Cardiovascular responses to laughter: A pilot project

The purpose of this study was to determine cardiovascular responses to laug hter. The CO2 rebreathing method was used to determine cardiac output and u nderstand the role of the central and peripheral components of oxygen consu mption and its relation to energy expended. Eight college-age subjects part icipated in this study. During periods of 5 minutes each, while sitting in a comfortable chair, subjects first rested, then viewed a videotape of a we ll-known comedian, then remained sitting. A repeated-measures analysis of v ariance was used to analyze the data. During laughter, there were significa nt increases in stroke volume and cardiac output and significant decreases in arteriovenous oxygen difference and total peripheral resistance. Followi ng laughter there was a significant decrease in oxygen consumption. Copyrig ht (C) 2000 by W.B. Saunders Company.