Relationship Between Heart Rate Regulation Types and Specific Work Capacity in Sprint Swimmers

This article examines the relationship between heart rate regulation types and specific work capacity in sprint swimmers. The purpose of the article is to identify the characteristics of the dynamics of specific work capacity in sprint swimmers with different heart rate regulation types 6 and 24 hours after a training session. Research results: Overall, among swimmers with a normotonic type of heart rate regulation, changes in the studied indicator ranged from −0.11 to +0.43. The largest increase was observed after the 75-meter exercise (+0.43), while the smallest change in absolute value was observed after the 4×50-meter exercise (−0.11). All p-values reported were greater than 0.05. This suggests the absence of statistically significant differences based on the presented results, but does not prove the complete absence of physiological changes or the equivalence of indicators at the two time points. Conclusions. In a study of 64 swimmers aged 18–22 who specialized in freestyle sprint distances, the dynamics of specific work capacity were analyzed 6 and 24 hours after a training session, depending on the type of heart rate regulation. After 6 hours, the highest pooled mean of the four test indicators was observed in the group with a normotonic regulation type (99.74%), and the lowest was observed in the group with a markedly vagotonic type (98.70%). In the groups with the sympathicotonic and moderately vagotonic types, the corresponding values were 98.88% and 99.53%. After 24 hours, the highest overall mean was recorded in the group with a moderately vagotonic type of regulation (100.03%); the value in the group with a normotonic type was close to this (99.98%). In the group with the sympathicotonic type, the indicator was 99.39%, and in the group with the markedly vagotonic type, it was 98.98%. Between the 6th and 24th hours, the generalized indicators increased in all groups. The largest descriptive increase was observed in the groups with sympathicotonic and moderately vagotonic types of regulation—approximately 0.51 percentage points. This characterizes the dynamics of the mean values but does not prove the statistical significance of the changes.