lnfluence of the road and vehicle factors on the driver's organism. Paper presented at the third international meeting "Road Traffic Technique", Venezia, June 3-6, 1969.

Relative few inquiries have been carried out on the study of the physiological effect of the actual work of driving. Therefore experiments are carried out on six professional vehicle-testers, in order to establish the amount of energy expenditure, involved in driving three types of vehicles: i.e. utility, economic and medium on routes in: city centres, motorway at 60 km. 95 km. p/h., per hour, uphill and downhill roads with many curves. All the roads were open to traffic.Energy expenditure was calculated from 02 consumption determined by free circuit technique, and was found to be equivalent to energy expenditure for light work.