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1.
J Strength Cond Res ; 38(4): e160-e173, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38513184

RESUMO

ABSTRACT: Weldon, A, Cloak, R, Kirk, C, Ruddock, A, Langan-Evans, C, Detanico, D, Loturco, I, and Kons, R. Strength and conditioning (S&C) practices of judo athletes and S&C coaches: A survey-based investigation. J Strength Cond Res 38(4): e160-e173, 2024-The benefits of strength and conditioning (S&C) for improving judo performance and reducing injuries have been widely studied. However, the S&C practices used and perspectives held by those delivering S&C have yet to be elucidated. Therefore, this study investigated the S&C practices and perspectives of judokas and S&C coaches working within judo. Forty-two judokas and 9 S&C coaches completed an online survey comprising 6 sections: (a) written informed consent; (b) background information; (c) education, qualifications, and prescription; (d) views on S&C; (e) exercise selection; and (f) issues and improvements. Frequency analysis was used to report responses to fixed-response questions and thematic analysis for open-ended questions. Results indicated that S&C coaches were primarily responsible for delivering S&C programs (60%), and S&C information was predominantly sourced from S&C coaches (43%). Strength and conditioning was deemed very important for randori (78-88%), overall judo performance (67-79%), and judo fitness (62-78%). Similarly, S&C was considered very important for the development of speed and power (76-89%), strength (71-89%), and injury reduction (69-78%). Novel findings were also observed, such as integrating judo-specific training within S&C practice, which may be partly explained by more S&C coaches holding judo belts (67%) than S&C qualifications (11%). This study supports practitioners delivering S&C in judo by offering a base of information to critique or align with their existing S&C practices and perspectives. Furthermore, our results may help identify potential gaps between methods used, proposed guidelines, and actual practice, facilitating the development of research and education resources tailored to the current climate.


Assuntos
Artes Marciais , Treinamento Resistido , Humanos , Educação Física e Treinamento , Treinamento Resistido/métodos , Inquéritos e Questionários , Atletas
2.
Eur J Sport Sci ; 18(3): 431-440, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29355092

RESUMO

PURPOSE: To investigate the effect of sodium bicarbonate (NaHCO3) on performance and estimated energy system contribution during simulated taekwondo combat. METHODS: Nine taekwondo athletes completed two experimental sessions separated by at least 48 h. Athletes consumed 300 mg/kg body mass of NaHCO3 or placebo (CaCO3) 90 min before the combat simulation (three rounds of 2 min separated by 1 min passive recovery), in a double-blind, randomized, repeated-measures crossover design. All simulated combat was filmed to quantify the time spent fighting in each round. Lactate concentration [La-] and rating of perceived exertion (RPE) were measured before and after each round, whereas heart rate (HR) and the estimated contribution of the oxidative (WOXI), ATP (adenosine triphosphate)-phosphocreatine (PCr) (WPCR), and glycolytic (W[La-]) systems were calculated during the combat simulation. RESULTS: [La-] increased significantly after NaHCO3 ingestion, when compared with the placebo condition (+14%, P = 0.04, d = 3.70). NaHCO3 ingestion resulted in greater estimated glycolytic energy contribution in the first round when compared with the placebo condition (+31%, P = 0.01, d = 3.48). Total attack time was significantly greater after NaHCO3 when compared with placebo (+13%, P = 0.05, d = 1.15). WOXI, WPCR, VO2, HR and RPE were not different between conditions (P > 0.05). CONCLUSION: NaHCO3 ingestion was able to increase the contribution of glycolytic metabolism and, therefore, improve performance during simulated taekwondo combat.


Assuntos
Desempenho Atlético/fisiologia , Glicólise/efeitos dos fármacos , Artes Marciais/fisiologia , Bicarbonato de Sódio/farmacologia , Adolescente , Estudos Cross-Over , Método Duplo-Cego , Ingestão de Alimentos , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Bicarbonato de Sódio/administração & dosagem , Adulto Jovem
3.
J Strength Cond Res ; 31(3): 743-749, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27379958

RESUMO

Loturco, I, Nakamura, FY, Winckler, C, Bragança, JR, da Fonseca, RA, Filho, JM, Zaccani, WA, Kobal, R, Cal Abad, CC, Kitamura, K, Pereira, LA, and Franchini, E. Strength-power performance of visually impaired paralympic and olympic judo athletes from the brazilian national team: a comparative study. J Strength Cond Res 31(3): 743-749, 2017-The aim of this study was to compare the muscle power and maximal isometric strength capacities of Olympic and visually impaired Paralympic judo athletes. Twenty-eight elite judo athletes (7 men and 7 women per group) from the permanent Brazilian National Paralympic and Olympic teams took part in this study. After a specific warm-up, the athletes performed loaded jump squat (JS), bench press (BP), and standing barbell row (SBR) exercises to determine their values of maximum mean propulsive power (MPP) in these respective exercises. The maximal isometric strength (MIS) was also determined for both upper and lower limbs, through the use of BP and half-squat (HS) exercises. Finally, the jumping ability was assessed using unloaded squat jump (SJ). The magnitude-based inference was used to compare the groups. The Olympic judo athletes presented a likely higher SJ height than the Paralympic athletes. The Olympic group presented almost certainly higher MPP in the loaded JS and in the SBR exercises and likely higher MPP in the BP exercise. Importantly, in the MIS assessments the differences between groups in the HS and BP exercises were rated as unclear. In conclusion, our results showed that both Olympic and Paralympic judo athletes present similar levels of maximal isometric strength, but muscle power performance is superior in Olympic athletes.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Treinamento Resistido/métodos , Pessoas com Deficiência Visual , Adolescente , Adulto , Brasil , Estudos Transversais , Feminino , Humanos , Contração Isométrica/fisiologia , Extremidade Inferior/fisiologia , Masculino , Artes Marciais/fisiologia , Adulto Jovem
4.
Int J Sports Physiol Perform ; 11(6): 833-837, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26694761

RESUMO

PURPOSE: To quantify the training loads reported by karate athletes of the Brazilian national team in the week immediately before their participation in the 2015 Pan American Games. METHODS: Eleven elite karate athletes (7 men and 4 women, 24.42 ± 3.75 y, 1.70 ± 0.09 m, 69.6 ± 13.2 kg) from the Brazilian national team took part in this study. Session rating of perceived exertion (s-RPE) was quantified in all training sessions. Moreover, resting heart-rate variability (HRV), as analyzed through the natural log of the root-mean-square difference of successive normal RR intervals (lnRMSSD), and countermovement-jump (CMJ) performance before and after 8 training sessions were assessed throughout the week. The differences based on magnitudes were calculated comparing pre- and posttraining session, as well as measures performed every morning during the week. RESULTS: The weekly s-RPE was 2608.5 ± 431.2 a.u. The lnRMSSD was very likely higher on Monday than on the following days of the week, remaining stable during this period. CMJ height did not change during the week. Almost certain differences were observed in lnRMSSD pre- and posttraining session, while CMJ height did not change. CONCLUSIONS: The national karate-team athletes did not present signs of fatigue accumulation, as indicated by relatively steady HRV and unchanged CMJ during the week, as planned by the coaches for precompetition technical and tactical refinement.


Assuntos
Desempenho Atlético/fisiologia , Sistema Nervoso Autônomo/fisiologia , Artes Marciais/fisiologia , Força Muscular/fisiologia , Esforço Físico , Adulto , Fenômenos Biomecânicos , Brasil , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Adulto Jovem
5.
PLoS One ; 10(11): e0142078, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26539982

RESUMO

OBJECTIVES: The aim of this study was to evaluate the effect of caffeine ingestion on performance and estimated energy system contribution during simulated taekwondo combat and on post-exercise parasympathetic reactivation. METHODS: Ten taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed a capsule containing either caffeine (5 mg∙kg-1) or placebo (cellulose) one hour before the combat simulation (3 rounds of 2 min separated by 1 min passive recovery), in a double-blind, randomized, repeated-measures crossover design. All simulated combat was filmed to quantify the time spent fighting in each round. Lactate concentration and rating of perceived exertion were measured before and after each round, while heart rate (HR) and the estimated contribution of the oxidative (WAER), ATP-PCr (WPCR), and glycolytic (W[La-]) systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was evaluated through 1) taking absolute difference between the final HR observed at the end of third round and the HR recorded 60-s after (HRR60s), 2) taking the time constant of HR decay obtained by fitting the 6-min post-exercise HRR into a first-order exponential decay curve (HRRτ), or by 3) analyzing the first 30-s via logarithmic regression analysis (T30). RESULTS: Caffeine ingestion increased estimated glycolytic energy contribution in relation to placebo (12.5 ± 1.7 kJ and 8.9 ± 1.2 kJ, P = 0.04). However, caffeine did not improve performance as measured by attack number (CAF: 26. 7 ± 1.9; PLA: 27.3 ± 2.1, P = 0.48) or attack time (CAF: 33.8 ± 1.9 s; PLA: 36.6 ± 4.5 s, P = 0.58). Similarly, RPE (CAF: 11.7 ± 0.4 a.u.; PLA: 11.5 ± 0.3 a.u., P = 0.62), HR (CAF: 170 ± 3.5 bpm; PLA: 174.2 bpm, P = 0.12), oxidative (CAF: 109.3 ± 4.5 kJ; PLA: 107.9 kJ, P = 0.61) and ATP-PCr energy contributions (CAF: 45.3 ± 3.4 kJ; PLA: 46.8 ± 3.6 kJ, P = 0.72) during the combat simulation were unaffected. Furthermore, T30 (CAF: 869.1 ± 323.2 s; PLA: 735.5 ± 232.2 s, P = 0.58), HRR60s (CAF: 34 ± 8 bpm; PLA: 38 ± 9 bpm, P = 0.44), HRRτ (CAF: 182.9 ± 40.5 s, PLA: 160.3 ± 62.2 s, P = 0.23) and HRRamp (CAF: 70.2 ± 17.4 bpm; PLA: 79.2 ± 17.4 bpm, P = 0.16) were not affected by caffeine ingestion. CONCLUSIONS: Caffeine ingestion increased the estimated glycolytic contribution during taekwondo combat simulation, but this did not result in any changes in performance, perceived exertion or parasympathetic reactivation.


Assuntos
Desempenho Atlético/fisiologia , Cafeína/farmacologia , Glicólise/efeitos dos fármacos , Artes Marciais/fisiologia , Sistema Nervoso Parassimpático/efeitos dos fármacos , Adulto , Atletas , Estudos Cross-Over , Método Duplo-Cego , Exercício Físico/fisiologia , Teste de Esforço/efeitos dos fármacos , Glicólise/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/metabolismo , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Sistema Nervoso Parassimpático/fisiologia , Adulto Jovem
6.
J Strength Cond Res ; 28(7): 1826-32, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24276310

RESUMO

This study investigated the relationship between punching acceleration and selected strength and power variables in 19 professional karate athletes from the Brazilian National Team (9 men and 10 women; age, 23 ± 3 years; height, 1.71 ± 0.09 m; and body mass [BM], 67.34 ± 13.44 kg). Punching acceleration was assessed under 4 different conditions in a randomized order: (a) fixed distance aiming to attain maximum speed (FS), (b) fixed distance aiming to attain maximum impact (FI), (c) self-selected distance aiming to attain maximum speed, and (d) self-selected distance aiming to attain maximum impact. The selected strength and power variables were as follows: maximal dynamic strength in bench press and squat-machine, squat and countermovement jump height, mean propulsive power in bench throw and jump squat, and mean propulsive velocity in jump squat with 40% of BM. Upper- and lower-body power and maximal dynamic strength variables were positively correlated to punch acceleration in all conditions. Multiple regression analysis also revealed predictive variables: relative mean propulsive power in squat jump (W·kg-1), and maximal dynamic strength 1 repetition maximum in both bench press and squat-machine exercises. An impact-oriented instruction and a self-selected distance to start the movement seem to be crucial to reach the highest acceleration during punching execution. This investigation, while demonstrating strong correlations between punching acceleration and strength-power variables, also provides important information for coaches, especially for designing better training strategies to improve punching speed.


Assuntos
Aceleração , Artes Marciais/fisiologia , Movimento/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Desempenho Atlético/fisiologia , Teste de Esforço , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Análise de Regressão , Fatores Sexuais , Adulto Jovem
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