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Detraining Effect on Sprint Swimming Performance and Load-Velocity Profile
Jesús J Ruiz-Navarro1, Óscar López-Belmonte1, Adrián Febles-Castro1
1Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain.
Purpose:
To assess the effect of 5-week training-cessation period on performance and load-velocity profile-related variables.
Methods:
Twenty-four competitive swimmers (15 male and 9 female: 19.2 [3.7] and 17.3 [2.3] y, 50-m front-crawl 550 [70], and 572 [51] World Aquatics points, respectively) performed a 50-m front-crawl all-out swim, a load-velocity profile, and a pull-up test before and after a 5-week off-season period. Kinematic variables, blood lactate concentration, and rating of perceived exertion were monitored during the load-velocity profile tests.
Results:
Performance was impaired 1.3% for males (P < .01) and 3.8% for females (P < .01). Neither anthropometric changes (males r2 = .277, females r2 = .218, P > .05) nor the physical activity performed during the off-season (males r2 = .329, females r2 = .094, P > .05) attenuated performance impairments. While males counteracted the stroke-rate decline (P < .05) by increasing stroke length (P < .05) in the majority of the race, females did not, leading to a decline in clean swimming speed (P < .05). The maximum load at zero velocity decreased (P < .05) during the load-velocity profile test. In addition, males showed an increased blood lactate concentration (P < .05), whereas females decreased the maximum velocity at zero load (P < .01) and stroke rate (P < .01). No change in the slope was observed for either sex (P > .05).
Conclusion:
Following a 5-week off-season period, sprint swimming performance declines (males 0.34 s; females 1.15 s). The load-velocity profile and related variables evidenced deterioration, showing changes in blood lactate concentration, maximum load at zero velocity, average velocity during the third trial, and stroke rate.
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