Cycle of body mass reduction-recovery, inhibitory control, and performance of judo athletes

• Grant number: 24/18847-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: December 01, 2024
• End date: March 31, 2026
• Field of knowledge: Health Sciences - Physical Education
• Principal Investigator: Emerson Franchini
• Grantee: Danilo França Conceição dos Santos
• Host Institution: Escola de Educação Física e Esporte (EEFE). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 24/08930-1 - Cycle of body mass reduction-recovery, inhibitory control, and performance of judo athletes, AP.R

Abstract

In combat sports, such as judo, athletes compete in different weight categories. This procedure is adopted sothat athletes fight opponents with similar physical characteristics. Despite this, athletes frequently engage inrapid weight loss (RWL) to gain an advantage over lighter opponents. Studies evaluating the effect of RWL onperformance present controversial results. However, few studies have been conducted after the rule change thataltered the weigh-in format, moving the official weigh-in to the day before the competition and a new weigh-infor some athletes (randomly selected) on the morning of the competition. Additionally, studies investigating theeffects of RWL on competitive performance have only used the final competition result, disregarding aspects(e.g., technical-tactical aspects) that could affect competitive performance. Therefore, the objective of this studyis to evaluate the prevalence, magnitude, and methods related to RWL and its relationship with cognitive andcompetitive performance. For this purpose, the work is divided into two distinct studies: Study 1 - This study willinvolve 2,331 athletes from junior and senior categories, of all competitive levels, who have been active for atleast one year. To evaluate the prevalence of RWL and the magnitude of weight loss typically experienced byathletes, a rapid weight loss questionnaire (RWLQ), already validated in Brazil, will be used. The questionnairewill be made available for self-completion on the Google Forms online platform. Additionally, athletes atcompetitions will be contacted and invited to complete the questionnaire. Descriptive analyses (mean, standarddeviation, and frequency) will be calculated for all variables. To compare the scores obtained on the questionnaireby the athletes, the Mann-Whitney U test and one-way analysis of variance will be used; Study 2 - The finalsample size will be determined after conducting a pilot plan with 8 state-level athletes, of both sexes, adults; those with these characteristics will be used in the final study. After the agreement and characterization of thevolunteers, they will be evaluated in the following situations: in a condition without RWL (10 days before thecompetition), athletes will be evaluated regarding self-control, cognitive performance, and will keep a food diaryfor 3 days. Before (10 days), during (competition week), and after the RWL period (official weigh-in), athletes willbe evaluated regarding self-control, cognitive performance, and will keep a food diary for 3 days, in addition torecording body mass at the official weigh-in, on the morning of the competition, and 1 hour before the firstmatch. The athletes' matches will be recorded throughout the competition for subsequent temporal and technicalanalyses. The Shapiro-Wilk and Mauchly tests will be used to test the normality and sphericity of the data,respectively. Descriptive analysis will be performed using absolute values (kg) and percentages, with calculationsof means, standard deviations, and 95% confidence intervals. Two-factor analysis of variance (group - medalistsand non-medalists - and moments) with repeated measures on the second factor will be used to compare thereduction and recovery of body mass between moments, as well as cognitive task performance among athleteswith different results. To verify if there is a correlation between the magnitude of body mass recovery andexplanatory performance variables, Pearson's correlation test will be used. Logistic regression will be used todetermine the association between winning the competition and the adoption of RWL methods. Cohen's effectsize (d) and partial eta squared will be reported for all tests when appropriate. The significance level adopted forall analyses will be 5%.