The detected concentrations of the changes in endtidal expired air hydrocarbons, alcohols, lower fatty acids and acetone show that the contents remain in as follows : carbon dioxide, 2.9 〜 7.0% ; methane, 1.0 〜 12.6 ppm ; n-hexane, 0.0028 〜 0.085 ; methanol, 0.036 〜 0.229 ; ac-etaldehyde, 0.023 〜 1.20 ; ethanol, 0.0068 〜 3.78 ; acetone, 0.021 〜 0.99 acetic acid, 0.024 〜 0.049 ; propionic acid, 0.0014 〜 0.020 ; iso-butyric acid, 0.00010 〜 0.00042 ; n-butyric acid, 0.00022 〜 0.0044 ; iso-valeric acid, less than 0.00010 〜 0.00068 ; n-valeric acid, less than 0.00010 〜 0.00098 (in ppm), respectively.
　The relationship between carbon dioxide and methane, and alcoh-ols, lower fatty acids and acetone in end tidal expired air of volunteer normal students in preloading was reasonable finely.
　However, metabolic pathway of alcohols, aldehydes and lower fatty acids of a male in many physical exercise training was not clear.

DESCENTE SPORTS SCIENCE Vol.14/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE