Abstract

The global of this paper is a critical evaluation of the use of mathematical models for a calculation of dynamic anaerobic energy balance. Trained road cyclists underwent a constant duration (60 sec) bicycle ergometer test, with the brake force fixed in order to achieve individually different work loads by change of the pedalling rate. From lactate measurements obtained during recovery we estimated total lactate production using a mathematical compartmental model of lactate kinetics. Via the energy equivalent of the lactate formed, lactic energy production could be calculated. Alactic energy production was determined, based on the assumption of a constant phosphocreatine concentration per unit mass of muscle, using the estimated muscle mass of the volunteer and the corresponding energy equivalent. The components of aenaerobic energy production thus estimated were put into relation to total energy expenditure, determined from directly measured pedalling rate on the ergometer, brake force and mechanical efficiency. Balancing the different components of energy release necessary to perform the 60 second ergometer test, we found that about 15 of total expenditure were supplied with anaerobic-alactic mechanisms and about 60 with anaerobic-lactic energy production. 25 of the energy requirements can be appointed to oxidative energy liberation. This fact leads to the conclusion that for the estimation of global anaerobic capacity a 60 sec ergometer test is insufficient because of overabundant duration. Verf.-Referat