人在航空、航天和潜水等特殊环境中有可能吸入较高浓度CO_2,因此研究高浓度CO_2对人体影响是一项重要课題。但在文献资料中吸入CO_2条件下进行体力负荷的报导极少。有的资料指出,吸入气CO_2浓度≤3～4％可完成轻度体力负荷,5％时轻度负荷受限,但未列出实验依据。有的实验结果表明,人体吸入4％CO_22小时可耐受轻度体力负荷,但未进行更高浓度的实验。有的实验负荷强度过大,对CO_2应急允 People in the aerospace, aerospace and diving and other special environment may inhale higher concentrations of CO_2, so the study of high concentrations of CO_2 affect the human body is an important issue. However, there is very little report on the physical load under the condition of CO2 inhalation in the literature. Some sources pointed out that the suction gas CO 2 concentration ≤ 3 ~ 4% to complete a slight physical load, 5% light load is limited, but did not list the experimental basis. Some experimental results show that the body inhaled 4% CO_22 hours to tolerate mild physical stress, but did not carry out higher concentrations of experiments. Some experimental load intensity is too large, the emergency permit CO_2