our results indicate that (1) a high capacity to exchange and remove lactate, (2) a high capacity for short-term lactate accumulation and, (3) peak oxygen consumption, are critical elements of 800 m running performance. Accordingly, while lactate has primarily been utilized as a performance indicator for long-distance running, post-exercise lactate kinetics may also prove valuable as a performance determinant in middle-distance running.