Relationships between kinematics and undulatory underwater swimming performance

Abstract

Undulatory underwater swimming (UUS) is one of the major skills contributing to performance in competitive swimming. UUS has two phases- the upbeat is performed by hip extension and knee flexion, and the downbeat is the converse action. The purpose of this study was to determine which kinematic variables of the upbeat and downbeat are associated with prone UUS performance in an elite sample. Ten elite participants were filmed performing three prone 20 m UUS trials. Seven landmarks were manually digitised to calculate eighteen kinematic variables, plus the performance variable- horizontal centre of mass velocity (V). Mean V was significantly correlated with body wave velocity (upbeat r = 0.81, downbeat r = 0.72), vertical toe velocity (upbeat r = 0.71, downbeat r = 0.86), phase duration (upbeat r = -0.79), peak hip angular velocity (upbeat r = 0.73) and mean knee angular velocity (upbeat r = -0.63), all significant at P < 0.05. A multiple stepwise regression model explained 78% of variance in mean V. Peak toe velocity explained 72% of the variance, and mean body wave velocity explained an additional 6%. Elite swimmers should strive for a high peak toe velocity and a fast caudal transfer of momentum to optimise underwater undulatory swimming performance.

Gender effect on underwater undulatory swimming technique of young competitive swimmers

“…They claim that its value largely determines underwater swimming velocity. It is known that the ability to obtain high vertical velocity of the toes is the basis for effective movement using the underwater undulatory swimming technique [4], [10]. In this study, the values of the product de-fined in this way were: 1.05 (girls) and 1.15 (boys).…”

“…It cannot be ruled out that lower A ROM values in the boys' group were associated with an increase in extensional movement in hip joints. This possibility was suggested, among others, by Higgs et al [10]. Unfortunately, this issue was not the purpose of research.…”

“…This is due to the fact that swimmers move this way after the start and after every turn in almost all races. The exception is the breaststroke, for which the underwater phase is limited by swimming regulations [10].…”

“…Typically, the distinction of such division was vertical displacement of the toes [9]. In this way, the upward and downward movements were distinguished, while describing both phases using kinematic variables [4], [9], [10]. On this basis, the similarities and differences of the collected spatial-temporal indicators were assessed.…”

“…In light of this, the course of the underwater undulatory swimming carried out by humans and some water mammals was also compared [25]. In the course of these studies, it was found that achieving high swimming velocity with the use of underwater undulatory swimming is possible, among others, due to the increase in the vertical velocity of the toes (increase in the frequency of movements while maintaining their appropriate breadth), large plantar and small knee joint flexion as well as maintaining proper spatial-temporal relationships between individual segments [7], [10], [22]. Also important was the observation that the values of kinematic variables describing the upward and downward movements were definitely similar to each other [4], [9].…”