The Relationship of Sprint Interval Training Performance and 100-m Freestyle in Adolescent Swimmers: A Complex Network Model Approach

Sprint interval training (SIT) is commonly used to improve the anaerobic capacity of swimmers, but the overall correlation between SIT and 100-m freestyle performance and the role of key parameters in the correlation have not been fully investigated. This study employs a complex network model to analyze the overall correlation between SIT and 100-m freestyle performance and its segmental kinematic parameters, and further explores the key parameters in the relationship network through network centrality indicators. Sixteen adolescent swimmers participated in the study, completing 6×50 m SIT and 100-m freestyle tests. An undirected weighted complex network model was constructed, which included kinematic, metabolic, and RPE collected from both tests. The complex network composed of multiple performance variables of SIT and 100-m freestyle reached the maximum scale, with dense connections between nodes, and some nodes exhibited a modular correlation, but to a lesser degree. The degree centrality and PageRank of the stroke length parameters of SIT and the free-swimming segment for the 100-m freestyle were higher. The closeness centrality of the stroke length of the free-swimming segment and sprint speed of the 100-m freestyle was higher. The betweenness centrality of the stroke length of the latter part of the free-swimming segment, turn, and sprint speed for 100-m freestyle was higher. The vector centrality of SIT speed and the overall speed of 100 meters, as well as the time for the first 15 meters, was higher. The complex network model can be used to evaluate the complex relationship between high-intensity training performance and multiple competitive swimming performance variables in the field of swimming. The overall correlation between SIT and 100-m freestyle is tight, with a network characteristic of partially condensed variable correlations. Stroke length and speed are the key parameters in this relationship, where stroke length is an important factor for correlation rate, and speed may potentially affect the quantity and quality of correlations. The stroke length of the latter part of the free-swimming segment, turn, and sprint speed for 100-m freestyle play an important mediating role in the correlation between SIT and 100-m freestyle performance.