Keywords
bradycardia
swimming exercises
heart
vagus
How to Cite
Abstract
The aim of the study was to determine the heart rate in 12-13-week-old rats under conditions of a 6-week dosed swimming load. In general, rat swimming is considered one of the best methods for studying cardiological parameters and the adaptive capabilities of the heart. As part of our study, we ensured 12-13-weeks-old male rats to undergo dosed swimming exercises for 4 and 6 weeks, at the end of each week we studied the electrocardiographic data of rats in order to assess the dynamics of changes in the frequency of contractions in experimental groups. The rats were divided into 3 groups: 1) a control group that did not receive any load (n=6); 2) The frst study group was subjected to a daily 30-minute swimming load for 4 weeks with a weight in the amount of 3% of the body weight of the rat (n=6) attached to the tail, 3) The second study group, which was subjected to a daily 60-minute swimming exercise for 6 weeks, the weight of the load attached to the tail amounted to 4% of the weight of the rat (n=6). Significant changes in cardiac contractility were observed only in experimental rats (30-minute exercise with a load of 3% of body weight or a 60-minute load with a load of 4% of body weight). In most rats, initial tachycardia was followed by prolonged bradycardia. The mentioned study can be considered as another step forward in the study of the pathogenetic mechanisms of pathological changes in rhythm and frequency that occur during exercise.
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