Method for diagnosis and control of aerobic training in rats based on lactate threshold

We propose a protocol for determination of lactate threshold (LT) and test the validity of one aerobic training based on LT in rats. In group 1, V-LTi (velocity at LT before training) was determined in all rats (n=10), each rat training at its own V-LTi and in group II, animals (n=7) ran at 15 in min(-1), the mean V-LTi of group I. The training consisted of daily runs at V-LTi for 50 min, 5 days/week, for 4 weeks. In group 1, this program increased V-LT (V-LTi 14.90 +/- 1.49 in min(-1) and V-LTf, after training, 22.60 +/- 1.17 in min(-1)) and the velocity at exhaustion (19.50 +/- 1.63 in min(-1) and 27.60 +/- 1.17 in min(-1)). [Lactate] at LT (2.62 +/- 0.43 mmol L-1 versus 2.11 +/- 0.15 mmol L-1) and relative values of LT (76 +/- 3% versus 82 +/- 2%) stayed unaltered. In group II the V-LTf was 20 +/- 1.8 m (.) mim(-1), the [lactate] at the LT, 2.02 +/- 0.17 mmol (.) L-1; the exhaustion speed, 23.57 +/- 2.11 m (.) mim(-1) and relative value of LT, 82.71 +/- 2.29%. There were no significant differences in these parameters between groups I and II. Thus, this protocol based on LT is effective and the mean V-LT determined in a small number of healthy untrained rats can be used for aerobic training in a larger group of healthy animals of same gender and age. (c) 2005 Elsevier Inc. All rights reserved.