Abstract

Exercise with stepwise increasing work loads until exhaustion leads to a curvilinear increase of lactate in blood and typical lactate kinetics in the post-exercise period. Lactate kinetics in blood during exercise and recovery results from diffusion along gradients between muscle and blood and simul- taneous elimination. Therefore, a general diffusion-elimination model is presented from which maximal rate of elimination, individual anaerobic threshold (IAT), gradient between muscle and blood, muscle volume working above the IAT, individual membrane constant, wantity of lactate accounting forlactate gradient, and whole body lactate can be obtained. For demonstration purposes, this model was applied to a highly trained athlete. In this example,all constants and variables mentioned above as well as an equation reflecting individual lactate kinetics were calculated. Furthermore, the IAT was determined in 61 athletes participating in different events. In general, it can be demonstrated that with increasing aerobic capacity the lactate concen- tration at the IAT decreases. The lactate concentration at the IAT varies interindividually within broad limits, thus emphasizing the need for indivi- dual assessment. Verf.-Referat