Relationships of anaerobic threshold and onset of blood lactate accumulation with endurance performance

Summary

This study was undertaken to compare the contribution of both the anaerobic threshold (AT) and onset of blood lactate accumulation (OBLA) with endurance performance in eleven non-endurance trained active male adults. AT determination was based upon both blood lactate and gas exchange criteria, while OBLA was determined as the point corresponding to a blood lactate concentration of 4 mmol·l⁻¹. A dependent t-test revealed significantly higher values for OBLA related variables as compared with corresponding AT related variables, thereby validating the comparison of these two categories of variables in relation to endurance performance. Approximately 67, 60, 37, and 50% of the variance in endurance performance were accounted for by $\dot V$O₂ (ml · kg⁻¹ · min⁻) AT-WR, OBLS-$\dot V$O₂ (ml · kg⁻¹ · min⁻), and OBLA-WR, respectively. When AT-HR (X₂) was added to the $\dot V$O₂ (X₁) as another predictor, the contribution of these variables to endurance performance increased appreciably to 84%. The resultant multiple regression equation was Y=−4.564 X₁+2.68 IX₂+90.6 (SEE=9.9 s). Consequently, it is suggested that variables related to an abrupt increase in blood lactate, together with several gas exchange responses, could explain endurance performance in a shorter distance to a greater extent than variables related to a rigid threshold of 4 mmol·l⁻¹.