| （School of Physical Education，South China Normal University，Guangzhou 510006，China） Abstract: By measuring the changes of such indexes as gas metabolism and blood lactic acid of 10 students major-ing in physical education during load gradually increased exercising in normal and simulated 1,000m and 1,500m hypoxic environments, the authors observed the effects of hypoxia on the body’s lactic acid threshold and ventila-tion threshold, and revealed the following findings: 1) in the three environments, the ventilation thresholds are (720.0±71.8) s, (631.1±60.1) s and (616.0±40) s respectively; the lactic acid threshold times are (826.67±72.11) s, (816.00±94.66) s and (744.00±94.66) s; 2) with the decrease of partial oxygen pressure, the ventilation threshold appeared earlier than the lactic acid threshold, and the absolute value of such indexes as ventilation threshold and lactic acid threshold decreased, but their percentage changed little; 3) in a normal environment, the coefficient of correlation between lactic acid threshold and ventilation threshold r>0.65(P<0.05), but in simulated 1,000m and 1,500m hypoxic environments, r<0.60(P>0.05). Conclusions: 1) such indexes as ventilation threshold and lactic acid threshold as well as their percentage can be used to measure or evaluate sports training effects and to guide sports training; 2) for training in a place at a higher altitude, the exercise intensity should be appropriately adjusted, so that the athletes can adapt to the change of environment.
Key words: sports physiology；hypoxia；gas metabolism；ventilation threshold；lactic acid threshold |
