A new approach for the determination of anaerobic threshold: methodological survey on the modified Dmax method

Abstract

Siahkouhian M, Azizan S, Roohi BN. A new approach for the determination of anaerobic threshold: methodological survey on the modified D max method. J. Hum. Sport Exerc. Vol. 7, No. 2, pp. 599-607, 2012. A wide variety of diagnostic techniques can be found in the literature for anaerobic threshold (AT) assessment. The aim of this study was to investigate if the heart rate (HR) at the modified D max method (Mod-D max ) using parallel straight line slope (PSLS) mathematical model and the Narita target heart rate equation was comparable with the HR measured at the AT by the continuous respiratory gas measurements in healthy young girls. Eight (age 19.29±1.70 years) healthy young girls performed an exhaustive treadmill exercise test for determination of the HR at Mod-D max using PSLS model and Narita equation. The AT of the participants was also calculated by the continuous respiratory gas measurements according to the Craig method. There was no significant difference between the HR determined at the Mod-D max method and the HR measured at the AT by the continuous respiratory gas measurements (167±9.22 vs. 165.25±6.32 b/min). Bland and Altman plots revealed a good agreement between the determined HR at Mod-D max and values of the HR measured at the AT by the continuous respiratory gas measurements (95% CI =−20 to+22.8 b/min). According to the results, the Mod-D max using PSLS model and the Narita equation during the exhaustive treadmill exercise test is an accurate and reliable noninvasive alternative to the cumbersome, expensive, and time-consuming invasive methods. Therefore, the Mod-D max method can be used for the determination of AT in healthy young girls.

Profiling the Aerobic Window of Horses in Response to Training by Means of a Modified Lactate Minimum Speed Test: Flatten the Curve

“…The inflexion point at which the distance between the line and the lactate regression curve is maximal is annotated as the D max value, and represents the threshold point at which a steady-state is reached between lactate production and elimination ( Zhou and Weston, 1997 ). Human studies report that the D max approach is suitable to define the individual lactate threshold to exercise and provides a good estimation of the MLSS ( Zhou and Weston, 1997 ; Siahkouhian et al, 2012 ; Zwingmann et al, 2019 ). In contrast, a study of Janeba et al (2010) , concluded that the D max approach is not a valid method because of the high dependence on the lowest and highest workload data points of the lactate curve ( Janeba et al, 2010 ).…”

“…In contrast, a study of Janeba et al (2010) , concluded that the D max approach is not a valid method because of the high dependence on the lowest and highest workload data points of the lactate curve ( Janeba et al, 2010 ). Therefore, the Modified D max has been developed, though controversies regarding its ability or inability to estimate the MLSS remains ( Janeba et al, 2010 ; Siahkouhian et al, 2012 ; Płoszczyca et al, 2020 ).…”