Ventilation threshold and lactate threshold of 9-12 year-old boys and girls / 体力科学

ABSTRACT

Ventilation threshold (VET), threshold of decompensated metabolic acidosis (TDMA) and lactate threshold (LT<SUB>1</SUB>, LT<SUB>2</SUB>) were investigated during incremental bicycle exercise for 20 boys (11.7±0.1 years) and 10 girls (11.2±0.2 years) .<BR>Maximum oxygen uptake (VO<SUB>2</SUB>max) was measured by treadmill running. There was significant difference between boys and girls in VO<SUB>2</SUB>max per body weight, but no signif-icant difference per LBM. Mean values of each threshold (% peak VO<SUB>2</SUB>) were as follows. VET was 53.3±2.2%, TDMA was 69.0±2.2%, LT<SUB>1</SUB>was 51.8±2.2% and LT<SUB>2</SUB>was 72.8±2.2%. These values were not higher than those of previous adult's data. There was no significant difference in lactate and ventilatory parameters between boys and girls, except LT<SUB>2</SUB>and LT<SUB>4</SUB>mM.<BR>In conclusion, it seems that no difference is seen in lactate and ventilatory responses between 9-12 year boys and girls. VET and TDMA by bicycle exercise could be estimated by ventilatory responses in prepubertal children.