EN
The aim of this study was to compare the effects of types of training: interval versus endurance on heart rates (HR) and the levels of chosen blood parameters in 28 Standard bred trotters, 2-3-years-old, trained for racing. The horses were divided into groups according to type of work. Three jugular venous blood samples were taken from each horse: at rest, just after the end of the training session and after 30 min rest. Hemoglobin (Hb) and lactic acid (LA) blood concentrations were determined as well as the plasma levels of glucose (Glc), glycerol, uric acid (UA), total plasma proteins and the activity of lactate dehydrogenase (LDH). Speed and HR during the training sessions were recorded by Polar speed and heart-rate telemeters. The interval training induced the increase in blood LA and Hb levels and plasma UA concentration directly proportional to the speed of trotting. A significant rise in the plasma level of glycerol determined immediately after exercise and 30 min later were observed during the intensity interval training session. These changes correlated positively with blood LA level and plasma Glc and correlated negatively with total plasma proteins concentration. The determination of plasma glycerol after exercise in trotters can be a good biochemical marker for assessing the process of interval training.