Central and peripheral fatigue during and after exhaustive exercises in front crawl: relationship with swim technique parameters

• Grant number: 12/17535-1
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2013
• End date: December 31, 2014
• Field of knowledge: Health Sciences - Physical Education
• Principal Investigator: Camila Coelho Greco
• Grantee: Camila Coelho Greco
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil

Abstract

Fatigue is associated with loss of force and work capacity. In swimmers, the swim technique impairment has been attributed to the loss of propulsive force throughout competitions and constant-speed exercises performed to exhaustion. Thus, the objective of this study is to verify the relationship between fatigue and the change in swim technique in an exhaustive exercise in front crawl. Twenty middle- and long-distance swimmers will perform the following protocols: 1) Determination of anthropometric measurements and familiarization to the isokinetic dynamometer; 2) Maximal 400-m to determine aerobic performance (V400), in a 25-m swimming pool; 3) Strength tests in an isokinetic dynamometer, to determine peak isometric torque (PTI), performed before and immediately after constant-speed tests at 100%V400, performed to exhaustion to determine the time limit (tlim), and two tests with duration of 40%tlim and 60%tlim. The variables stroke frequency (SF), stroke length (SL), stroke index (SI), stroke phases A, B, C and D and index of coordination (IdC) will be determined in all swim tests, with two cameras. The normality of data will be checked using Shapiro-Wilk test. For the analysis of the exhaustive exercises on the neuromuscular and swim technique variables, ANOVA TWO WAY (exercise vs. moment of the exercise), complemented by Tukey test will be performed. For variables that not present normal distribution, the effect of exhaustive exercise will be analyzed by Friedman test, complemented by Wilcoxon test. The correlation between neuromuscular variables and swim technique variables will be performed by Pearson correlation test. The correlation between the variation of the parameters before and after the exhaustive exercises will be performed by Spearman correlation test. The significance level will be set at p d 0.05. (AU)