To elucidate further the special nature of anaerobic threshold in children, 11 boys, mean age 12.1 years (range 11.4-12.5 years), were investigated during treadmill running. Oxygen uptake, including maximal oxygen uptake (VO2max), ventilation and the "ventilatory anaerobic threshold" were determined during incremental exercise, with determination of maximal blood lactate following exercise. Within 2 weeks following this test four runs of 16-min duration were performed at a constant speed, starting with a speed corresponding to about 75% of VO2max and increasing it during the next run by 0.5 or 1.0 km.h-1 according to the blood lactate concentrations in the previous run, in order to determine maximal steady-state blood lactate concentration. Blood lactate was determined at the end of every 4-min period. "Anaerobic threshold" was calculated from the increase in concentration of blood lactate obtained at the end of the runs at constant speed. The mean maximal steady-state blood lactate concentration was 5.0 mmol.l-1 corresponding to 88% of the aerobic power, whereas the mean value of the conventional "anaerobic threshold" was only 2.6 mmol.l-1, which corresponded to 78% of the VO2max. The correlations between the parameters of "anaerobic threshold", "ventilatory anaerobic threshold" and maximal steady-state blood lactate were only poor. Our results demonstrated that, in the children tested, the point at which a steeper increase in lactate concentrations during progressive work occurred did not correspond to the true anaerobic threshold, i.e. the exercise intensity above which a continuous increase in lactate concentration occurs at a constant exercise intensity.
To evaluate whether anaerobic threshold criteria evaluated in adults are pertinent to children, ten boys with a mean age of 11.2 years were investigated during treadmill running. Maximal running velocity was determined at stepwise increasing load, with determination of blood lactate following exercise. On the following days four runs each lasting 16 min were performed at a constant speed starting with a speed corresponding to about 70% of the maximal speed and increasing it during the next run in order to determine maximal steady state levels of blood lactate. Blood lactate was measured at the end of every 4 min period. From this date the anaerobic threshold was calculated. The correlation between anaerobic threshold values and maximal steady state levels of blood lactate was poor, however, a steady state of blood lactate was present at 4.6 mmol/l, whereas the mean anaerobic threshold value was determined at 2.6 mmol/l. In view of our results, the anaerobic threshold during increasing work does not correspond to the true anaerobic threshold, which can be assumed to occur at much higher lactate values. The meaning of the term anaerobic threshold is therefore to be questioned.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with đź’™ for researchers
Part of the Research Solutions Family.