Background: Open water swimming has had an increasing number of competitions and participants worldwide. However, only a few studies have focused on the behavioral analysis,
particularly those based on real distance and environment (sea) situations. This study aims to investigate the characteristics of performance and temporal organization of the stroke of open water
swimmers. More specifically, to find out which resources open water athletes can draw on to achieve their goal of swimming their way through a sea race as fast as possible.
Methods:The sample consisted of 23 athletes, with a mean age of 26.4 (± 3.2) years. Their task was to swim a 1.5-kilometer open water circuit. A GPS (Garmin Fenix 3) was used to
collect performance-related variables. Images describing the temporal organization of the stroke were captured at three different time-points: beginning (B) -20-40 meters, middle (M) - 800-820 meters
and end (E) -1450-1470 meters of the course. Dependent variables related to performance (time, speed, total distance completed, as well as the stroke rates in each of the three time-points in the
course); variant aspects of swimming strokes (total time of cycle, total time of strokes, recovery [out of water] and pull-trhough [in the water] phases) and non-variant aspects of the swimming stroke
(relative timing of recovery and pull-through phases and its variability) were considered. Repeated measures analysis of variance was used to compare the three time-points of the race (B, M and E) for
all variables. Pearson correlation was used to assess the magnitude of the relationship between performance variables, while Student's t test for paired samples was used to compare the possible
differences between the right and left arms at each time-point at α≤0,05.
Results:As for performance, the results indicated that swimmers made use of stroke rate (Sr) for the three different time-points, which were higher during B compared to M and E, and
during M, lower than B and E; these changes were followed by adjustments in the variant aspects such as the total time of cycle, stroke and recovery and pull-through phases. In addition, at the three
time-points of collection swimmers had a temporal symmetry between the strokes of both arms, even though differences were observed between the phases of the stroke when arms were compared against each
other. Regarding the non-variant aspects, a change in pattern was detected between B towards M and E of the race, while at M and E time-points athletes used the same temporal structure. Regarding the
variability between variant and non-variant aspects for strokes and stroke phases, there was a decrease in magnitude through the race course. The left arm showed greater variability at the three
time-points compared to the right arm.
Conclusions:Therefore, in view of the results, it can be concluded that the resources used by skilled swimmers when swimming in a unstable environment, real conditions of distance and
environment (sea) comprise change in performance (Sf) associated with adjustments to variant aspects and of non-variant aspects of the stroke, simultaneously, depending on the moment of the race.