ANAEROBIC THRESHOLD IN RATS

1. The aim of this study was to find out whether the anaerobic thresho ld (AT) can be estimated in rats running at increasing speed and if so what is the reproducibility of the measurements. 2. Lactate (LA) conc entrations in blood taken from 11 rats were determined during a discon tinued, multistage treadmill exercise test repeated four times in each animal. 3. It was found that blood LA changes vs speed have an expone ntial pattern with a distinct, rapid rise at the speed above 25 m/min which corresponds to blood LA of approx. 4 mmol/l. 4. The variation co efficient of the speed at which AT occurred in individual animals rang ed between 10 and 20%. 5. These results offer a potential application of AT determination in the animal studies concerning mechanisms contro lling exercise metabolism.