ABSTRACT
<p><b>OBJECTIVE</b>To study the suitable oxygen concentration in hypoxic preconditioning.</p><p><b>METHODS</b>Short-term and long-term intermittent hypoxia modes were designed and the effects of various oxygen concentrations on body weight, blood oxygen saturation, swimming capability were analyzed.</p><p><b>RESULTS</b>The rate of body weight gain in rat model decreased gradually when exposed to hypoxia environment for long time. When the concentration of oxygen changed from 15% to 8%, accompanied with the decreasing of oxygen concentration, a platform was observed in blood oxygen saturation of rat model after hypoxic preconditioning training. Rat swimming capability improved significantly. After trained in 10% hypoxia environment, the swimming capability of kunming mice improved obviously.</p><p><b>CONCLUSION</b>Proper level of hypoxic preconditioning training could improve hypoxia tolerance and enhance the rat sport capability significantly. 15%-10% oxygen concentration range could be regarded as a helpful effective area for hypoxic preconditioning, 10% oxygen concentration might be the eligible concentration for hypoxic preconditioning training.</p>