The effect of ingestion of alcohol on human respiratory exchange (oxygen consumption and R. Q.) during rest and muscular work

Summary

Comparisons are drawn of metabolism measurements made on a man under basal conditions, after ingestion of 30 and 50 cc., respectively, of absolute alcohol in a 250-cc. water solution, and after control doses of water and saccharin. With theBenedict helmet and opencircuit system observations were made with the subject at rest, during work (bicycle ergometer), and during recovery following work. Each experiment lasted 3 hours and comprised consecutive periods, usually of 15 minutes' duration. The work was performed immediately after or 1 hour after ingestion of the dose and lasted for 1 hour at the rate of 275 kg./m., 1/2 hour at 550 kg./m., 2 hours at 275 kg./m., or 2 hours at 415 kg./m. per minute.

The metabolism of alcohol, as indicated by the course of the R. Q. and the oxygen absorption, proceeded at about the same rate irrespective of whether the subject was at rest or engaged in muscular activity. This was true in all experiments save those when the subject rested for 1 hour before beginning work after alcohol ingestion. These exceptions suggest that the period of time during which work is done after alcohol ingestion may be of effect upon the rate of alcohol combustion.

The efficiency of performance of work (relation between the heat equivalent of work performed and the energy expenditure) was slightly greater in some experiments, slightly lower in others, and practically unchanged in others after alcohol ingestion.

Calculation of the increments above the pre-work base-line values in R. Q., carbon-dioxide production, and oxygen consumption in the periods of work and recovery following alcohol ingestion and calculation of the changes in catabolism of carbohydrate and fat during work and recovery lead also to the conclusion that muscular work does not increase the combustion of alcohol. Comparison of the heat production of the subject when at rest and at work and after ingestion of the control and alcohol doses gives no indication of a summation of the separate effects of alcohol ingestion and muscular work when both these factors are superimposed upon the basal metabolism.