Carbohydrate mouth rinse failed to reduce central fatigue, lower perceived exertion, and improve performance during incremental exercise.

We examined if carbohydrate (CHO) mouth rinse may reduce central fatigue and perceived exertion, thus improving maximal incremental test (MIT) performance. Nine recreational cyclists warmed up for 6 min before rinsing a carbohydrate (CHO) or placebo (PLA) solution in their mouth for 10 s in a double-blind, counterbalanced manner. Thereafter, they performed the MIT (25 W·min-1 increases until exhaustion) while cardiopulmonary and ratings of perceived exertion (RPE) responses were obtained. Pre- to post-MIT alterations in voluntary activation (VA) and peak twitch torque (Tw) were determined. Time-to-exhaustion (p = 0.24), peak power output (PPO; p = 0.45), and V̇O2MAX (p = 0.60) were comparable between conditions. Neither treatment main effect nor time-treatment interaction effect were observed in the first and second ventilatory threshold when expressed as absolute or relative V̇O2 (p = 0.78 and p = 0.96, respectively) and power output (p = 0.28 and p = 0.45, respectively) values, although with moderate-to-large effect sizes. RPE increased similarly throughout the tests and was comparable at the ventilatory thresholds (p = 0.56). Despite the time main effect revealing an MIT-induced central and peripheral fatigue as indicated by the reduced VA and Tw, CHO mouth rinse was ineffective in attenuating both fatigues. Hence, rinsing the mouth with CHO was ineffective in reducing central fatigue, lowering RPE, and improving MIT performance expressed as PPO and time-to-exhaustion. However, moderate-to-large effect sizes in power output values at VT1 and VT2 may suggest some beneficial CHO mouth rinse effects on these MIT outcomes.

Carbohydrate mouth rinse improves performance of mentally fatigued cyclists despite null effects on psychological responses.

Mental fatigue reduces exercise performance through an impaired psychological response such as increased perceived exertion. Carbohydrate (CHO) mouth rinses improve exercise performance and perceived exertion likely due to an improved activation in cerebral reward areas, then we investigated if the CHO mouth rinse-improved exercise performance in mentally fatigued individuals was associated with ameliorated reward-related psychological responses. We hypothesised that CHO mouth rinse would be beneficial for mentally fatigued cyclists mainly in high-metabolic disturbance intensities. After familiarization and baseline sessions, well trained cyclists (n = 20) performed a maximal incremental test (MIT) after mental fatigue induction. They completed the MIT either without mouth rinse (MF) or rinsing their mouth with CHO (MF+CHO) or placebo (FM+PLA) solutions at every 25 % of the MIT. Psychological responses such as ratings of perceived exertion (RPE), affective valence, emotional arousal, and motivation were assessed throughout the MIT, while performance was assessed as peak power output and time of exercise. Mental fatigue reduced MIT performance (P < 0.05), but CHO mouth rinse was effective to counteract this deleterious mental fatigue effect (P < 0.05). However, we found null effects of CHO mouth rinses in psychological responses above the VT2 (P > 0.05) such as RPE, affective valence, emotional arousal, and motivation. Correlational analysis showed a significant, but moderate negative correlation between motivation and time of exercise above the VT2 when participants used CHO mouth rinse. In conclusion, the ergogenic CHO mouth rinse effects on MIT performance of mentally fatigued cyclists were irrespective of ameliorated psychological responses to exercise.

No Evidence of Postactivation Performance Enhancement on Endurance Exercises: A Comprehensive Systematic Review and Meta-analysis.

PURPOSE: Narrative reviews have suggested that postactivation induced by warm-up routines is effective to increase endurance exercise performance in real-world scenarios. However, systematic reviews with meta-analysis rather than narrative ones are required to provide an up-to-date summary of the evidence and provide directions for practical decisions. Therefore, we systematically reviewed peer-reviewed and gray literature to determine the certainty of evidence and the relative effects of postactivation performance enhancement (PAPE) in endurance exercises. METHODS: The effects of PAPE on endurance performance were meta-analyzed as a standardized mean difference (SMD) from control conditions within a random-effects model considering polled data and subgroups (PAPE strategies, endurance test modalities, and V̇O 2max -based endurance level). RESULTS: Eligible studies ( n = 35) showed a high risk of bias due to methodological flaws in randomization and blinding procedures. A meta-analysis including 57 comparisons (432 participants) revealed a significant but very small PAPE effect on endurance performance ( Z = 2.49, SMD = 0.15-very small, 95% confidence interval = 0.03 to 0.28) due to exceptional effect sizes reported by two studies (SMD of 2.85 and 2.14). We also observed that neither PAPE strategies nor endurance test modalities or V̇O 2max -based endurance levels influenced the PAPE effects on endurance performance. Meta-regression showed that PAPE effects were correlated neither with the time interval between conditioning routines and endurance exercise nor with endurance exercise duration. We found a very low certainty of evidence that PAPE potentiates endurance performance. CONCLUSIONS: Based on the analyses of bias and certainty of evidence, we found no support to recommend PAPE strategies to improve endurance exercise performance. Significant but very small PAPE effects on endurance performance were due to two exceptional effect sizes.

Ice Massage on the Calf Improves 4-km Running Time Trial Performance in a Normothermic Environment.

Purpose: Local cooling with ice massage is a practical and inexpensive technique to decrease perceptual stress and improve motor performance in hot environments. However, it is unknown whether local cooling with ice massage reduces perceptual responses to exercise and improves performance in a normothermic environment. Thus, we investigated whether ice massage on the calf muscles before a 4 km running time trial (TT4km) reduced the ratings of perceived exertion (RPE) and perceived muscle pain, thereby improving exercise performance in a normothermic environment. Methods: After familiarizations, fourteen recreationally endurance-trained men (age = 21.3 ± 1.2 years; body weight = 67.5 ± 9.2 kg; height = 173.0 ± 5.0 cm) underwent two TT4km on a 400 m track in normothermic conditions with or without ice massage before the trial. The time of running, RPE, and pain perception were recorded every 400 m throughout the TT4km. Results: The local cooling with ice massage increased the mean speed (~ 5.2%, p = 0.03) and decreased the time to complete the TT4km (~ 5.5%, p = 0.03). Accordingly, ice massage also reduced the exercise-derived pain perception (p = 0.028), although no effect has been found in the RPE during the TT4km (p = 0.32). Conclusion: Together, these results showed that local cooling with ice massage before the exercise reduced the exercise-derived pain perception, enabling runners to increase the speed for a comparable RPE during exercise, thereby improving the TT4km performance in a normothermic environment.

A Narrative Review of Current Concerns and Future Perspectives of the Carbohydrate Mouth Rinse Effects on Exercise Performance.

Previous systematic reviews have confirmed that carbohydrate (CHO) mouth rinse may boost physical exercise performance, despite some methodological aspects likely affecting its ergogenic effect. In this review, we discussed if the exercise mode, pre-exercise fasting status, CHO solutions concentration, CHO solutions temperature, mouth rinse duration, and CHO placebo effects may potentially reduce the CHO mouth rinse ergogenic effect, suggesting possible solutions to manage these potential confounders. The effectiveness of CHO mouth rinse as a performance booster is apparently related to the origin of the exercise-induced neuromuscular fatigue, as CHO mouth rinse unequivocally potentiates endurance rather than sprint and strength exercises performance. Furthermore, ergogenic effects have been greater in fasting than fed state, somehow explaining the varied magnitude of the CHO mouth rinse effects in exercise performance. In this regard, the CHO solution concentration and temperature, as well as the mouth rinse duration, may have increased the variability observed in CHO mouth rinse effects in fasting and fed state. Finally, placebo effects have challenged the potential of the CHO mouth rinse as an ergogenic aid. Therefore, we suggest that future studies should consider methodological controls such as sample size and sample homogeneity, proper familiarization with experimental procedures, and the use of alternative placebo designs to provide unbiased evidence regarding the potential of the CHO mouth rinse as an ergogenic aid.

Proof-of-Concept and Test-Retest Reliability Study of Psychological and Physiological Variables of the Mental Fatigue Paradigm.

This study provided a proof-of-concept and test-retest reliability of measures frequently used to assess a mental fatigue paradigm. After familiarization, 28 healthy men performed (40-min) the Rapid Visual Information Processing (RVP) test in a test-retest design, having mental fatigue sensation, motivation, emotional arousal, total mood disturbance, and electroencephalography (EEG) in the prefrontal cortex measured before and after the test. EEG was recorded during a 3-min rest so that the power spectral density of theta (3-7 Hz) and alpha (8-13 Hz) bands was calculated. Pre-to-post RVP test changes in psychological and physiological domains were compared (paired-T tests), and absolute (standard error of measurement (SEM) and minimal difference (MD)) and relative reliability (intraclass correlation coefficient (ICC)) were calculated. The RVP test induced an increase (p < 0.05) in mental fatigue sensation (120.9% (109.4; 132.4)) and total mood disturbance (3.5% (-6.3; 13.3)), and a decrease in motivation (-7.1% (-9.2; -5.1)) and emotional arousal (-16.2% (-19.1; -13.2)). Likewise, EEG theta (59.1% (33.2; 85.0); p < 0.05), but not alpha band, increased due to RVP test. All psychophysiological responses showed poor-to-moderate relative reliability. Changes in mental fatigue sensation and motivation were higher than SEM and MD, but changes in EEG theta band were higher only than SEM. Mental fatigue sensation, motivation, and EEG theta band were sensitive to distinguish a mental fatigue paradigm despite true mental fatigue effects on theta activity may be trivial.

Effects of experimentally induced muscle pain on endurance performance: A proof-of-concept study assessing neurophysiological and perceptual responses.

Pain arising from exercise potentiates fatigue and impairs the performance of endurance exercise. We assessed neurophysiological and perceptual responses to endurance exercise performed under experimentally induced muscle pain by a model that separates muscle pain from muscle fatigue. After a series of pilot studies investigating different hypertonic saline volumes, 17 healthy males performed a preliminary VO2PEAK test before performing a familiarization of the cycling time-to-exhaustion exercise (80% of the peak power output in the VO2PEAK test). Participants, performed a baseline exercise session before the sessions with hypertonic and isotonic saline injections in the vastus lateralis of both legs, in a crossover and counterbalanced design. Neurophysiological and perceptual responses such as electroencephalography (EEG) in frontal, prefrontal, parietal, and motor cortex, electromyography (EMG) of the vastus lateralis and biceps femoris muscles, ratings of perceived exertion (RPE), pain sensation, and affective valence were measured at rest and during exercise. The hypertonic injection reduced the resting EEG alpha-beta ratio in the frontal and prefrontal cortex. When compared to exercise performed after the isotonic injection (430.5 ± 152.6 s), hypertonic injection shortened the time-to-exhaustion (357.5 ± 173.0 s), reduced the EMG of the assessed muscles, and increased the muscle co-contraction during exercise. The hypertonic injection also reduced the EEG alpha-beta ratio in the prefrontal and parietal cortex, increased RPE and pain sensation, and reduced affective valence during exercise. This proof-of-concept study showed that hypertonic injection-induced muscle pain reduced endurance performance, promoting centrally mediated alterations in motor command and cortical activation, as well as an interplay of perceptual responses.

Carbohydrate Mouth Rinse Mitigates Mental Fatigue Effects on Maximal Incremental Test Performance, but Not in Cortical Alterations.

Detrimental mental fatigue effects on exercise performance have been documented in constant workload and time trial exercises, but effects on a maximal incremental test (MIT) remain poorly investigated. Mental fatigue-reduced exercise performance is related to an increased effort sensation, likely due to a reduced prefrontal cortex (PFC) activation and inhibited spontaneous behavior. Interestingly, only a few studies verified if centrally active compounds may mitigate such effects. For example, carbohydrate (CHO) mouth rinse potentiates exercise performance and reduces effort sensation, likely through its effects on PFC activation. However, it is unknown if this centrally mediated effect of CHO mouth rinse may mitigate mental fatigue-reduced exercise performance. After a proof-of-principle study, showing a mental fatigue-reduced MIT performance, we observed that CHO mouth rinse mitigated MIT performance reductions in mentally fatigued cyclists, regardless of PFC alterations. When compared to placebo, mentally fatigued cyclists improved MIT performance by 2.24-2.33% when rinsing their mouth with CHO during MIT. However, PFC and motor cortex activation during MIT in both CHO and placebo mouth rinses were greater than in mental fatigue. Results showed that CHO mouth rinse mitigated the mental fatigue-reduced MIT performance, but challenged the role of CHO mouth rinse on PFC and motor cortex activation.

Caffeine Increased Muscle Endurance Performance Despite Reduced Cortical Activation and Unchanged Neuromuscular Efficiency and Corticomuscular Coherence.

The central and peripheral effects of caffeine remain debatable. We verified whether increases in endurance performance after caffeine ingestion occurred together with changes in primary motor cortex (MC) and prefrontal cortex (PFC) activation, neuromuscular efficiency (NME), and electroencephalography-electromyography coherence (EEG-EMG coherence). Twelve participants performed a time-to-task failure isometric contraction at 70% of the maximal voluntary contraction after ingesting 5 mg/kg of caffeine (CAF) or placebo (PLA), in a crossover and counterbalanced design. MC (Cz) and PFC (Fp1) EEG alpha wave and vastus lateralis (VL) muscle EMG were recorded throughout the exercise. EEG-EMG coherence was calculated through the magnitude squared coherence analysis in MC EEG gamma-wave (CI > 0.0058). Moreover, NME was obtained as the force-VL EMG ratio. When compared to PLA, CAF improved the time to task failure (p = 0.003, d = 0.75), but reduced activation in MC and PFC throughout the exercise (p = 0.027, d = 1.01 and p = 0.045, d = 0.95, respectively). Neither NME (p = 0.802, d = 0.34) nor EEG-EMG coherence (p = 0.628, d = 0.21) was different between CAF and PLA. The results suggest that CAF improved muscular performance through a modified central nervous system (CNS) response rather than through alterations in peripheral muscle or central-peripheral coupling.

Exercício com intensidade autosselecionada para idosos: implicações do afeto em aulas comunitárias / Self-selected intensity exercise for the elderly: implications of affect in community classes

A prescrição da intensidade do exercício de forma autosselecionada em função de maior afeto positivo é uma estratégia utilizada para promover aderência da população na prática de exercícios. Entre-tanto, ainda não foram investigadas as implicações que essa estratégia pode gerar na valência afetiva de idosos em ambientes não laboratoriais e em aulas em grupos. O objetivo desse estudo foi analisar se o exercício com intensidade autosselecionada realizado em grupos de idosos pode influenciar na valência afetiva. A amostra foi composta por 176 idosos, sendo 42 homens, com média de idade 70,70 ± 10,10 anos e 134 mulheres, com média de idade 71,00 ± 6,60 anos. Os idosos vinculados a um centro comunitário reportaram a valência afetiva e percepção subjetiva de esforço após uma caminhada de 30 minutos com intensidade autosselecionada. Os participantes foram alocados em três grupos segundo os tercis de percepção subjetiva de esforço: grupo com baixa (GBPE), média (GMPE) e alta (GAPE) percepção de esforço. Foi identificado que todos grupos se diferenciam entre si na valência afetiva [c² (2) = 50,860; p < 0,05]. A magnitude das diferenças pelo tamanho de efeito foi moderada na análise global (*ES = 0,331) e entre GBPE e GAPE (ES = 0,329). Conclui-se existe uma implicação negativa na valência afetiva em exercício com autosseleção da intensidade rea-lizados por idosos em grupos comunitários, possivelmente causado por fatores psicossociais capazes de influenciar na variabilidade de respostas perceptivas

The self-selected exercise intensity prescription due to greater positive affect is a strategy used to promote adherence of the population to exercise. However, the implications that this strategy may have on the affective valence of the elderly in non-laboratory environments and in group classes have not still investigated. The purpose of this study was to analyze whether self-selected intensity exercise performed in elderly groups can influence affective valence. The sample consisted of 176 elderly, 42 men, with a mean age of 70.70 ± 10.10 years and 134 women, with a mean age of 71.00 ± 6.60 years. The elderly linked to a community center reported affective valence and rating perceived exertion after a 30-minute walk with self-selected intensity. Participants were allocated to three groups according to the terciles of rating perceived exertion: group with low (GBPE), medium (GMPE) and high (GAPE) perceived exertion. It was identified that all groups differ in affective valence [c² (2) = 50,860; p <0.05]. The magnitude of the differences by effect size was moderate in the overall analysis (*ES = 0.331) and between GBPE and GAPE (ES = 0.329). In conclusion, there is a negative implication in affective valence in self-selected exercise intensity performed by the elderly in community groups, possibly caused by psychosocial factors capable of influencing the variability of perceptual responses

Allometric Scale Corrects Performance Outcomes in Special Judo Fitness Test.

We compared results of Special Judo Fitness Test (SJFT) performance of young athletes of two different age categories after correcting body mass (BM) variations by allometric scales. Thirty young judokas (14.2±3.6 years) belonging to two age categories underwent an SJFT: under 15 (U15) years old (12.1±2.4 years; 46.5±15.6 kg; 152.4±11.2 cm) and under 21 years old (U21) (18.2±0.8 years; 77.1±23.5 kg; 174.2±8.9 cm). Allometric exponents of -0.33 and 0.67 were used to correct the influence of BM variations on SJFT performance results. After correction using the -0.33 exponent, U21 showed a higher number of throws (TNT) than U15 (85.5±9.9 and 68.8±12.0, p<0.05, respectively), although the SJFT index had been similar between these groups (67.3±10.1 and 61.7±8.1, p>0.05, respectively). In contrast, TNT normalized by the 0.67 exponent was higher in U15 than U21 (1.55±0.29 and 1.17 ± 0.25, p<0.05, respectively). Likewise, the SJFT index was higher in U15 than in U21 when using the same exponent (1.55±0.29 and 1.17±0.25, p<0.05, respectively). In conclusion, the -0.33 exponent may be useful to remove the influence of BM variations, thus discriminating SJFT performance results in U15 and U21 judokas. Moreover, the 0.67 exponent may overestimate SJFT indices in low-age judokas.

Fatores determinantes da estratégia de ritmo em esportes de endurance / Determinants factors of pacing strategy on endurance sports / Determinantes de la estrategia de ritmo en los deportes de resistencia

Resumo Provas cíclicas de longa duração exigem que atletas tomem decisões acerca do uso de energia durante a prova. Visto isso, diferentes estratégias de ritmo (pacing strategy) foram diagnosticadas a fim de promover uma economia de energia durante o esforço. Portanto, o objetivo desta revisão é apresentar os principais mecanismos da estratégia de ritmo, baseados nos modelos de tomada de decisão sustentados por informações aferentes ou contextuais/intuitivas, que são usadas para calcular e reduzir um possível risco de fadiga prematura durante uma tarefa de endurance.

Abstract Long cyclic exercises require that athletes make decisions about the use of energy during the trial, as this, different pacing strategies were diagnosed in order to promote an economy of energy during exercise. Therefore the aim of this review was to present the major exercise strategy mechanisms, based on the decision-making models supported by accurate afferent information, or contextual / intuitive, which are used to calculate the risk of the exercise/test, and decide to reduce/maintain/increase the pace of exercise/test.

Resumen Las pruebas cíclicas a largo plazo requieren que los atletas tomen decisiones sobre el uso de la energía durante la carrera. De esta manera, se diagnosticaron diferentes estrategias de ritmos (pacing strategy) con el fin de promover una economía de energía durante el esfuerzo. Por tanto, el objetivo de esta revisión es presentar los principales mecanismos de la estrategia de ritmo, basados en los modelos de toma de decisiones con el apoyo de la información aferente exacta, o contextual/intuitiva, que se utiliza para calcular el posible riesgo de cansancio prematuro durante la prueba de resistencia.

Correction to: Effects of Carbohydrate Mouth Rinse on Cycling Time Trial Performance: A Systematic Review and Meta-Analysis.

Section 3.2, Fig. 2: The wording on the x-axis which previously read.

Caffeine improved cycling trial performance in mentally fatigued cyclists, regardless of alterations in prefrontal cortex activation.

PURPOSE: To verify whether caffeine (CAF) could increase the prefrontal cortex (PFC) activation and improve 20 km cycling time trial (TT20km) performance in mentally fatigued cyclists. METHODS: After preliminary TT20km, twelve recreational cyclists (VO2MAX of 58.9 ±â€¯6.2 mL kg min-1) performed a familiarization with a cognitive test to induce mental fatigue (MF) and psychological scales. Thereafter, they performed: 2) a baseline TT20km; 3) a mentally fatigued TT20km (MF); 4 and 5) a mentally fatigued TT20km after CAF (MF + CAF) or placebo (MF + PLA) ingestion, in a double-blind, counterbalanced design. Performance and psychological responses were obtained throughout the TT20km, while PFC electroencephalography (EEG) theta wave was obtained before and after the mental fatigue test. RESULTS: The mental fatigue-induced increase in EEG theta wave (↑ ~ 4.8%) was reverted with CAF (↓ 8.8%) and PLA ingestion (↓ 4.8%). CAF improved TT20km performance in mentally fatigued cyclists by reducing time (p = .00; ↓ ~ 1.7%) and increasing WMEAN (p = .00; ↑ ~ 3.6%), when compared to MF + PLA. The RPE-power output ratio was lower (p = .01), but affect (p = .018), motivation (p = .033) and emotional arousal (p = .001) were greater throughout the TT20km in MF + CAF than in MF + PLA. CONCLUSIONS: CAF ingestion improved TT20km performance and psychological responses in mentally fatigued cyclists, despite the unaltered PFC activation.

Effects of Carbohydrate Mouth Rinse on Cycling Time Trial Performance: A Systematic Review and Meta-Analysis.

BACKGROUND: Despite the growing number of studies reporting carbohydrate mouth rinse effects on endurance performance, no systematic and meta-analysis review has been conducted to elucidate the level of evidence of carbohydrate mouth rinse effects on cycling trial performance such as time-, work-, and distance-based trials. OBJECTIVES: The objective of this study were to establish the effect of a carbohydrate mouth rinse on cycling performance outcomes such as mean power output and time to complete a trial, together with the risk of bias in the cycling-carbohydrate mouth rinse literature. METHODS: We systematically reviewed randomized placebo-controlled trials that assessed carbohydrate mouth rinse effects on mean power output and time to complete the trial. A random-effects meta-analysis assessed the standardized mean difference between carbohydrate and placebo mouth rinses. RESULTS: Thirteen studies (16 trials) were qualitatively (systematic review) and quantitatively (meta-analysis) analyzed with regard to mean power output (n = 175) and time to complete the trial (n = 151). Overall, the reviewed studies showed a low risk of bias and homogeneous results for mean power output (I2 = 0%) and time to complete the trial (I2 = 0%). When compared with placebo, the carbohydrate mouth rinse improved mean power output (standardized mean difference = 0.25; 95% confidence interval 0.04-0.46; p = 0.02), but not the time to complete the trial (standardized mean difference = - 0.13; 95% confidence interval - 0.36 to 0.10; p = 0.25). CONCLUSION: The present systematic and meta-analytic review supports the notion that a carbohydrate mouth rinse has the potential to increase mean power output in cycling trials, despite showing no superiority over placebo in improving time to complete the trials.

Physical education class can improve acute inhibitory control in elementary school students

Abstract Aim: The aim of the study was to analyze the impact of a based-team sports physical education class on inhibitory control of elementary school children. Methods: Were selected 29 elementary school students (13 boys and 16 girls; 10.7 ± 0.7 years old; 43.2 ± 8.2 kg weight; 147 ± 5 cm height). Participants were submitted to a 50-minute sports-based physical education class performed at moderate intensity. Inhibitory control was measured before and immediately after the end of the physical education class by the Stroop Test. Results: Results indicate that the variables derived from Stroop Test performance overall reaction time were significantly reduced after the physical education class (p < 0.05). Conclusion: These results suggest that a 50-minute sports-based physical education class performed at moderate intensity elicited a significant improvement on the inhibitory control elementary school students.

Traditional models of fatigue and physical performance / Modelos tradicionais de fadiga e desempenho físico

ABSTRACT The origin of fatigue has been the focus of studies involved in sports performance, due to the necessity to clarify the mechanistic bases for the reduced capacity to perform considerable effort intensities. According to the traditional conception of fatigue, mechanisms may encompass peripheral and central sites of fatigue. Peripheral fatigue is understood as events related to an inefficient tissue oxygen delivery, metabolic accumulation, muscular acidosis and muscle substrate depletion. In contrast, the central fatigue is mostly related to events in the central nervous system (CNS) that may involve neurotransmitters changes, altered metabolic profile and elevated temperature. Therefore, the current review aimed to discuss the peripheral and central mechanisms of fatigue, thus driving interpretations of the phenomenon.

RESUMO A etiologia da fadiga tem sido objeto de estudo em pesquisas relacionadas ao desempenho esportivo em função da necessidade de esclarecer os mecanismos que reduzem a capacidade de manutenção do desempenho em intensidades elevadas de esforço. A concepção tradicional de fadiga assume que os mecanismos possam ser desencadeados em sítios de ação central ou periférica. A fadiga periférica é compreendida como uma oferta inadequada de oxigênio tecidual, acúmulo de metabólitos e depleção de substrato energético acelerando a acidose muscular. A fadiga central, por sua vez, oriunda do sistema nervoso central (SNC), apresenta alterações nos neurotransmissores, podendo alterar o perfil metabólico e temperatura do SNC. Desta forma, a presente revisão tem como intuito abordar os mecanismos de fadiga central e periférica, norteando futuras interpretações sobre o fenômeno.