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How to Evaluate Ergogenic Aid ClaimsHoutkooper, Linda, Maurer, Jaclyn, Mullins, Veronica 02 1900 (has links)
3 pp. / discontinued 3/4/11 / Nutrition misinformation, myths, fraud, and quackery can prevent athletes from attaining optimal performance. This publication provides a list of criteria to evaluate the myriad of information in the media surrounding the athlete and ergogenic aids.
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CAFFEINE TIMING AND CYCLING PERFORMANCERyan, Edward J. 26 August 2011 (has links)
No description available.
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Avaliação eletromiografica e força de musculos do membro superior em individuos submetidos a suplementação de creatina / Strenght and elctromyographic evaluation of upper limb muscles in men undergoing creatine supplementationSilva, Daniela Cristina de Oliveira 13 August 2018 (has links)
Orientador: Fausto Berzin / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-13T18:13:58Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: A eletromiografia de superfície é um instrumento potencial para estudos anatômicos, clínicos e cinesiológicos da atividade elétrica muscular e tem sido aplicada para identificar padrões de ativação muscular associados com força e fadiga muscular. A suplementação de creatina tem sido utilizada para aumentar a força e eficiência muscular, bem como diminuir o início da fadiga muscular. Assim, o objetivo deste trabalho foi analisar a atividade eletromiográfica e força dos músculos bíceps braquial (BB), braquiorradial (BR) e flexor ulnar do carpo (FUC) em indivíduos submetidos à suplementação aguda e crônica de creatina. Vinte indivíduos do sexo masculino, idade 18-35 anos, treinados em exercícios resistidos (musculação), foram selecionados para este estudo duplo-cego, randomizado, placebo-controlado. Os voluntários foram divididos em dois grupos: creatina (5 g de creatina e 5 g de maltodextrina, n=10) e placebo (5 g de celulose e 5 g de maltodextrina, n=10). A suplementação foi ingerida quatro vezes ao dia durante os primeiros 7 dias, e uma vez ao dia durante os 49 dias subsequentes. Cada voluntário realizou contração voluntária isométrica máxima (CVIM) de flexão do antebraço e com 30% e 60% da CVIM, antes e após 7 e 56 dias de suplementação. Os sinais eletromiográficos foram captados utilizando eletrodos de superfície passivos conectados a um pré-amplificador, registrados em um eletromiógrafo computadorizado, e analisados pelo software Myosystem-Br1. Uma célula de carga foi empregada para medir a força isométrica máxima durante os testes. Os dados eletromiográficos foram calculados pelos valores de amplitude (RMS - root mean square) e freqüência mediana (FM), e analisados por meio de curva de regressão linear, gerando coeficientes angulares de RMS e FM que foram considerados índices de eficiência e fadiga muscular, respectivamente. Os resultados mostraram que o grupo creatina exibiu aumento da força somente após 56 dias de suplementação (p < 0,05), enquanto nenhuma diferença foi encontrada no grupo placebo. Os músculos BB e BR mostraram decréscimo nos valores de coeficientes angulares de RMS após 7 e 56 dias de suplementação de creatina com 60% da CVIM (p < 0,05). Nenhuma diferença significante foi observada nos valores de coeficientes angulares de FM entre os tempos de suplementação para todos os músculos, em ambos os grupos e cargas. Assim, pode ser concluído que a suplementação crônica de creatina aumenta a força isométrica de flexão do antebraço. Além disso, tanto a suplementação aguda como a crônica de creatina melhoram a eficiência muscular de BB e BR apenas com cargas maiores, porém não tem efeito benéfico na redução da fadiga muscular de BB, BR e FUC, em qualquer intensidade de carga / Abstract: Surface electromyography is a potential tool for anatomic, clinic and kinesiologic studies of muscle electric activity and it has been employed to identify muscular activation levels associated with force and muscular fatigue. Creatine supplementation has been used to augment the strength and muscular efficiency as well to decrease the onset of muscular fatigue. This study aimed to analyze the force and electromyographic activity of biceps brachii (BB), brachioradialis (BR) and flexor carpi ulnaris (FCU) muscles in subjects submitted to acute and chronic creatine supplementation. Twenty resistance-trained male volunteers, aged 18 to 35 years, were selected for this double-blind, controlled-placebo, randomized study. Volunteers were placed into two groups: creatine (5 g creatine and 5 g maltodextrine, n=10) and placebo (5 g cellulose and 5g maltodextrine, n=10). Oral supplementation was given 4 times per day during the first 7days and once a day in the 49 subsequent days. Volunteers performed maximum isometric voluntary contraction (MIVC) of forearm flexion and with 30% and 60% MIVC, before and after 7 and 56 days of supplementation. Electromyographic signs were captured using passive surface electrodes joined to a pre-amplifier, recorded in a computer-connected electromyography and analyzed by the Myosystem-Br1 software. A load cell was used to measure the maximum isometric strength during the tests. Electromyographic data were calculated by values of amplitude (RMS - root mean square) and median frequency (MF) and analyzed by linear regression curve, generating RMS and MF slopes that were considered muscular efficiency and fatigue indices, respectively. Results showed that creatine group exhibited an increase of strength only after 56 days of supplementation (p < 0.05), while no significant difference was found in placebo group. BB and BR muscles showed a decrease of RMS slopes after 7 and 56 days of creatine supplementation with 60% MIVC (p < 0.05). No significant difference was observed in MF slopes among times of supplementation for all muscles in both loads and groups. It can be concluded that the chronic creatine supplementation increases the isometric strength of forearm flexion. Also, both acute and chronic creatine supplementation improve the BB and BR muscular efficiency only with high loads, but do not have beneficial effect on reducing muscular fatigue of BB, BR and FCU, whichever the load / Doutorado / Anatomia / Doutor em Biologia Buco-Dental
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Pre-exercise carbohydrate supplementation effects on intermittent critical velocity, anaerobic running capacity, and critical rest intervalsBialecki, Adam 29 August 2017 (has links)
No description available.
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The effects of sodium bicarbonate (NaHCO3) on whole body and isolated skeletal muscle performanceHiggins, M. January 2013 (has links)
This thesis examined four key areas considered to contribute to why the efficacy of sodium bicarbonate (NaHCO3) as an ergogenic aid remains equivocal. Firstly, familiarisation to and test re-test reliability of continuous constant load cycling to exhaustion (TLIM) at 110% peak power output (WPEAK) were investigated. Results indicated two trials are required before participants become fully familiarised and reliable data are obtained and that daily biological variation was 6 ± 11% (16 ± 28 s). The primary aim of study two was to determine the most appropriate exercise intensity for future studies in this thesis. A secondary aim was to elucidate why certain participants appear to respond to NaHCO3 ingestion and others do not (Price and Simons 2010, Saunders et al. 2011). Therefore, we evaluated cycling TLIM at 100%, 110% and 120% WPEAK in the same participants. NaHCO3 ingestion increased TLIM by 17% compared to placebo (PLA) at 100% WPEAK. This was due, at least in part, to attenuated localised ratings of perceived exertion (RPEL). No difference in group level data was observed between treatments at 110% WPEAK or 120% WPEAK although there was marked inter and intra individual variance. Thirdly, in order to evaluate the efficacy of NaHCO3 at a tissue level we examined the effects of NaHCO3 on dynamic isolated muscle performance undergoing cyclical length changes. Acute power output (PO) was on average 7.0% greater for NaHCO3 treated extensor digitorum longus (EDL) muscles and 3.6% greater for NaHCO3 treated soleus (SOL) muscles compared to control (CON). Increases in PO were due to greater force production throughout shortening. Treatment of EDL and SOL did not alter the pattern of fatigue at a group level although similar to study 2 there was marked inter individual variation. Finally, to determine the effects of training status we evaluated the effects of 6 weeks high-intensity cycling training on the efficacy of NaHCO3. Overall, pre-training TLIM was 10% greater with NaHCO3 compared to PLA with a benefit to harm odds ratio of 571. Overall, post-training TLIM was 6% greater with NaHCO3 compared to PLA with a benefit to harm odds ratio of 17. Similar to studies 2 and 3 individual variation was observed. Based on daily biological variation for TLIM of 6% (as determined in study 1) and a recommended benefit to harm odds ratio threshold of > 66, NaHCO3 improved TLIM before training only. We concluded that 6 weeks high-intensity cycling training reduces the effectiveness of NaHCO3 in previously non-cycling trained males. The change in efficacy is likely due to, at least in part, training induced changes in intracellular buffering capacity. In summary, NaHCO3 is an effective ergogenic aid for TLIM cycling at 100% WPEAK in non-cycling trained males. This is due, at least in part, to attenuated localised ratings of perceived exertion (RPEL). In contrast, 6-weeks high-intensity cycling training reduces the efficacy of NaHCO3 for TLIM cycling at 100% WPEAK in previously non-cycling trained males. The change in efficacy is likely due to, at least in part, training induced changes in intracellular buffering capacity. At a skeletal muscle level, NaHCO3 increases acute PO in both predominantly fast (EDL) and predominantly slow (SOL) twitch muscle fibres, due to greater force production throughout shortening.
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The application of respiratory muscle training to competitive rowingGriffiths, Lisa Ann January 2010 (has links)
Respiratory muscle training (RMT) has been shown to improve exercise tolerance during a wide range of exercise modalities and durations of activity (McConnell & Romer, 2004b). However, there is a limited amount of research characterising the influence of RMT in specific athletic populations, or examining any sport-specific factors that may influence the benefits of RMT. Hence, the purpose of this dissertation was to evaluate the application of RMT in competitive rowers and to explore methods of optimising this to rowing. Results: Inspiratory muscle training (IMT) increased inspiratory muscle strength (~20-29%; p < 0.05) and attenuated inspiratory muscle fatigue (~8-28%; p < 0.05) during time trial performance in club-level and elite rowers. However, only in the club-level oarsmen was IMT associated with a measurable improvement in rowing performance (2.7% increase in mean power; p < 0.05). Expiratory muscle training (EMT) provided no ergogenic effect, and concurrent EMT and IMT did not enhance performance above that seen with IMT alone. IMT loads performed at 60-70% of maximal inspiratory mouth pressure (PImax) were equivalent to the widely used 30 repetition maximum, which is higher than reported for non-rowers (Caine & McConnell, 1998a); further, a load of 60% PImax was sufficient to activate the inspiratory muscle metaboreflex, as evidenced by a time-dependent rise in heart rate (70.1 ± 13.2 to 98.0 ± 22.8 bpm; p < 0.05) and mean arterial blood pressure (92.4 ± 8.5 to 99.7 ± 10.1 mmHg; p < 0.05). Higher and lower inspiratory loads did not activate the metaboreflex. Assessments of flow, pressure and volume in rowing relevant postures revealed no significant impairments, but optimal function occurred in the most upright postures. Conclusions: These data support the application of IMT, but not EMT, in elite and sub-elite rowers, and suggest that a load of 60-70% of PImax provides metaboreflex activation during loading. Further, the data do not support a requirement to undertake IMT in rowing relevant postures.
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Efeito agudo da suplementação de capsaicina no desempenho de corredores em teste contra-relógio de 10 km /Filitto, Ana Elisa von Ah Morano January 2020 (has links)
Orientador: Fábio Santos Lira / Resumo: O objetivo deste estudo randomizado duplo-cego controlado por placebo foi investigar o efeito agudo da suplementação análoga de capsaicina (CAP) na corrida, em teste contra-relógio de 10-km, sobre o desempenho fisiológico e variáveis perceptivas de esforço em atletas amadores. Vinte e um participantes (idade = 29,3 ± 5,4 anos; peso = 74,2 ± 11,3 kg; altura = 176 ± 0,0 cm), completaram dois testes de 10-km na condição CAP ou placebo. Foram consumidas duas cápsulas de CAP (12 mg) ou de placebo, 45 minutos antes e imediatamente no início dos testes. Entre as condições CAP e placebo, não houve diferença significativa no desempenho dos participantes em relação às variáveis fisiológicas e perceptivas avaliadas no teste de corrida de 10-km (p> 0,05). Portanto, a suplementação de CAP não melhorou o desempenho de atletas amadores na corrida em teste contra-relógio de 10-km. / Abstract: The aim of this randomized, double-blind, placebo-controlled study was to investigate the acute effect of analog capsaicin supplementation (CAP), in a 10-km timetrial running test, on the physiological performance and perceptual responses of amateur athletes. Twenty-one participants (age = 29.3 ± 5.4 years; weight = 74.2 ± 11.3 kg; height = 176 ± 0.0 cm), completed two 10-km tests in the CAP or placebo condition. Two capsules of CAP (12 mg) or placebo were consumed 45 minutes before and immediately at the beginning of the trials. Between CAP and placebo conditions, there was no significant difference in the physiological performance or perceptual responses of the participants in the 10-km running test (p> 0.05). Therefore, CAP supplementation did not improve the performance of amateur athletes in the 10-km time-trial running test. / Mestre
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Papel da atividade muscular sobre a regulação do conteúdo de carnosina em resposta à suplementação de beta-alanina: um estudo em atletas com lesão medular / Role of muscle activity on the regulation of carnosine concentration in response to beta-alanine supplementation: a study in athletes with spinal cord injuryNemezio, Kleiner Márcio de Andrade 07 February 2019 (has links)
INTRODUÇÃO: Atualmente ainda não está claro se a atividade muscular e o treinamento físico afetam a síntese de carnosina muscular (Mcar) em resposta à suplementação de beta-alanina. OBJETIVO: verificar o impacto da atividade e inatividade muscular sobre o conteúdo de carnosina muscular (Mcarn) e sobre o aumento de Mcarn em resposta à suplementação de beta-alanina e, adicionalmente, verificar seu efeito sobra a capacidade de realizar esforços de alta intensidade. METHODS: Dezesseis homens treinados com lesão medular (LM) (escala ASIA: AIS A ou AIS B) foram divididos em 2 grupos: beta-alanina (BA) (N = 11) e placebo (PL) (N = 5). Amostras de biópsias musculares foram obtidas do músculo vasto lateral inativo e do deltoide ativo, antes e após 28 dias de suplementação com beta-alanina (6.4 g.dia-1). Teste t independente foi aplicado para comparar a Mcar basal e a variação absoluta (PÓS - PRÉ) entre os músculos vasto lateral e deltoide. Um teste supramáximo de carga constante até a exaustão e um teste de Wingate de série única foram aplicados para verificar a capacidade de realizar esforços de alta intensidade. Análises por Modelo Misto foram aplicadas para comparar a Mcar, o tempo até a exaustão e os valores de potência pico intra e entre sujeitos. RESULTADOS: (média ± desvio padrão): a concentração basal de Mcar no vasto lateral foi significativamente maior que no deltoide (32,0 ± 12 vs. 20,5 ± 6,1 mmol.kg-1 de músculo seco; p = 0,02). As variações absolutas na Mcar foram significativamente maiores no grupo BA em comparação com o PL, tanto para o vasto lateral (BA: 17,6 ± 10,4 mmol.kg-1 de músculo seco; PL: 2,5 ± 2,3 mmol.kg-1 de músculo seco; p = 0,002) como para o deltoide (BA: 15,7 ± 6,8 mmol.kg-1 de músculo seco; PL: 1,4 ± 2,7 mmol.kg-1 de músculo seco; p <0,001). As variações absolutas verificadas no vasto lateral e deltoide não foram diferentes entre si (vasto lateral: 17,6 ± 10,4; deltóide: 15,7 ± 6,8 mmol.kg-1 do músculo seco; p = 0,6). Não houve efeito da suplementação sobre o tempo até exaustão e potência pico. CONCLUSÃO: a inatividade muscular crônica ocasionada por lesão medular, não afeta a Mcarn e também não interfere sobre o aumento de Mcarn em resposta à suplementação de BA. Estes resultados sugerem que a atividade muscular ou o estado de treinamento não influenciam a capacidade de síntese de Mcarn em resposta à suplementação de beta-alanina / BACKGROUND: it is currently unclear whether muscle activity and exercise training affect the ability of the skeletal muscle to synthesise carnosine in response to beta-alanine supplementation. PURPOSE: to study the impact of the extremes of muscle activity and inactivity on muscle carnosine content (Mcarn) and Mcarn loading in response to beta-alanine supplementation. METHODS: 16 trained male with spinal cord injury (SCI) (ASIA scale: AIS A or AIS B) were divided into 2 groups: beta-alanine (BA) (N = 11) and placebo (PL) (N = 5). Muscle biopsies samples were obtained from active deltoid and paralysed vastus lateralis at baseline and after 28 days of β-alanine supplementation (6.4 g.day-1). Unpaired t-tests were applied to compare Mcarn at baseline and the absolute pre-post change in vastus lateralis and deltoid. Mixed model was used to compare Mcarn values within- and between-subjects. RESULTS: (mean±SD): Baseline Mcarn concentration in vastus lateralis was significantly higher than in deltoid (32.0±12 vs. 20.5±6.1 mmol.kg-1 dry muscle; p=0.02). Absolute changes in Mcarn was significantly higher in the BA group in comparison with PL for both vastus lateralis (BA: 17.6±10.4 mmol.kg-1 dry muscle; PL: 2.5±2.3 mmol.kg-1 dry muscle; p=0.002) and deltoid (BA: 15.7±6.8 mmol?kg-1 dry muscle; PL: 1.4±2.7 mmol?kg-1 dry muscle; p<0.001). Absolut changes in Mcarn following BA supplementation between inactive vastus lateralis and active deltoid was not different (vastus lateralis: 17.6±10.4; deltoid: 15.7±6.8 mmol?kg-1 dry muscle; p=0.6). CONCLUSION: chronic muscle inactivity due to paralysis in SCI does not affect Mcarn at baseline and does not affect Mcarn loading in response to BA supplementation. These results suggest that muscle activity or training status does not influence Mcarn synthesis capacity in response to beta-alanine supplementation
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Efeitos do pré-condicionamento isquêmico em subsequentes desempenhos de 50 metros na natação / Effects of remote ischemic preconditioning in subsequent 50 meters performance in swimmingLisbôa, Felipe Domingos 27 June 2016 (has links)
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Previous issue date: 2016-06-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present study aimed to determine the effects of Ischemic preconditioning (IPC) on 50 meters swim performance, in the technical variables and in blood lactate. Ten federated swimmers (20 ± 3 years, 1.82 ± 0.05 m, 77 ± 5 kg and 24.79 ± 1.04 seconds in the 50 meters freestyle) participated in a repeated measures design. The protocol consisted of three visits, anthropometric assessment were performed in the first visit, the second and third (random order) to three subsequent 50 meters performances in an Olympic pool. The first was performed at one hour (D1), the second at two hours (D2) and third at eight hours (D8) after application of IPC or control condition (CTRL). In addition to performance measurement, was measured the blood lactate accumulation (Δ [Lac]), furthermore, the technical parameters relating to the stroke length (SL), stroke frequency (SR) and stroke index (SI) were measured over three passages during the race. IPC had a 0.85% mean effect in performance improvement. Although the effect was not significant in D1 (0.37 %, p = 0.25), there was a clear effect of treatment in D2 and D8 (1.02 % and 1.18 %; p < 0.01, respectively). Moreover, the improvement in performance was accompanied by an increasing in Δ[Lac] in D2 (IPC: 9.04 vs CTRL: 7.77 mmol/L; p < 0.01) and in D8 (IPC: 9.55 vs CTRL: 8.52 mmol/L; p = 0.05), as well as the analysis of technical index during each passage identified a greater SR in D2 and D8. Based on our results, we suggest that a minimum of two hours should be given for there a positive effect of IPC on performance, and this effect remains at least eight hours. In addition, it is likely that increased glycolytic contribution, reflected by higher Δ[Lac], may have led a greater SR and a consequent improvement in performance in D2 and D8 after IPC application. / O presente estudo teve como objetivo verificar os efeitos do pré-condicionamento isquêmico (PCI) sobre o desempenho de 50 metros, nas variáveis técnicas e no lactato sanguíneo. Dez nadadores federados (20 ± 3 anos, 1,82 ± 0,05 m, 77 ± 5 kg e 24,79 ± 1,04 segundos nos 50 metros livres) participaram de um delineamento de medidas repetidas. O protocolo foi composto por três visitas, sendo a primeira uma avaliação antropométrica, a segunda e a terceira (em ordem randômica) a três subsequentes desempenhos de 50 metros em piscina olímpica, sendo o primeiro à uma hora (D1), o segundo a duas (D2) horas e o terceiro a oito horas (D8) após aplicação do PCI ou condição controle (CTRL). Além da medida de desempenho, foi mensurada a diferença (Δ[Lac]) do lactato pico pós exercício do pré exercício de cada desempenho. Além disso, os índices técnicos referentes ao comprimento de braçada (CB), frequência de braçada (FB) e índice de braçada (IB) foram mensurados durante três trechos na fase de nado. PCI apresentou um efeito médio de 0,85 % de melhora no desempenho. Embora o efeito não tenha sido significativo em D1 (0,37 %; p = 0,25), em D2 e D8 houve um claro efeito do tratamento (1,02 % e 1,18 %; p < 0,01, respectivamente). Ainda, os dados de melhora no desempenho foram acompanhados por um maior Δ[Lac] em D2 (PCI: 9,04 vs CTRL: 7,77 mmol/L; p < 0,01) e em D8 (PCI: 9,55 vs CTRL: 8,52 mmol/L; p = 0,05), como também, a análise por trechos dos índices técnicos permitiu identificar um maior comportamento da FB em D2 e em D8. Com base nestes resultados, pode-se sugerir que um intervalo mínimo de duas horas seja dado para que haja um efeito do PCI no desempenho, sendo que esse efeito perdura por pelo menos 8 horas. Além disso, é provável que uma maior contribuição glicolítica, refletida pelo maior Δ[Lac], possa ter levado a uma maior FB e consequente melhora no desempenho em D2 e D8 após aplicação do PCI.
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Efeito do pré-condicionamento isquêmico em sprints repetidos / The effect of ischemic preconditioning in repeated sprintsSalvador, Amadeo Félix 06 August 2015 (has links)
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Previous issue date: 2015-08-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Intermittent sports require maximum effort interspersed with short periods of recovery that are usually called repeated sprints (SR). In order to improve the SR on competition day, various methods are used, however a method that research is growing is the ischemic preconditioning (IPC). The PCI is the intermittent application of a pressure value in the proximal portion of a preset limb. The aim of the study was to evaluate the effect of PCI on SR performance and related physiological variables. Seven female players (26 ± 3 years, 65.9 ± 8 kg and 161 ± 4 cm) and six male players (21 ± 3 years 77.8 ± 6 kg and 179 ± 7 cm) of sevens rugby conducted randomly four test SR being two preceded by PCI and two by control condition (CTRL). The SR were analyzed in pairs being the end of each pair collected the rating of perceived exertion (PSE). Treatment with PCI showed substantial improvement in the average time of SR (CTRL: 3.31 × / ÷ 2.1 and PCI: 3.25 × / ÷ 2.2 s, p = 0.001) and in the best sprint (CTRL: 3.20 × / ÷ 3.1 and PCI: 3.12 × / ÷ 3.3 s, p = 0.009) for men. However these same variables were not significantly different in women (average time: CTRL: 3.76 × / ÷ 1.4 and PCI: 3.73 × / ÷ 1.5 s, p = 0.15) and (best sprint: CTRL: 3.62 × / ÷ 2.1 to PCI: 3.66 × / ÷ 2.1 s, p = 0.24). When controlled for the initial PSE, PSE also demonstrated significant difference for men (CTRL: 15 ± 0.7 and PCI: 13.9 ± 0.7, p = 0.04) and did not show for women (CTRL: 14.4 and PCI ± 0.7: 13.8 ± 0.7, p = 0.25). Therefore, the PCI is a beneficial strategy for improving performance in SR test in men, but further studies are needed to better understand the PCI treatment relationship in men and women. / Esportes intermitentes requerem esforços máximos intercalados com curtos períodos de recuperação que são geralmente denominados sprints repetidos (SR). Com intuito de melhorar o SR no dia da competição, vários métodos são utilizados, entretanto um método em crescente investigação é o précondicionamento isquêmico (PCI). O PCI consiste na aplicação intermitente de um valor de pressão na porção proximal de um membro pré-definido. O objetivo do estudo foi avaliar o efeito do PCI no desempenho do SR e variáveis fisiológicas relacionadas. Sete jogadoras (26 ± 3 anos, 65,9 ± 8 kg e 161 ± 4 cm) e seis jogadores (21 ± 3 anos 77,8 ± 6 kg e 179 ± 7 cm) de rugby sevens realizaram de forma randomizada quatro testes de SR sendo dois precedidos de PCI e dois em condição controle (CTRL). Os SR foram analisados em pares sendo ao fim de cada par coletada a percepção subjetiva de esforço (PSE). O tratamento com PCI apresentou melhora substancial no tempo médio do SR (CTRL: 3,31 ×/÷ 2,1 s e PCI: 3.25 ×/÷ 2.2 s, p=0.001) e no melhor sprint (CTRL: 3,20 ×/÷ 3.1 s e PCI: 3,12 ×/÷ 3,3 s, p=0.009) para os homens. Entretanto estas mesmas variáveis não apresentaram diferenças significativas nas mulheres (tempo médio: CTRL: 3,76 ×/÷ 1,4 s e PCI: 3,73 ×/÷ 1,5 s, p=0,15) e (melhor sprint: CTRL: 3,62 ×/÷ 2,1 s e PCI: 3,66 ×/÷ 2,1 s, p=0,24). Quando controlado pela PSE inicial, a PSE também demostrou diferença significativa para os homens (CTRL: 15 ± 0,7 e PCI: 13.9 ± 0,7, p=0,04) e não demostrou para as mulheres (CTRL: 14,4 ± 0,7 e PCI: 13,8 ± 0,7, p=0,25). Portanto, o PCI é uma estratégia benéfica para melhora do desempenho em teste de SR em homens, porém futuros estudos são necessários para entender melhor a relação do tratamento de PCI em homens e mulheres.
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