Predictability of blood lactate concentration after exercise in horses working at speeds that were guided by results of an exercise stress test. Part 2: Relation between heart rate during exercise and blood lactate concentration after exercise

Pferdeheilkunde 17Genauigkeit der Steuerung der Laktatkonzentration im Blut von Pferden nach Belastungen After exercise at v 4 for 5, 15 and 25 minutes they were 163 beats/min, 166 beats/min and 164 beats/min respectively.The heart rate during exercise of the same duration was always higher after exercise at v 4 than at v 2.5 (p < 0.01 to p < 0.001).The effect of exercise duration on heart rate during exercise was very small.Between and within horses there were large variations of the heart rate during exercise.The blood lactate concentration after exercise and the heart rate during exercise related in three out of six exercise types only.The relations were not very close and in one case it was positive and in the other two negative.Thus it does not make sense to guide exercise intensity by a defined heart rate during exercise if it is aimed to condition a specific energetic pathway.To evaluate the predictability of heart rate during exercise the difference was calculated between the measured and the expected values HR 2.5 or HR 4 .The median of the difference between measured and expected heart rate during exercise was for exercise at v 2.5 for 5, 15 and 25 minutes +1 beat/min, -2 beat/min und -2 beat/min respectively, for exercise at v 4 for 5, 15 and 25 minutes it was -7 beats/min, -2 beats/ min und -3 beats/min respectively.Despite the large day by day and interindividual variations of the heart rate during exercise guidance of exercise intensity by means of heart rate derived from exercise tests may be reasonable.However, studies to demonstrate whether this approach is effective and better than other methods await to be done.