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1.
Sports Med Health Sci ; 6(2): 111-122, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38708326

RESUMO

There is a recent and growing interest in assessing differential responders to resistance training (RT) for diverse outcomes. Thus, the individual ability to respond to an intervention for a specific measurement, called responsiveness, remains to be better understood. Thus, the current study aimed to summarize the available information about the effects of RT on functional performance and muscle strength, power, and size in healthy adults, through the prevalence rate in different responsiveness classifications models. A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and was registered at the International Prospective Register of Systematic Reviews (PROSPERO, CRD42021265378). PubMed/MEDLINE, Scopus, and Embase databases were systematically searched in October 2023. A total of 13 studies were included, totaling 921 subjects. Only two studies presented a low risk of bias. Regarding the effectiveness of RT, the prevalence rate for non-responders ranged from 0% to 44% for muscle strength, from 0% to 84% for muscle size, and from 0% to 42% for functional performance, while for muscle power, the only study found showed a responsiveness rate of 37%. In conclusion, a wide range of differential responders is described for all variables investigated. However, the evidence summarized in this systematic review suggested some caution while interpreting the findings, since the body of evidence found seems to be incipient, and widely heterogeneous in methodological and statistical aspects.

2.
Int J Sports Med ; 45(5): 369-376, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38346688

RESUMO

This study aimed to investigate the impact of bar velocity during the eccentric phase on subsequent concentric performance in the young and elderly. Twelve elderly women (65.2+4.2 years) and 16 young women (23.1+2.1 years) were randomly assigned to four experimental conditions that combined high-velocity eccentric actions (HVECC; maximum velocity) and moderate-velocity eccentric actions (MVECC; 2.0 s), using 30% and 60% of their 1-repetition maximum (1RM) on the Smith machine bench press. Measurements of mean propulsive velocity (MPV), peak velocity (PV), and mean power (MP) were recorded. Two-way ANOVA with repeated measures was applied for each variable, when needed, the Bonferroni post hoc was used. Statistical significance was set at p<0.05, and effect size (ES) was established by Cohen's d z. The results demonstrated that elderly women showed improved performance in MPV (+10.0%; ES=- 0.58; p=0.009) and MP (+11.7%; ES=- 0.14; p=0.045) when utilizing HVECC at 30% 1RM only. Moreover, young women exhibited superior performance for both 30% and 60% 1RM when using HVECC for all variables analyzed (p<0.05). The HVECC appears to have an impact on the subsequent performance of the concentric phase, particularly when lighter loads (30% 1RM) are utilized, regardless of the age group.


Assuntos
Força Muscular , Levantamento de Peso , Humanos , Feminino , Idoso , Levantamento de Peso/fisiologia , Adulto Jovem , Força Muscular/fisiologia , Fatores Etários , Treinamento Resistido/métodos , Pessoa de Meia-Idade , Adulto , Músculo Esquelético/fisiologia , Desempenho Atlético/fisiologia
4.
PeerJ ; 11: e14764, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36743962

RESUMO

In combat sports, strikes or counter-strikes response time (RT) can be related to performance and sporting success. Moreover, training sessions are usually highly fatiguing, which is expected to impair basic skills, such as RT. Thus, this study aimed to investigate the effect of fatigue on punch and kick RTs of karate practitioners. Twelve individuals of both sexes from different levels (three yellow belts, three red belts, two orange belts, two green belts, one brown belt, and one black belt) were selected. Participants were aged 22 ± 3 years old, with a stature of 169.1 ± 6.5 cm, and a body mass of 65.5 ± 10 kg. Six visits were held with each participant. On the first 2 days, the RT of punches and kicks was measured by a validated smartphone app (TReaction). For the subsequent visits, a randomized incremental test for the upper or lower body was adopted as motor fatigue protocol, immediately followed by punches and kicks RT tests, also in random order. For induction of lower and upper body-specific muscle fatigue, the ITStriker app was used, which operates by emitting sound signals transmitted by a smartphone. One-way repeated measures ANOVA was performed, and significance was set at p ≤ 0.05. Regarding the mean punches RT, significant effects between situations for the upper (F(2,22) = 11.5; ω2 = 0.23; p < 0.001) and lower body (F(2,22) = 14.2; ω2 = 0.18; p < 0.001) fatigue protocols were found. The negative effect of the lower body fatigue protocol in punches RT was evident regardless of the order of the tests (punch RT first: Δ = 10.5%; t = 4.4; p < 0.001; d = 1.0; kick RT first: Δ = 11.4%; t = 4.8; p < 0.001; d = 1.1). Regarding mean kicks RT, significant effects were found between situations for the lower (F(2,22) = 16.6; ω2 = 0.27; p < 0.001) but not for the upper (F(2,22) = 2.3; ω2 = 0.02; p = 0.12) body fatigue protocols. Kick RTs were negatively affected by the lower body fatigue protocol regardless of the RT order applied (punch RT first: Δ = 7.5%; t = 3.0; p = 0.01; d = 0.8; kick RT first: Δ = 14.3%; t = 5.7; p < 0.001; d = 1.5). Upper body fatigue does not impair punch or kick RTs. Thus, it is concluded that the specificity of fatigue protocols and striking order should be considered while performing RT demanding techniques in karate practice. Specifically, lower body motor fatigue may impair both kicks and punches RT, which highlights the role of lower limbs in punches performance. Otherwise, upper body motor fatigue seems to induce impairments that are limited to the specific motor actions of this body segment.


Assuntos
Artes Marciais , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Atletas , Extremidade Inferior/fisiologia , Artes Marciais/fisiologia , Fadiga Muscular , Tempo de Reação
5.
Nutrients ; 15(2)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36678305

RESUMO

The plant extract guarana is known for its caffeine content and other bioactive ingredients, which purportedly may improve cognitive performance. Recent reviews have examined the effects of chronic supplementation of guarana in clinical populations; however, the acute effects of guarana on cognitive tasks, while of interest, have produced mixed results. Whether acute guarana ingestion improves human cognitive performance was assessed by performing a systematic review coupled with a meta-analysis. Eight placebo-controlled studies were identified and met the inclusion criteria providing data on 328 participants. The dose of guarana (37.5 to 500 mg) with reported caffeine content (4.3 to 100 mg) varied. Effect sizes (ESs) were calculated as the standardized mean difference and meta-analyses were completed using a random-effects model. The ESs for guarana averaged across a variety of cognitive measures and outcome variables were less than trivial (Hedge's g = 0.076, p = 0.14). Using a subgroup meta-analysis (Q = 12.9, p < 0.001), ESs indicating a faster response time for guarana vs. a placebo (g = 0.202, p = 0.005) differed from the accuracy measures (g = −0.077, p = 0.4) which were non-significant. For response time, guarana ingested in a capsule (g = 0.111) tended to differ (Q = 2.96, p = 0.085) compared to guarana when dissolved in liquid (g = 0.281). Meta-regression of the study ESs of overall cognitive task performance was not related to the guarana dose (R2 < 0.001) or to the time allowed prior to cognitive testing (R2 < 0.001). Acute guarana ingestion had a small effect on the response time (faster performance) during a variety of cognitive tasks without affecting the accuracy. Whether the changes were linked to the caffeine content or other bioavailable substances in guarana is unknown. Additional studies that directly compare matched doses of caffeine versus guarana are needed to understand its effects on cognitive performance.


Assuntos
Cafeína , Paullinia , Humanos , Cafeína/farmacologia , Extratos Vegetais/uso terapêutico , Tempo de Reação , Cognição
6.
Front Psychol ; 12: 656499, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34290647

RESUMO

Background: Mental fatigue is a psychobiological state caused by extended periods of cognitive effort, and evidence suggests that mentally fatigued athletes present impaired physical performance. Different ergogenic aids have been proposed to counteract the deleterious effects of mental fatigue, but whether brain stimulation can counteract mental fatigue is still unknown. This scenario is even more obscure considering the effects of these interventions (mental fatigue induction and brain stimulation) in a very experienced population consisting of master athletes. Method: Ten master swimmers (30 ± 6 years old and 14 ± 8 years of experience) participated in the study. They underwent four experimental conditions before an 800-m freestyle test: mental fatigue with brain stimulation; mental fatigue without brain stimulation; absence of mental fatigue with brain stimulation; and absence of mental fatigue and no brain stimulation. Mental fatigue was induced by a cognitively demanding Stroop Color Test, whereas stimulation was applied on the temporal cortex. After that, the athletes swan 800 m as fast as possible and provided their ratings of perceived exertion (RPE) every 200 m. Results: Mental fatigue was effectively induced, as evidenced by a greater fatigue perception and more errors in the last blocks of the cognitive task. Mental fatigue induction did not influence performance (time to complete the swimming trial) and RPE. Similarly, brain stimulation failed to change these two parameters, regardless of mental fatigue induction. Conclusion: The prolonged physical performance of experienced master athletes is not influenced, under the present conditions, by mental fatigue induction, cerebral stimulation, and their association.

7.
Motriz (Online) ; 27: e1021020031, 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1287356

RESUMO

Abstract Aim: The present study aimed to investigate the indicators of burnout, to determine whether playing position affects the perception of syndrome dimensions, and to identify burnout prevalence in professional football players. Methods: The participants were 100 professional football players (mean age 24.3 ± 4.6 years and meantime as a professional athlete of 9.2 ± 4.5 years) who were divided into three groups: 27 forwards, 34 midfielders, and 39 defenders. The Athlete Burnout Questionnaire (ABQ) and a sociodemographic questionnaire were applied. Results: The results show that a) the majority of athletes had low burnout indicators, b) there was no difference in the perception of burnout dimensions by playing position, and c) the prevalence of athletes with burnout, whether mild, moderate, or severe, was 13%. Conclusion: The variable of playing position was not a determinant of perception of burnout dimensions among the forwards, midfielders, and defenders. Nonetheless, the prevalence of burnout deserves attention, as the negative effects of this syndrome may exert impacts on health, well-being, and sports performance, making athletes more likely to abandon their sport.


Assuntos
Humanos , Futebol , Desempenho Atlético , Atletas/psicologia , Esgotamento Psicológico/epidemiologia
8.
Exp Gerontol ; 138: 111011, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32592830

RESUMO

OBJECTIVE: The aim of this study was to compare the effects of 12 weeks of traditional resistance training (TRT) or resistance training using Cluster-set (CS) on functional performance and physical fitness of postmenopausal and elderly women. METHODS: Participants (61.1 ± 4.9 years, body mass 64.5 ± 1.8 kg, height 155.7 ± 4.7 cm) were randomized to TRT (n = 35) or CS (n = 31). Anthropometric measures, muscle strength and power, gait speed, core stability, flexibility, and functional performance tests were performed before and after 12 weeks of training. The difference between protocols was the structure of rest intervals. The TRT group performed 120 s of rest between sets of 8 repetitions, while the CS performed 30 s of rest after every 2 repetitions. Two-way ANOVA with repeated measures was applied for each variable and, when needed, the Bonferroni post hoc was used. Statistical significance was set at p < 0.05. RESULTS: No group by time interaction was found for any variable. Regarding between-moment comparisons, there were significant improvements for 1 repetition maximum (RM) bench press (F = 104.6; ηp2 = 0.62; p < 0.001), 1RM leg press (F = 74.6; ηp2 = 0.53; p < 0.001), medicine ball throw (F = 64.0; ηp2 = 0.26; p < 0.001), standing long jump (F = 27.6; ηp2 = 0.30; p < 0.001), countermovement jump (F = 17.4; ηp2 = 0.21; p < 0.001), squat jump (F = 23.2; ηp2 = 0.26; p < 0.001), plank time (F = 31.6; ηp2 = 0.33; p < 0.001), 6 m walking test (F = 18.0; ηp2 = 0.22; p < 0.001), sit-to-stand test (F = 20.4; ηp2 = 0.24; p < 0.001), sit and reach test (F = 56.8; ηp2 = 0.47; p < 0.001) and 2 kg elbow curls (F = 15.9; ηp2 = 0.19; p < 0.001). CONCLUSION: Considering that both CS and TRT methods were equally effective to improve the physical fitness and functionality of elderly women, the decision of which protocol to use should be based on individual preferences and practical aspects.


Assuntos
Treinamento Resistido , Idoso , Feminino , Humanos , Força Muscular , Músculo Esquelético , Pós-Menopausa , Levantamento de Peso
9.
Front Nutr ; 7: 43, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32373621

RESUMO

Purpose: High-intensity activity is an important aspect of football performance during competitive match play. The aim of this study was to investigate the effect of beta-alanine supplementation throughout a short-duration intense football-specific training period prior to an international competition on measures of high-intensity running performance. Methods: Twenty-four elite international U20 female footballers (age 18 ± 1 y, height 1.67 ± 0.07 m, body mass 62.7 ± 7.4 kg) volunteered to perform the YoYo Intermittent Recovery Test Level 1 (YoYo IR1), the Running Anaerobic Sprint Test (RAST) and a 20-m maximal sprint test on two separate occasions, separated by 3 weeks of training and supplementation. Participants were randomly assigned to receive either 6.4 g·day-1 sustained-release beta-alanine (BA, N = 12) or an equivalent dose of maltodextrin (placebo, PL, N = 12) throughout a 3-week standardized training camp. Results: There was a main effect of group (P = 0.05) and time (P = 0.004) on YoYo IR1; overall values were lower in PL and distance covered was lower post- vs. pre-supplementation. There was no group × time interaction (P = 0.07). There was an effect of sprint number for RAST, but no further main effects and there were no effect for the 20-m sprint. Conclusions: Top-level female footballers involved in this intense 3-week training period prior to a competition worsened their high-intensity intermittent exercise capacity, and this negative result was not attenuated by a short-duration BA supplementation protocol throughout the same period. Further work is necessary to elucidate whether adapted training protocols and BA dosing regimens could lead to better results.

10.
Pensar prát. (Impr.) ; 22: 1-12, jan.-dez.2019.
Artigo em Português | LILACS | ID: biblio-1009797

RESUMO

Analisar diferenças nas habilidades de copingentre os sexos e o potencial esportivo de alu-nos-atletas de um colégio militar. Trezentos e oitenta e cinco alunos-atletas responderam o ACSI-28BR. O potencial esportivo foi avaliado pelos treinadores, sendo classificado como baixo e alto. Os meninos apresentaram maiores habilidades de copingdo que as meninas. Os meninos de alto potencial esportivo apresentaram maior confiança/motivação, treinabilidade e recurso total de coping, enquanto que as meninas de alto potencial apresentaram maior me-tas/preparação mental, concentração, confiança/motivação e recurso total de coping. Conclui-se que as habilidades psicológicas de copingsão maiores em alunos-atletas com alto potencial esportivo, variando entre meninos e meninas.


This study analyzes differences in the coping skills between sexes and the sporting potential of student-athletes of a military college. A total of 385student-athletes answered the ACSI-28BR. The sporting potential was evaluated by coaches, being classified as low and high. Males had higher coping skills than females. Males of high sporting potential showed higher confidence/motivation, trainability andtotal coping resources; while females with high potential had higher goals/mental preparation, concentration, confidence/motivation and total cop-ing resources. It is concluded that the coping psychological skills are higher in student-athletes with high sporting potential and vary between males and females.


Analizar diferencias en las habilidades de copingentre lossexos y el potencial deportivo de alumnos-atletas de un colegio militar. 385 alumnos-atletas respondieron el ACSI-28BR. El potencial deportivo fue evaluado por los entrenadores, siendo clasificado como bajo y alto. Los niños presentaron mayores habilidades de copingque las niñas. Los niños de alto poten-cial deportivo presentaron mayor confianza/motivación, capacitación y recurso total de co-ping; mientras que las niñas de alto potencial presentaron mayores metas / preparación men-tal, concentración, confianza/motivación y recurso total de coping. Se concluye que las habi-lidades psicológicas de copingson mayores en alumnos-atletas con alto potencial deportivo, variando entre niños y niñas.


Assuntos
Humanos , Masculino , Feminino , Estudantes , Adaptação Psicológica , Desempenho Atlético , Atletas , Estresse Fisiológico , Destreza Motora
11.
Rev. bras. cineantropom. desempenho hum ; 21: e59851, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1013444

RESUMO

Abstract Pacing strategy (PS) has a decisive impact on performance, especially on long-term races.The objective of this study is to characterize the PS used in swimming races of 800m and 1500m freestyle by the finalists of the Olympic trials of the United States, Europe and Brazil,and the Olympic finalists of 2016.Time partials of 63 athletes were analyzed using a decision tree and the CHAID method. The results showed that parabolic was adopted by swimmers of 800m, they start in first lap (29.67 ± 0.88 s), followed by an increase in time (+1.77 s) and a subsequent increase in time (32.04 ± 0.89 s), at the end, the swimmers presented an acceleration,reducing the average of the to 31.44 s. And by the free 1500m swimmers, divided into blocks with a faster average start (29.25 ± 1.15 s), half of the slowest race (30.30 ± 0.76 s), and a new acceleration at the end of the event (29.92 ± 1.12 s), both in the selective Olympic Games and the 2016 and 2016 Olympic final.The worst partials times were observed in the Brazilian Selective (Test Event) (31.11 ± 0.78 s). Medalist, despite presetting the same OS, can sustain a better rhythm throughout he 800m (31.52 ± 1.03 s) and 1500-m (29.80 ± 0.78). We conclude that parabolic PS is the optimal strategy adopted by swimmers of 800-m and 1500m freestyle.


Resumo A estratégia de prova (EP) tem impacto determinante no desempenho esportivo, principalmente em provas de longa duração. O objetivo foi caracterizar a EP utilizada em provas de natação de 800m e 1500m livre por finalistas das seletivas olímpicas dos Estados Unidos, Europa, Brasil e finalistas olímpicos de 2016. As parciais de tempo de 63 atletas foram analisadas por meio de árvore de decisão, utilizando o método CHAID. Os resultados mostraram que a EP parabólica foi adotada pelas nadadoras de 800m, com início (29.67 ± 0.88 s) seguido de um aumento de tempo (+1.77 s) e posterior novo aumento de tempo (32.04 ± 0.89 s), ao término as atletas apresentaram uma aceleração reduzindo a média para próximo à 31.44 s. E pelos atletas de 1500m livre, divididos em blocos com média inicias mais rápidas (29.25 ± 1.15 s), meio da prova mais lento (30.30 ± 0.76 s) e nova aceleração ao final da prova (29.92 ± 1.12s), tanto nas seletivas olímpicas quanto na final olímpica de 2016. Os piores tempos das parciais foram observados na seletiva olímpica do Brasil (evento teste) (31.11 ± 0.78 s). Atletas medalhistas, apesar de apresentarem a mesma EP, conseguem sustentar um melhor ritmo ao longo da prova de 800m (31.52 ± 1.03 s) e 1500-m (29.80 ± 0.78). Conclui-se que a EP parabólica é a estratégia ótima adotada pelos nadadores de 800m e 1500m.


Assuntos
Humanos , Masculino , Feminino , Natação , Análise e Desempenho de Tarefas
12.
Rev. bras. med. esporte ; 24(5): 347-351, Sept.-Oct. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-977835

RESUMO

INTRODUCTION: This study involved an analysis of the impact of mental fatigue on heart rate recovery (HRR), subjective measures of fatigue and intermittent running performance in handball players. OBJECTIVE: This study was aimed at (1) examining the effects of an induced state of mental fatigue on the aerobic performance of handball players, as measured by the Yo-Yo IR1 test, and (2) exploring possible changes in heart rate regulation through HRR analysis. METHODS: Twelve handball players (age: 17.50 ± 3.63 years; 5 ± 2.2 years of practice) undertook a Yo-Yo IR1 test on two occasions, separated by an interval of at least 72 hours. The Yo-Yo IR1 test was preceded by a 30-min treatment, consisting of the Stroop Color-Word Test, to induce mental fatigue. Participants in the control condition watched an emotionally neutral video. RESULTS: Higher ratings of mental fatigue and mental effort following the Stroop Test were observed for the experimental group. No differences in motivation were observed between conditions. Moreover, the induction of mental fatigue impaired running performance and led to a higher RPE during the Yo-Yo IR1 test. Notwithstanding, no changes in HRR or blood lactate levels were observed across conditions. CONCLUSION: Altogether, these results suggest that mental fatigue impairs intermittent running performance, without affecting HRR values. Level of Evidence III; Case-Control study.


INTRODUÇÃO: Este estudo envolveu uma análise do impacto da fadiga mental sobre a recuperação da frequência cardíaca (RFC), medidas subjetivas de fadiga e desempenho de corrida intermitente em jogadores de handebol. OBJETIVO: Este estudo visou (1) examinar os efeitos de um estado induzido de fadiga mental no desempenho aeróbico de jogadores de handebol, medido pelo teste Yo-Yo IR1 e (2) explorar possíveis alterações na regulação da frequência cardíaca através da análise da RFC. MÉTODOS: Doze jogadores de handebol (idade: 17,50 ± 3,63 anos, 5 ± 2,2 anos de prática) realizaram um teste Yo-Yo IR1 em duas ocasiões, com pelo menos 72 horas de intervalo. O teste Yo-Yo IR1 foi precedido por tratamento de 30 minutos que consistiu no teste Stroop Color-Word para induzir estado de fadiga mental. Os participantes na condição de controle assistiram a um vídeo emocionalmente neutro. RESULTADOS: Foram observadas taxas mais elevadas de fadiga mental e esforço mental após o teste Stroop para o grupo experimental. Não foram observadas diferenças na motivação entre as condições. Além disso, a indução de fadiga mental prejudicou o desempenho de corrida e levou a maior PSE durante o teste Yo-Yo IR1. Não obstante, não foram observadas alterações na RFC nem nas concentrações de lactato sanguíneo entre as condições. CONCLUSÃO: Em conjunto, esses resultados sugerem que a fadiga mental afeta o desempenho de corrida intermitente, sem alterar os valores de RFC. Nível de Evidência III; Estudo de caso-controle.


INTRODUCCIÓN: En el presente estudio se analizó el impacto de la fatiga mental en la recuperación de la frecuencia cardíaca (RFC), las medidas subjetivas de fatiga y el rendimiento intermitente en atletas de handball. OBJETIVO: los objetivos de este estudio fueron (1) examinar los efectos de un estado inducido de fatiga mental en el rendimiento aeróbico de atletas de handball, medida por el Yo-Yo IR1, y (2) explorar las posibles alteraciones en la regulación de la frecuencia cardíaca a través del análisis RFC. MÉTODOS: Doce atletas (edad: 17,50 ± 3,63 años, 5 ± 2,2 años de práctica) realizaron un test Yo-Yo IR1 en dos ocasiones, separados por un intervalo de al menos 72 horas. El test Yo-Yo IR1 fue precedido por un tratamiento de 30 minutos, consistente en el Stroop Color-Word Test, para inducir un estado de fatiga mental. Los participantes en la condición de control asistieron un video emocionalmente neutro. RESULTADOS: Se observaron altas percepciones de fatiga y esfuerzo mental después del test de Stroop para el grupo experimental. No se observaron diferencias de motivación entre las condiciones. Además, la inducción de fatiga mental perjudicó el desempeño de carrera y llevó a un mayor PSE durante el test Yo-Yo IR1. No obstante, no se observaron alteraciones en la RFC y en las concentraciones de lactato sanguíneo entre las condiciones. CONCLUSIÓN: En conjunto, estos resultados sugieren que la fatiga mental afecta el rendimiento intermitente de la carrera, sin alterar los valores de FCR. Nivel de Evidencia III; Estudio de caso-control.


Assuntos
Humanos , Masculino , Adulto Jovem , Esportes , Desempenho Atlético , Fadiga Mental/complicações , Atletas/psicologia , Corrida , Reprodutibilidade dos Testes , Tolerância ao Exercício , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia
13.
Pediatr Exerc Sci ; 30(2): 208-215, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29276857

RESUMO

PURPOSE: This study aimed to investigate the impact of mental fatigue on heart rate variability, subjective measures of fatigue, and swimming performance in young athletes. METHODS: Sixteen swimmers [15.45 (0.51) y old, 7.35 (2.20) y of swimming experience] performed a 1500-m time trial on 2 occasions separated by an interval of at least 72 hours. The 1500-m swimming was preceded by a 30-minute treatment that consisted of performing the Stroop Color and Word test to induce mental fatigue (experimental trial) or watching an emotionally neutral video (control trial). RESULTS: Participants reported higher ratings of mental fatigue and mental effort following the Stroop test when compared with the control trial, but no differences in motivation were observed. The induction of mental fatigue impaired swimming performance, as evidenced by a slower time (1.2%) to complete the 1500-m trial. No intertrial differences were identified for rating of perceived exertion during the swimming test or in heart rate variability after the Stroop and swimming tests. CONCLUSION: The results indicate that induction of mental fatigue impairs 1500-m swimming performance without changing heart rate variability.


Assuntos
Atletas/psicologia , Desempenho Atlético/psicologia , Fadiga Mental , Natação/psicologia , Adolescente , Estudos Cross-Over , Feminino , Frequência Cardíaca , Humanos , Masculino , Motivação , Teste de Stroop
14.
J. Phys. Educ. (Maringá) ; 29: e2942, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-954485

RESUMO

ABSTRACT The relative age effect (RAE) refers to the advantage of the athletes born on the first months of the sport selection period compared to those born months later during such a selection process, which tends to favor athletes who are in a more developed maturational stage or those who have more advanced physical development compared to their younger counterparts born in the same year. This advantage occurs mainly in sport whose physical characteristics are determinant for obtaining success, such as volleyball, which leads to the premature exclusion or dropout of potential talents from sport. This study aims at assessing the RAE presence in Brazilian men's and women's elite volleyball by analysing the number of athletes who were born in each trimester of the year and had been ranked to the main national Super Leagues. The results showed no effect related to the RAE in Brazilian women's elite volleyball, whereas there was a higher representation of male athletes born in the first trimester compared to the ones born on the 3rd and 4th trimesters. These results point to a need for better understanding the causes and consequences of RAE in Brazilian men's volleyball in order to avoid premature exclusion or dropout of potential talents, thus, enabling an even greater development of this sport in the country.


RESUMO O efeito da idade relativa (EIR) refere-se à vantagem de atletas nascidos nos primeiros meses do período de seleção em relação a seus pares nascidos em meses posteriores no processo de seleção esportivo, que tende a favorecer atletas que encontram-se em estágio maturacional ou de desenvolvimento físico mais avançados que o de seus colegas mais jovens nascidos no mesmo ano. Esse favorecimento ocorre principalmente em esportes cuja característica física é determinante para se obter sucesso, como o voleibol, acarretando na exclusão ou abandono prematuro da modalidade por parte de talentos em potencial. O objetivo do estudo foi avaliar a presença do EIR no voleibol brasileiro de elite feminino e masculino, pela análise da distribuição do número de atletas rankeados para as Superligas masculina e feminina nascidos em cada trimestres do ano. Os resultados indicaram não haver EIR no voleibol feminino brasileiro de elite, enquanto no masculino há uma maior representação de atletas nascidos no primeiro trimestre em comparação àqueles nascidos nos 3º e 4º trimestres. Esses resultados apontam para a necessidade de se entender melhor as causas e consequências do EIR no voleibol masculino brasileiro, afim de evitar a exclusão ou abandono precoce do esporte de possíveis talentos, permitindo um maior desenvolvimento da modalidade no país.


Assuntos
Desempenho Atlético , Voleibol , Grupos Etários
15.
Motriz (Online) ; 24(4): e101801, 2018. tab
Artigo em Inglês | LILACS | ID: biblio-976261

RESUMO

The aim of the present study was 1) compare the drop-out rates between athletes born in different trimesters of the competitive year from different sports and 2) identify the causes pointed by the dropped-out athletes born in different selection year trimesters to disengage from the competitive sports environment. Methods: Data from 966 athletes who left the competitive sports context were analyzed under the Relative Age Effect (RAE) theoretical framework during 3 consecutive seasons. The drop-out rate and the reason to quit the competitive environment were analyzed by a routine club questionnaire. Results: An expected reverse RAE on drop-out rates was identified, in which the early born athletes were overrepresented (p<0.001). Regarding the reasons to disengage from competitive sports environment, no reason emerged as the main cause to dropout between athletes born in different selection year trimester. Conclusion: It was concluded that despite the common assumption that personal psychological issues related to RAE in late born athletes are important factors influencing sports disengagement, the relationship between drop-out and RAE is more complex and multifactorial.(AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Esportes/psicologia , Atletas/psicologia , Estações do Ano , Fatores Etários
16.
Motriz rev. educ. fís. (Impr.) ; 21(2): 194-199, Apr-Jun/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-752449

RESUMO

The relative age effect, which is the advantage obtained by an athlete born closer to the beginning of the selection year, has been shown to be an important variable in the development of soccer players. This study aimed to evaluate the influence of the season of birth on the choice reaction time (CRT) of elite soccer athletes in the under 13 years of age category. Seventy-six athletes participated who were 13.36 ± 0.45 years old. The volunteers were tested with a CRT test, and the results were divided according to the semester of birth (S1 or S2). We conducted a t-test in order to compare the results between groups and a Pearson correlation analysis to verify the associations between variables. The results indicated no differences in reaction time (r= .033 and p = .772) or movement time (r = .0073 and p = .530). It was concluded that for this population, the season of birth does not influence the performance of the capabilities tested.


O efeito da idade relativa, que consiste na vantagem obtida pelo atleta nascido mais próximo ao início do ano de seleção, tem se mostrado uma variável importante para o processo de seleção de esportistas. Este estudo objetivou avaliar a influência da época de nascimento no tempo de reação de escolha de futebolistas presentes nas categorias de base (sub 13) de clubes profissionais futebol. Participaram 76 atletas com idade de 13,36 ± 0,45 anos. Os voluntários foram submetidos ao teste do TRE, e os resultados categorizados conforme o semestre de nascimento (S1 ou S2). Foi empregado o teste t para a comparação entre grupos, e análise de Correlação de Pearson para verificar a existência de associações entre as variáveis. Os resultados não indicaram diferenças entre os grupos no tempo de reação (r = 0,033 e p = 0,772) e no tempo de movimento (r = 0,0073 e p = 0,530). Concluiu-se que para essa população, a época de nascimento não influencia no desempenho dessa capacidade.


El efecto de la edad relativa, que consiste en el beneficio obtenido por el atleta nacido más cercano al inicio del año de selección ha sido una variable importante para el proceso de selección de los atletas. Este estudio tuvo como objetivo evaluarla influencia de la época de nacimiento en el tiempo de reacción de los jugadores presentes en los jóvenes (menores de 13) de los clubes de fútbol profesional. Participaron 76 atletas de edad 13,36 ± 0,45 años. Los voluntarios fueron sometidos a la prueba de la TRE, y se clasificaron de acuerdo con el semestre de nacimiento (S1 o S2). Se utilizó el "teste t" para la comparación entre los grupos, y el análisis de correlación de Pearson para verificar la existencia de asociaciones entre variables. Los resultados indicaron que no hubo diferencias entre los grupos en el tiempo de reacción (r = 0,033 e p = 0,772) y el Tiempo de Movimiento (r = 0,0073 e p = 0,530). Se concluyó que para esta población, la fecha de nacimiento no influye en el rendimiento de esta capacidad.


Assuntos
Humanos , Masculino , Adolescente , Distribuição por Idade , Aptidão , Atletas , Futebol
17.
Percept Mot Skills ; 114(2): 461-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22755451

RESUMO

Relative age effects refer to the effects of age differences among individuals who have been grouped together for a performance activity. This study aimed to investigate the relative age effect on Olympic Taekwondo athletes, in several Olympic Games, and in both sexes. The study sample consisted of 291 athletes who had competed in Atlanta, Sydney, and Beijing Olympic Games. The relative age effect was examined for the general distribution of athletes by quartile, for each of the individuals, and for male and female athletes. There were no discernable effects of relative age on Olympic Taekwondo athletes.


Assuntos
Atletas , Artes Marciais , Fatores Etários , Atletas/estatística & dados numéricos , Feminino , Humanos , Masculino , Artes Marciais/estatística & dados numéricos
18.
Rev. bras. ciênc. esporte ; 34(1): 41-51, jan.-mar. 2012. graf, tab
Artigo em Português | LILACS | ID: lil-624542

RESUMO

O Efeito da Idade Relativa, representado pela vantagem obtida pelo atleta nascido mais próximo ao início do ano de seleção, mostra-se uma variável significativa para a identificação de talentos em diversas modalidades. Objetivou-se avaliar o quartil de nascimento de atletas das categorias de base do futsal em Minas Gerais. Foram analisados 510 atletas inscritos em competições federadas em 2009. Para análise empregou-se o teste de qui-quadrado. Verificou-se diferenças significativas na distribuição dos quartis de nascimento em quatro das cinco categorias avaliadas, com predominâncias do primeiro e segundo quartis. Concluiu-se que o Efeito da Idade Relativa é um fator que pode influenciar a seleção de atletas nas categorias de base do futsal.


The effect of relative age, understood as the advantage obtained by athletes born in the beginning of the year of selection, is a significant variable for the development of talents in several modalities. Therefore, the objective is to assess the quartile of birth of athletes of the minor league categories of futsal in Minas Gerais. The sample was composed by 510 athletes enrolled in federated competitions in 2009. The chi-square test was used in this analysis. There were significant differences in the distribution of the quartiles of birth in four of the five categories assessed, with a predominance of the first and second quartiles. In conclusion, the effect of relative age is a factor which might influence the choice of futsal players in the base categories.


El efecto de la edad relativa, entendido como la ventaja obtenida por el atleta nacido em las primeras fechas del año de selección, se muestra una variable significativa para el desarrollo de talentos en distintas modalidades. Por esta se evaluó el cuartil de nacimiento de atletas de las categorias base del fútbol sala em Minas Gerais. La muestra estaba compuesta por 510 atletas inscritos en competiciones federadas en 2009. Para este análisis fue empleado el test de chi-cuadrado. Fueron encontradas diferencias significativas en la distribucíon de los cuartiles de nacimiento em cuatro de las cinco categorias evaluadas, con predomínio del primer y segundo. Se concluyó que el efecto de la edad relativa es un factor que puede influenciar em la selección de jugadores de fútbol sala em las categorias de base.

19.
Motriz rev. educ. fís. (Impr.) ; 18(1): 130-142, jan.-mar. 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-645722

RESUMO

Expertise é um campo de conhecimento que estuda as diferentes competências dos experts em seu campo de proficiências, como no esporte. Diversos modelos, a partir da perspectiva ambiental, avaliam fatores que influenciam no desenvolvimento expert. O objetivo deste trabalho foi verificar o contexto do desenvolvimento expert dos nadadores medalhistas olímpicos brasileiros. Oito nadadores que conquistaram, no mínimo, uma medalha em qualquer edição dos Jogos Olímpicos, foram os entrevistados. Realizou-se a transcrição das entrevistas e, posteriormente, uma análise qualitativa foi feita, por meio de mini-unidades (MUs). 218 MUs obedeceram à seguinte classificação: Início da carreira esportiva, presença dos treinadores, influência da família / amigos e prática deliberada. Concluiu-se, a partir dos resultados apresentados, que o contexto do desenvolvimento contribuiu de forma fundamental para a evolução dos atletas. As diversas realidades apontam que não existe necessariamente um padrão restrito de excelência.


Expertise as a field is one that studies the authenticity of the expert, meaning the skill or knowledge level he or she has in a certain field, such as athletics. Different models, from the ambient perspective, judge factors that influence the development of the expert. The aim of this study was to verify the context in which Brazilian swimmers develop, specifically those who have won an olympic medal. Eight swimmers who have won at least one medal in any category of the Olympic games were interviewed. The transcripts of the interviews were recorded, after which a qualitative analysis using Meaning – Units (MUs). 218 MUs were classified as follows: when the athlete's career began, the presence of coaches, the influence of family and friends, and deliberated practice. From the results, it can be concluded that the context of development contributed fundamentally to the evolution of the athletes. The diverse realities show that there is not a necessary pattern needed to restrict excellency.


Assuntos
Humanos , Masculino , Adulto , Natação , Pesquisa Qualitativa , Brasil
20.
Rev. bras. cineantropom. desempenho hum ; 14(5): 571-581, 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-649585

RESUMO

O Efeito da Idade Relativa que consiste na vantagem obtida pelo atleta nascido mais próximo ao início do ano de seleção, mostra-se uma variável importante para o desenvolvimento de talentos, particularmente, devido aos aspectos maturacionais. Objetivou-se analisar a distribuição das datas de nascimento dos atletas de futebol, participantes do mundial sub17, e verificar diferenças na estatura dos mesmos. Para isso, foram coletados junto ao site oficial da FIFA os dados referentes aos 1479 atletas inscritos nas últimas três competições (2007, 2009 e 2011). Posteriormente, os dados foram divididos pelo quartil da data de nascimento e também, pela zona de posição do campo. Para a comparação da representatividade proporcional de cada quartil da data de nascimento, foi utilizado o teste de qui-quadrado com correção de Bonferroni. Para a comparação das estaturas por quartil da data de nascimento e setor do campo, utilizou-se a análise de variância ANOVA em esquema fatorial 2x2. Também foi empregada uma análise de correlação de Spearman para a verificação de associação entre as variáveis. Diferenças foram encontradas na distribuição dos quartis da data de nascimento, com predomínio de atletas nascidos no primeiro e segundo quartis da data de nascimento, e nas estaturas dos atletas, sendo que os atletas nascidos no primeiro e segundo quartis da data de nascimento apresentaram estatura média superior. Concluiu-se que o efeito da idade relativa é um fator que pode influenciar a seleção de jogadores de futebol e que influencia a estatura (variável maturacional).


The Relative Age Effect, which consists in the advantage obtained by an athlete born closer to the beginning of the year selection, is shown as an important variable for the development of talent, particularly due to maturational aspects. The objective of this study was to analyze the distribution of the birth dates of the soccer players participating in the Under 17 World Championship, and verify the differences in their height. In order to do so, data referring to 1479 athletes registered in the last three competitions (2007, 2009 and 2011) was collected from the official FIFA site. Subsequently, the corresponding data was divided into birth date quartiles and also zone position of the field. For the comparison of proportional representativeness of each birth date quartile, it was used the chi-squared test with Bonferroni correction. The ANOVA factorial 2x2 was applied to compare the heights by birth date quartile and by zone position of the field. A Spearman correlation analysis was also used to verify the association between the variables. Differences were found in the distribution of birth date quartiles, with a predominance of athletes born in the first and second quartiles; and in the height of the athletes, having athletes who were born in the first and second quartiles a higher average height. It was concluded that the relative age effect is a factor that may influence the selection of soccer players and that influences the height (a maturational variable).

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