Chronic Chikungunya arthralgia reduces functionality, quality of life and occupational performance: descriptive cross-sectional study / Artralgia crônica por Chikungunya reduz funcionalidade, qualidade de vida e performance ocupacional: estudo descritivo transversal

ABSTRACT BACKGROUND AND OBJECTIVES: Chikungunya virus (CHIKV) chronic polyarthralgia deteriorates general functionality and work productivity. The objective of this study was to evaluate functionality, pain, quality of life, and sleep quality of individuals with chronic CHIKV arthralgia and correlate them with clinical symptoms, work productivity, and activity impairment. METHODS: This is a descriptive cross-sectional study with 61 chronic CHIKV arthralgia patients. Functionality was assessed using the Health Assessment Questionnaire (HAQ). Pain intensity and interference were measured by using the Visual Analog Scale (VAS) and the Brief Pain Inventory Short Form (BPI), respectively. Quality of life and sleep were evaluated using the Short Form 36 Health Survey (SF-36) and the Pittsburgh Sleep Quality Index (PSQI), respectively. Work Productivity and Activity Impairment (WPAI) questionnaire was used to assess the effects of health in general symptoms on work. RESULTS: Low and moderate level of function was present in 39.4% and 55.7% of the sample, respectively. Moderate pain (5.57 ± 2.25), poor sleep quality (47.54%), and sleep disturbances (42.63%) were also observed. Pearson correlations showed significant correlation between absenteeism and presenteeism with HAQ scores (p = 0.03; r = 0.39 and p = 0.01; r = 0.43, respectively), BPI interference (p = 0.02; r = 0.41 and p = 0.001; r = 0.58, respectively) and SF-36 physical score (p = 0.007; r = -0.49 and p = 0.01; r = 0.58, respectively). Activity impairment showed a significant correlation with HAQ (p = 0.01; r = 0.44), BPI interference (p = 0.006; r = 0.5), SF-36 physical score (p = 0.01; r = -0.6) and SF-36 total score (p = 0.01; r = -0.44). Overall work productivity loss only correlated with BPI interference (p = 0.04; r = 0.37). CONCLUSION: These results suggest that CHIKV chronic arthralgia showed bilateral moderate pain in large joints that impacts activities of daily life, work productivity, and functional activity. HIGHLIGHTS Chronic chikungunya reduces functionality and causes moderate pain and poor sleep quality Clinical symptoms impact daily living activity, work productivity, and activity impairment. Functionality, pain, and sleep correlate with occupational performance.

RESUMO JUSTIFICATIVA E OBJETIVOS: A poliartralgia crônica do vírus Chikungunya (CHIKV) deteriora a funcionalidade e a produtividade do trabalho. O objetivo deste estudo foi avaliar funcionalidade, dor, qualidade de vida e sono de indivíduos com artralgia crônica por CHIKV correlacionada com sintomas clínicos, produtividade do trabalho e comprometimento das atividades. MÉTODOS: Trata-se de um estudo transversal descritivo com 61 pacientes crônicos de artralgia da CHIKV. A intensidade e a interferência da dor foram medidas usando a Escala Analógica Visual (EAV) e o Brief Pain Inventory Short Form (BPI), respectivamente. A qualidade de vida e o sono foram avaliados usando o Short Form 36 Health Survey (SF-36) e o Pittsburgh Sleep Quality Index (PSQI), respectivamente. O questionário Work Productivity and Activity Impairment (WPAI) foi usado para avaliar os efeitos dos sintomas gerais da saúde no trabalho. RESULTADOS: Foi observado um nível de funcionalidade baixo em 39,4% e moderado em 55,7% da amostra. Nível de dor moderada (5,57 ± 2,25), má qualidade do sono (47,54%) e distúrbios do sono (42,63%) também foram observados. O teste de Pearson apresentou correlação significativa entre absenteísmo e presenteísmo com as pontuações de Health Assessment Questionnaire (HAQ) (p = 0,03; r = 0,39 e p = 0,01; r = 0,43 respectivamente), interferência do BPI (p = 0,02; r = 0,41 e p = 0,001; r = 0,58 respectivamente) e score físico do SF-36 (p = 0,007; r = -0,49 e p = 0,01; r = 0,58, respectivamente). O comprometimento da atividade mostrou uma correlação significativa com o HAQ (p = 0,01; r = 0,44), interferência do BPI (p = 0,006; r = 0,5), pontuação física do SF-36 (p = 0,01; r = -0,6) e pontuação total do SF-36 (p = 0,01; r = -0,44). A perda geral de produtividade no trabalho correlacionou-se apenas com a interferência do BPI (p = 0,04; r = 0,37). CONCLUSÃO: Esses resultados sugerem que a artralgia crônica da CHIKV apresenta dor moderada bilateral em grandes articulações com impacto nas atividades de vida diária, produtividade no trabalho e atividade funcional. DESTAQUES A Chikungunya crônica reduz a funcionalidade e causa dor moderada e má qualidade do sono. Os sintomas clínicos afetam atividades de vida diária, a produtividade no trabalho e comprometimento de atividades. Funcionalidade, dor e sono estão correlacionados com o desempenho profissional.

Does anodal transcranial direct current stimulation over left motor cortex show body side pain-related difference in fibromyalgia? / A estimulação transcraniana por corrente contínua anódica sobre o córtex motor esquerdo apresenta diferença na dor entre os hemicorpos na fibromialgia?

ABSTRACT BACKGROUND AND OBJECTIVES: Fibromyalgia (FM) is a chronic widespread musculoskeletal pain resulting in central sensitization of nociceptive signaling. Transcranial direct current stimulation (tDCS) over the left motor cortex (M1) is a non-invasive neuromodulation technique indicated for a broad range of chronic pain disorders, including FM. Studies suggest that left and right M1 (contralateral and ipsilateral hemisphere of tDCS stimulation) are modulated. But it is necessary to clarify the differences in clinical pain perception comparing the right and left side of the body. This study aimed to evaluate the pain-related difference between right-left side of the body after five sessions of anodal tDCS in women with FM. METHODS: A double-blinded, parallel, randomized, sham-controlled trial with 30 women with FM was performed. Five sessions of anodal C3 and cathodal supraorbital (Fp2) tDCS were conducted (2 mA for 20 min). Pain, impact of FM and anxiety were evaluated. No statistically significant three-way interaction between time, stimulation type and body side were found. RESULTS: Active-tDCS showed significant improvement in pain, but impact of FM and anxiety did not show significant improvement. CONCLUSION: Five sessions of anodal tDCS over the left M1 improves pain in women with FM, however there was no difference between right-left body sides.

RESUMO JUSTIFICATIVA E OBJETIVOS: A fibromialgia (FM) é uma dor musculoesquelética crônica generalizada que resulta na sensibilização central da sinalização nociceptiva. A estimulação transcraniana de corrente contínua (eTCC) sobre o córtex motor esquerdo (M1) é uma técnica de neuromodulação não invasiva indicada para uma ampla gama de distúrbios de dor crônica, incluindo a FM. Estudos sugerem a modulação do M1 esquerdo e direito (hemisfério contralateral e ipsilateral da eTCC). Mas é necessário esclarecer as diferenças na percepção clínica da dor comparando os lados direito e esquerdo do corpo. Este estudo teve como objetivo avaliar a diferença relacionada à dor entre o lado direito e esquerdo do corpo após cinco sessões de eTCC anodal em mulheres com FM. MÉTODOS: Foi realizado um estudo duplo-cego, paralelo, randomizado e controlado por sham com 30 mulheres com FM. Foram realizadas cinco sessões de eTCC anodais C3 e supraorbitais catodais (Fp2) (2 mA por 20 min). Foram avaliados a dor, o impacto da FM e a ansiedade. Não foi encontrada nenhuma interação de três vias estatisticamente significativa entre tempo, tipo de estimulação e lado do corpo. RESULTADOS: A eTCC-Ativa mostrou uma melhora significativa na dor, mas o impacto da FM e da ansiedade não mostrou uma melhora significativa. CONCLUSÃO: Cinco sessões de eTCC anodal sobre o M1 esquerdo melhoram a dor nas mulheres com FM, entretanto não houve diferença entre os lados direito e esquerdo do corpo.

Acute effect of high-definition and conventional tDCS on exercise performance and psychophysiological responses in endurance athletes: a randomized controlled trial.

Transcranial direct current stimulation (tDCS) has been used aiming to boost exercise performance and inconsistent findings have been reported. One possible explanation is related to the limitations of the so-called "conventional" tDCS, which uses large rectangular electrodes, resulting in a diffuse electric field. A new tDCS technique called high-definition tDCS (HD-tDCS) has been recently developed. HD-tDCS uses small ring electrodes and produces improved focality and greater magnitude of its aftereffects. This study tested whether HD-tDCS would improve exercise performance to a greater extent than conventional tDCS. Twelve endurance athletes (29.4 ± 7.3 years; 60.15 ± 5.09 ml kg-1 min-1) were enrolled in this single-center, randomized, crossover, and sham-controlled trial. To test reliability, participants performed two time to exhaustion (TTE) tests (control conditions) on a cycle simulator with 80% of peak power until volitional exhaustion. Next, they randomly received HD-tDCS (2.4 mA), conventional (2.0 mA), or active sham tDCS (2.0 mA) over the motor cortex for 20-min before performing the TTE test. TTE, heart rate (HR), associative thoughts, peripheral (lower limbs), and whole-body ratings of perceived exertion (RPE) were recorded every minute. Outcome measures were reliable. There was no difference in TTE between HD-tDCS (853.1 ± 288.6 s), simulated conventional (827.8 ± 278.7 s), sham (794.3 ± 271.2 s), or control conditions (TTE1 = 751.1 ± 261.6 s or TTE2 = 770.8 ± 250.6 s) [F(1.95; 21.4) = 1.537; P = 0.24; η2p = 0.123]. There was no effect on peripheral or whole-body RPE and associative thoughts (P > 0.05). No serious adverse effect was reported. A single session of neither HD-tDCS nor conventional tDCS changed exercise performance and psychophysiological responses in athletes, suggesting that a ceiling effect may exist.

Latin American and Caribbean consensus on noninvasive central nervous system neuromodulation for chronic pain management (LAC2-NIN-CP).

INTRODUCTION: Chronic pain (CP) is highly prevalent and generally undertreated health condition. Noninvasive brain stimulation may contribute to decrease pain intensity and influence other aspects related to CP. OBJECTIVE: To provide consensus-based recommendations for the use of noninvasive brain stimulation in clinical practice. METHODS: Systematic review of the literature searching for randomized clinical trials followed by consensus panel. Recommendations also involved a cost-estimation study. RESULTS: The systematic review wielded 24 transcranial direct current stimulation (tDCS) and 22 repetitive transcranial magnetic stimulation (rTMS) studies. The following recommendations were provided: (1) Level A for anodal tDCS over the primary motor cortex (M1) in fibromyalgia, and level B for peripheral neuropathic pain, abdominal pain, and migraine; bifrontal (F3/F4) tDCS and M1 high-definition (HD)-tDCS for fibromyalgia; Oz/Cz tDCS for migraine and for secondary benefits such as improvement in quality of life, decrease in anxiety, and increase in pressure pain threshold; (2) level A recommendation for high-frequency (HF) rTMS over M1 for fibromyalgia and neuropathic pain, and level B for myofascial or musculoskeletal pain, complex regional pain syndrome, and migraine; (3) level A recommendation against the use of anodal M1 tDCS for low back pain; and (4) level B recommendation against the use of HF rTMS over the left dorsolateral prefrontal cortex in the control of pain. CONCLUSION: Transcranial DCS and rTMS are recommended techniques to be used in the control of CP conditions, with low to moderate analgesic effects, and no severe adverse events. These recommendations are based on a systematic review of the literature and a consensus made by experts in the field. Readers should use it as part of the resources available to decision-making.

Psychological responses, muscle damage, inflammation, and delayed onset muscle soreness to high-intensity interval and moderate-intensity continuous exercise in overweight men.

We compared in-task affect to HIIE and MICE, and its relationship with time spent at different metabolic domains, perceived exertion (RPE), self-efficacy, enjoyment, and future intention of exercise in overweight inactive men. Muscle damage and soreness, and inflammation were assessed post-exercise. Fifteen participants (28.9 ±â€¯5.0 yr; 29.2 ±â€¯3.8 kg/m2) completed a HIIE (10 × 1 min at 100% Vmax, 1 min recovery) and MICE (20 min at 55-59% VO2reserve) session. Affect, alertness, RPE, and self-efficacy were assessed in-task, and enjoyment and future intention post-task. At baseline, 24 and 48 h, creatine kinase, lactate dehydrogenase, interleukin-6 and -10, tumor necrosis factor alpha, and muscle soreness were assessed. Affect (-3.1 ±â€¯1.8 vs. 0.8 ±â€¯1.8, P < .001) and self-efficacy (70 ±â€¯15 vs. 90 ±â€¯15%, P < .001) were lower, while RPE and alertness were higher in HIIE compared to MICE (Ps ≤ .02). Affect was negatively correlated with RPE in HIIE (r = -0.90) and MICE (r = -0.72), and time spent above respiratory compensation point in HIIE (r = -0.59). Affect was positively correlated with self-efficacy in MICE (r = 0.74). Enjoyment, future intention, muscle damage and soreness, and inflammation were similar between HIIE and MICE post-exercise. Therefore, in-task HIIE was experienced as unpleasant compared to MICE, but the psychological and physiological responses post-task were similar in overweight inactive men.

Effect of walk training combined with blood flow restriction on resting heart rate variability and resting blood pressure in middle-aged men

Aim: To investigate the effects of low-intensity walk training with and without blood flow restriction (BRF) on resting heart rate variability (HRV) and blood pressure (BP) in middle-aged men. Methods: Twenty-one men were randomly assigned into the walk training group with (BRF-W; n = 11) and without (NOR-W; n = 10) BFR. The resting HRV and blood pressure were assessed pre- and post-6 weeks of the intervention [3 times/week, 5 sets of 3-min walking (6 km.h-1) with 1-min of rest, totalizing 18 sessions of training]. The BFR-W group received the occlusive stimulus before of training sessions though of a standard sphygmomanometer and performed the training sessions with the vascular occlusion (80-100 mmHg) in both the legs. Results: Only BRF-W group improved HRV on time domain indices (SDNN and RMSSD; p < 0.05) after training but it was not found differences on frequency domain indices. In addition, systolic blood pressure (SBP) improved after training (PRE: 128.5 ± 5.9 vs POST: 119.1 ± 8.6 mmHg; Cohen's d = -1.30; p < 0.01) only in BFR-W group. There was not a significant difference on diastolic blood pressure (DBP) after training, however, effect size was moderate for BFR-W (Cohen's d = -0.56; p > 0.05). Conclusion: Our results showed that walking training with blood flow restriction can improve health cardiovascular parameters in middle-aged men.(AU)

Efeitos agudos do exercício físico no tratamento da dependência química / Acute effects of physical exercise in addiction treatment / Efectos agudos del ejercicio físico en el tratamiento de la adicción

Resumo Foram avaliados os efeitos do exercício físico na capacidade de atenção, na memória, no desejo de usar drogas, na percepção de esforço e prazer e no estado de humor de 16 indivíduos em tratamento para dependência de drogas. Foram usados a escala de Brunel, o teste de cancelamento de números, o teste dos blocos de Corsi, a escala de Borg e escala de valência afetiva ao esforço físico nas situações controle, pré e pós-realização de uma sessão de exercícios físicos (60 min). Foi observada redução no desejo de usar drogas e no tempo de execução do teste de cancelamento de números, e aumento no número de blocos recordados. Os resultados apontam a importância do profissional da educação física nas equipes para tratamento da dependência química.

Abstract We evaluated the effects of exercise on alertness and memory, the desire to use drugs, the perception of effort and pleasure and mood state, of 16 individuals in treatment for drug addiction. We used tests and scales to assess mood, attention, memory, perceived effort and affect related to exercise, in the situations: Control, Pre and Post completion of an exercise session (60 min). We observed a significant reduction in the desire to use drugs and in the execution time of the test cancellation numbers, and an increase of the number of blocks recalled. The results support the importance of the Professional of Physical Education for treatment of chemical dependency.

Resumen Se evaluaron los efectos del ejercicio físico en el estado de alerta, memoria, el deseo de consumir drogas, la percepción del esfuerzo y placer, y en el estado de ánimo de 16 personas en tratamiento por adicción a las drogas. Se utilizaron pruebas y escalas para evaluar el estado de ánimo, la atención, la memoria visuoespacial, el esfuerzo y el afecto percibido en relación con el ejercicio físico en situaciones de: control, previamente y posteriormente a la finalización de una sesión de ejercicio (60 min). Se observó una reducción del deseo de consumir drogas y del tiempo de ejecución del test de cancelación de números y un aumento del número de bloques recordados. Los resultados indican la importancia de los profesionales de la educación física en el tratamiento de la dependencia química.

EFEITO DO ESFORÇO FÍSICO NO DESEMPENHO DE TIRO DE POLICIAIS MILITARES DO BATALHÃO DE CHOQUE / EFFECT OF PHYSICAL EFFORT ON SHOOTING PERFORMANCE OF MILITARY OFFICERS OF THE RIOT POLICE / EFECTO DEL ESFUERZO FÍSICO EN LA EJECUCIÓN DEL TIRO DE LOS POLICÍAS MILITARES DEL BATALLÓN ANTIDISTURBIOS

RESUMO Introdução: O uso de arma de fogo por policiais militares normalmente é precedido por perseguição a pé, e as alterações fisiológicas produzidas pelo esforço físico podem afetar o desempenho do tiro. Objetivo: Verificar o efeito do esforço físico sobre o desempenho de tiro em policiais militares. Métodos: A amostra foi constituída por 15 homens (34,1 ± 5,4 anos; 81,4 ± 8,8 kg; 171,3 ± 5,6 cm; 27,7 ± 2,3 kg/m²; 44,9 ± 4,0 ml.kg-1.min-1) do batalhão de choque da polícia militar. Na primeira sessão, os participantes realizaram um teste de esforço máximo em esteira no qual se mediu o consumo pico de oxigênio (VO2pico). Na segunda sessão, foi avaliado o desempenho (pontuação) e tempo de tiro pré e pós-esforço físico e o tempo gasto no circuito de corrida com obstáculos (297 m). O índice de eficiência de tiro foi calculado pela razão entre a pontuação total e tempo de execução de tiro. O teste de Shapiro-Wilk confirmou a normalidade da distribuição dos dados. Utilizou-se o teste t pareado para comparação das variáveis desfecho pré e pós-esforço e o coeficiente de correlação de Pearson. Resultados: O tempo para completar o percurso de corrida foi 75,3 ± 4,4 s. O desempenho (20,4 ± 11,4 vs. 17,6 ± 9,3 pontos), tempo (4,48 ± 1,1 vs. 4,23 ± 0,9 s) e eficiência de tiro (4,69 ± 2,7 vs. 4,35 ± 2,7 pts./s) não apresentaram diferenças significativas (P > 0,2). Além disso, detectou-se uma correlação entre o VO2pico e o tempo de execução da corrida (r = -0,64; P = 0,01), mas não com o desempenho de tiro (P > 0,05). Conclusão: O esforço físico não afeta o desempenho de tiro de policiais militares. Apesar de o nível de aptidão aeróbica não ser associado ao desempenho de tiro, foi associado ao desempenho físico realizado previamente aos disparos.

ABSTRACT Introduction: The use of firearms by military police officers is usually preceded by pursuit on foot, and the physiological changes produced by physical exertion may affect shooting performance. Objective: To verify the effect of physical effort on shooting performance in military police officers. Methods: The sample consisted of 15 men (34.1 ± 5.4 years; 81.4 ± 8.8 kg; 171.3 ± 5.6 cm; 27.7 ± 2.3 kg/m²; 44.9 ± 4.0 ml.kg-1.min-1) of the riot police. In the first session, the subjects performed a maximal treadmill stress test in which the peak oxygen consumption (VO2peak) was measured. In the second session, shooting performance (score) and shooting time were measured pre and post-exercise, as well as the time spent to complete a circuit of obstacle running (297 m). Shooting efficiency index was calculated as the ratio between total score and shooting time. The Shapiro-Wilk test confirmed the normal distribution of the data. A paired t-test was used to compare the post-exertion outcomes variables as well as the Pearson correlation coefficient. Results: The time to complete the running circuit was 75.3 ± 4.4 s. Shooting performance (20.4 ± 11.4 vs. 17.6 ± 9.3 points), time (4.48 ± 1.1 vs. 4.23 ± 0.9 s), and efficiency (4.69 ± 2.7 vs. 4.35 ± 2.7 pts/s) did not present significant differences (P>0.2). Additionally, a correlation was detected between VO2peak and running time (r = -0.64; P=0.01), but not with shooting performance (P>0.05). Conclusion: Physical exertion does not affect shooting performance of military police officers. Although the level of aerobic fitness was not associated with shooting performance, it was associated with physical performance prior to shooting.

RESUMEN Introducción: El uso de armas de fuego por los agentes de la policía militar suele ir precedido de persecución a pie, y los cambios fisiológicos inducidos por el esfuerzo físico pueden afectar el rendimiento de disparo. Objetivo: Determinar el efecto del esfuerzo físico en la ejecución del tiro de la policía militar. Métodos: La muestra consistió en 15 hombres (34,1 ± 5,4 años; 81,4 ± 8,8 kg; 171,3 ± 5,6 cm; 27,7 ± 2 3 kg/m²; 44,9 ± 4,0 ml.kg-1.min-1), del batallón antidisturbios de la policía militar. En la primera sesión, los participantes realizaron una prueba de esfuerzo máximo en una cinta rodante en la que se evaluó el pico de consumo de oxígeno (VO2pico). En la segunda sesión se evaluaron el rendimiento (puntuación) y el tiempo de disparo antes y después del esfuerzo físico y el tiempo trascurrido en el circuito de carrera con obstáculos (297 m). El índice de eficiencia de disparo se calculó como la relación entre la puntuación total y el tiempo de ejecución del tiro. La prueba de Shapiro-Wilk confirmó la distribución normal de los datos. Se utilizó la prueba t pareada para la comparación de las variables pre y post-esfuerzo y el coeficiente de correlación de Pearson. Resultados: El tiempo para completar el curso de la carrera fue de 75,3 ± 4,4 s. El rendimiento (20,4 ± 11,4 vs. 17,6 ± 9,3 puntos), el tiempo (4,48 ± 1,1 vs. 4,23 ± 0,9 s) y la eficiencia de disparo (4,69 ± 2,7 vs. 4,35 ± 2,7 pts./s) no mostraron diferencias significativas (P > 0,2). Por otra parte, hemos detectado una correlación entre VO2pico y el tiempo para completar el circuito de la carrera (r = -0,64; p = 0,01), pero no con el rendimiento de disparo (P > 0,05). Conclusión: El esfuerzo físico no afecta el rendimiento de tiro en los policías militares. Aunque el nivel de la capacidad aeróbica no esté asociado con el rendimiento de tiro, se asoció con el rendimiento físico antes de disparar.

Improving cerebral oxygenation, cognition and autonomic nervous system control of a chronic alcohol abuser through a three-month running program.

The abusive use of alcohol has shown to be associated to cerebral damage, impaired cognition, poor autonomic nervous control, impaired cardiovascular health, increased levels of stress and anxiety, depression symptoms and poor quality of life. Aerobic exercise has shown to be an efficient tool to reduce and overcome these issues. In this case report, a patient (forty-four years old, male) under treatment in public psychiatric hospital, classified as having a substance use disorder, underwent a three-month running program. The maximal oxygen consumption increased from 24.2 ml/kg/min to 30.1 ml/kg/min, running time increased from 6 min to 45 min (650%) and distance covered from 765 m to 8700 m (1037.2%). In prefrontal cortex oxygenation, oxyhemoglobin levels improved by 76.1%, deoxyhemoglobin decreased 96.9% and total hemoglobin increased 78.8% during exercise. Reaction time in the cognitive test during rest decreased 23%, and the number of correct answers increased by 266.6%. Parasympathetic cardiac parameters increased in several heart rate variability indices. Thus, we conclude that running exercise performed by an alcoholic patient hospitalized in a psychiatric hospital improves cerebral function, cognition and cardiovascular health.

Reliability of the 6-minute walk test and cardiac autonomic markers in active and sedentary older women / Reprodutibilidade do teste de caminhada de 6 minutos e marcadores autonômicos cardíacos em idosas ativas e sedentárias

Abstract The aim of this study was to examine the reliability of the 6-minute walk test (6MWT) and post-exercise cardiac autonomic markers in physically active and sedentary older women. Eighteen physically active older women (64.2±3.1 years; 63.0±2.7 kg; 1.52±0.06 m; 26.9±2.7 kg.m-2) who performed Tai Chi Chuan for at least 6 months, and 18 sedentary older women (64.0±3.7 years; 63.8±8.9 kg; 1.49±0.05 m; 28.4±3.5 kg.m-2) were submitted to 6MWT in two separate occasions. Immediately after 6MWT, heart rate recovery at one (HRR1’) and two minutes (HRR2’), as well as the heart rate variability (HRV) were recorded. Reliability was verified by intraclass correlation coefficient (ICC) with 95% confidence interval, Bland-Altman plots were used as a measure of agreement, and coefficient of variation (CV) was calculated. High reliability (ICC=0.86) was found for performance in 6MWT (528.8 ± 71.4 m and 473.2 ± 62.4 m; CV=7.9 and VC=8.5%) in both groups. Likewise, high reliability (ICC≥0.84 and ICC≥0.80) was found for HRR 1’ (29.0±11.0 bpm and 17.0±8.0 bpm; VC=30.1% and VC =40.2%) and HRR 2’ (36.0±10.0 bpm and 24.0±9.0 bpm; VC =23.7% and VC =22.8%) in both groups. Regarding HRV, moderate reliability was found in the active group (CCI≥0.57; VC =35-47%), while moderate-high reliability was found in the sedentary group (CCI=0.65-0.76; VC=34-69%). Agreement was found for all variables analyzed. In conclusion, post-exercise 6MWT, HRR, and HRV are reliable tools to assess functional capacity and cardiac autonomic control in physically active and sedentary older women.

Resumo Objetivou-se verificar a reprodutibilidade do teste de caminhada de 6 minutos (TC6) e de marcadores autonômicos cardíacos pós-esforço em idosas fisicamente ativas e sedentárias. Dezoito idosas ativas (64,2 ± 3,1 anos; 63,0 ± 2,7 kg; 1,52 ± 0,06 m; 26,9 ± 2,7 kg.m-2) praticantes de Tai Chi Chuan (≥6 meses de prática) e 18 idosas sedentárias (64,0 ± 3,7 anos; 63,8 ± 8,9 kg; 1,49 ± 0,05 m; 28,4 ± 3,5 kg.m-2) foram submetidas a dois TC6 com uma semana de intervalo. Foram medidas a frequência cardíaca de recuperação (FCR) de um e dois minutos (FCR1’ e FCR2’, respectivamente) e variabilidade da frequência cardíaca (VFC) pós-esforço. A reprodutibilidade foi verificada pelos: coeficiente de correlação intraclasse (CCI) com 95% de intervalo de confiança; análise de concordância de Bland-Altman; e coeficiente de variação (CV). O desempenho no TC6 (528,8±71,4 m e 473,2±62,4 m; CV=7,9% e CV=8,5%) apresentou alta reprodutibilidade (CCI=0,86) em idosas ativas e sedentárias, respectivamente. Similarmente, as medidas pós-esforço da FCR1’ (29,0±11,0 bpm e 17,0±8,0 bpm; CV=30,1% e CV=40,2%) e FCR2’ (36,0±10,0 bpm e 24,0±9,0 bpm; CV=23,7% e CV=22,8%) apresentaram alta reprodutibilidade (CCI≥0,84 e CCI≥0,80) em ambos os grupos. Quanto a VFC verificou-se reprodutibilidade moderada (CCI≥0,57; CV=35-47%) em idosas ativas e moderada-alta nas sedentárias (CCI=0,65-0,76; CV=34-69%). Todas as variáveis apresentaram concordância em ambos os grupos. Conclui-se que o TC6, FCR e VFC pós-esforço são instrumentos reprodutíveis na avaliação da capacidade funcional e controle autonômico cardíaco em idosas ativas e sedentárias.

Estimulação cerebral na promoção da saúde e melhoria do desempenho físico / Brain stimulation for health and exercise performance improvement

O avanço tecnológico das últimas décadas tem proporcionado o uso eficaz de técnicas não-invasivas na neuromodulação cerebral. Atualmente, as principais técnicas de neuromodulação são a estimulação magnética transcraniana (EMT) e a estimulação transcraniana por corrente contínua (ETCC). Por meio de revisão da literatura, o presente estudo aborda: a) história da estimulação cerebral; b) mecanismos de ação estudados através da neurofisiologia motora, farmacologia, neuroimagem e animais experimentais; c) perspectivas de aplicações da estimulação cerebral para promoção da saúde e melhoria do desempenho físico, incluindo o controle autonômico cardíaco e hipotensão pós-exercício, o controle de apetite e a modulação da fadiga e desempenho físico; e d) aspectos de segurança referentes ao uso da ETCC. Dessa forma, a ETCC parece ser uma técnica efetiva e segura para modular a função cerebral e podemos vislumbrar algumas perspectivas de aplicação no âmbito da ingestão alimentar, saúde cardiovascular e desempenho físico...

The technological advances of the last decades have provided the effective use of noninvasive techniques in neuromodulation with concomitant health benefits. Currently, the main neuromodulation techniques are transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). Through literature review, this study addresses the a) history of brain stimulation and the b) mechanisms of action studied by motor neurophysiology, pharmacology, neuroimaging, and experimental animals. Moreover, it is presented the c) perspectives for applications of brain stimulation for promoting health and improving physical performance, including cardiac autonomic control and post-exercise hypotension, control and modulation of appetite, fatigue and physical performance. Finally, we describe d) the security aspects related to the use of tDCS. Thus, tDCS seems to be an effective and safe technique to modulate brain function and suggests some application associated to food intake, cardiovascular health and physical performance...

Percepção subjetiva do esforço, resposta afetiva e hipotensão pós-exercício em sessão de Tai Chi Chuan / Rating of perceived exertion, affective response and post-exercise hypotension in Tai Chi Chuan session

O objetivo do estudo foi analisar a percepção subjetiva do esforço (PSE), resposta afetiva (RA) e pressão arterial pós-exercício em sessão aguda de Tai Chi Chuan (TCC). Vinte e quatro mulheres (47-79 anos; 9 normotensas e 15 hipertensas) foram submetidas a uma sessão de TCC e uma sessão controle (delineamento cruzado). A PSE foi avaliada pela escala de Borg (CR10), a RA pela escala de valência afetiva (+5/-5) e a pressão arterial (PA) pelo método oscilométrico (5, 10, 25, 20, 25 e 30 min pós-sessão). Redução significante da PA sistólica foi identificada aos 20 e 25 min após a sessão de TCC somente nas hipertensas. Os valores de RA e PSE foram +2,8 ± 1,9 e 3,5 ± 1,2, respectivamente. Os resultados sugerem que uma sessão de TCC de intensidade moderada foi prazerosa para as voluntárias (hipertensas e normotensas), embora tenha induzido discreto efeito hipotensor agudo na PA sistólica somente das hipertensas.

The aim of the study was to analyze the rating of perceived exertion (RPE), affective response (AR), and blood pressure (BP) post-exercise in acute Tai Chi Chuan (TCC) session. Twenty-four women (47-79 years; 9 normotensive and 15 hypertensive) performed one TCC and one control session (cross-over design). The RPE was assessed using the Borg's scale (CR10), the AR was assessed by the Feeling Scale (+5/-5) and the BP by the oscillometric method (5, 10, 15, 20, 25, and 30min post-TCC session). A significant systolic BP reduction was observed in the 20 and 25min post-TCC session only in the hypertensive women. The AR and RPE values were +2.8 ± 1.9 e 3.5 ± 1.2, respectively. The results suggest that a moderate TCC exercise bout was pleasurable for the volunteers (normotensive and hypertensive), although it has induced a slight acute hypotensive effect on the systolic BP only in the hypertensive women.

Efeito da prática do Tai Chi Chuan sobre a resistência aeróbia de idosas sedentárias / Effect of Tai Chi Chuan practice on aerobic resistance of sedentary elderly women

OBJETIVO: Investigar o efeito da prática do Tai Chi Chuan (TCC) sobre a resistência aeróbia de idosas sedentárias. Métodos: Fizeram parte do estudo 11 idosas sedentárias (67,9 ± 6,8 anos; 25,9 ± 2,8 kg/m²), as quais foram submetidas aos testes de marcha estacionária de dois minutos e teste de caminhada de seis minutos pré e pós-intervenção de 12 semanas de TCC. RESULTADOS: Houve aumento da resistência aeróbia das idosas analisadas após 12 semanas de prática de TCC, demonstrado tanto por meio do teste de caminhada de seis minutos (510 ± 64 vs. 536 ± 63 metros; p = 0,006) quanto no teste de marcha estacionária de dois minutos (83 ± 20 vs. 110 ± 19 execuções; p = 0,001). CONCLUSÃO: De acordo com os resultados obtidos, é possível concluir que a prática do TCC é capaz de promover aumento da resistência aeróbia de idosas sedentárias.

OBJECTIVE: To investigate the effect of Tai Chi Chuan(TCC) practice on cardiorespiratory fitness of sedentary elderly women. Methods:A total of 11 sedentary elderly women (67.9 ± 6.8 years; 25.9 ± 2.8 kg·m-2)were submitted to six-minute walk test and two-minute step testbefore and after a 12-week TCC training program. RESULTS: Improvements were observed on cardiorespiratory fitness of elderly women analyzed after a 12-week TCC training program, through six-minute walk test (510 ± 64 vs. 536 ± 63 meters; p= 0.006)and two-minute step test(83 ± 20 vs. 110 ± 19 executions; p= 0.001). CONCLUSION: According with obtained results, itis possible to conclude that the TCC practice may promote an increase in cardiorespiratory fitness in sedentary elderly women.

Programa de pós-graduação em educação física da Universidade Federal do Rio Grande do Norte (PPGEF/UFRN) / Postgraduate program in physical education, Federal University of Rio Grande do Norte

O presente artigo apresenta o Programa de Pós-Graduação em Educação Física da Universidade Federal do Rio Grande do Norte (PPGEF/UFRN). Apresentam informações organizadas em tópicos: breve histórico; objetivos e organização acadêmica do PPGEF/UFRN; informações sobre corpo docente e linhas de pesquisa; cooperação e mobilidade; financiamento e apoio institucional. Trata sobre dificuldades encontradas e ações estratégicas para o desenvolvimento e consolidação do Programa.

The present article presents the Postgraduate Program in Physical Education from the Federal University of Rio Grande do Norte (PPGEF/UFRN). Briefly presents the history of the program, its objectives and academic organization, program?s faculty, research areas, cooperation and mobility, financial and institutional support. Discuss dificulties and strategic planning for the develpment and consolidation of the Program.

A estimulação transcraniana por corrente contínua como recurso ergogênico: uma nova perspectiva no meio esportivo / Transcranial direct current stimulation as an ergogenic aid: a new perspective in sport

Nas duas últimas décadas tem-se verificado um considerável aumento no interesse de um grande número de pesquisadores em investigar o potencial de diferentes recursos ergogênicos que possam contribuir na melhoria do desempenho físico de atletas de diferentes modalidades. Grande parte dos estudos tem focado os mecanismos subjacentes ao desenvolvimento da fadiga, pelo fato de que este fenômeno complexo é considerado um fator limitante do desempenho esportivo. Sendo assim, recursos ergogênicos que são eficientes em protelar o desenvolvimento da fadiga podem melhorar o desempenho esportivo. Apesar de haver muitas discussões sobre a fadiga, sua causa exata ainda é um assunto controverso. Apesar disso, tem sido sugerido que mecanismos corticais podem estar envolvidos e que estudos sobre a modulação de regiões cerebrais específicas podem trazer respostas valiosas para entender melhor este fenômeno. Atualmente, a estimulação transcraniana por corrente contínua (ETCC) vem sendo utilizada como uma ferramenta não invasiva capaz de modular a excitabilidade de regiões específicas do córtex cerebral. Dados preliminares têm demonstrado que a ETCC anódica é capaz de aumentar a excitabilidade do córtex motor por até uma hora após sua aplicação, e também aumentar o tempo até em exercício isométrico até à exaustão. Estes dados sugerem ser provável que a ETCC possa ser utilizada como uma ferramenta em pesquisas sobre mecanismos envolvidos no desenvolvimento da fadiga e, talvez, como um possível recurso ergogênico para atletas.

The last two decades has followed an increase in interest from a large number of researchers interested in investigating the ergogenic potential of different resources that might assist in improving the physical performance of athletes in different sports. Most studies have focused on the mechanisms underlying the development of fatigue as this complex phenomenon is a limiting factor in sports performance. Thus, ergogenic resources that are effective in delaying the development of fatigue may improve athletic performance. Despite many discussions about fatigue, its exact cause is still a controversial subject. However, it has been suggested that cortical mechanisms may be involved and studies that have tried to modulate specific brain regions can provide valuable answers to better understand this phenomenon. Currently, (tDCS) has been used as a noninvasive tool that can modulate the excitability of specific regions of the cerebral cortex. Preliminary data have shown that tDCS anode is able to increase the excitability of motor cortex for up to one hour after its application and also increase the time until exhaustion in isometric exercise. These data suggest that tDCS can probably be used as a tool in research on mechanisms involved in the development of fatigue and perhaps as a potential ergogenic aid for athletes..

Can neuromuscular fatigue threshold be determined by short and non-exhaustive bouts? / Pode o limiar de fadiga neuromuscular ser determinado por testes curtos e não exaustivos?

The present study determined the neuromuscular fatigue threshold (NFT) using four different time-periods of analysis of the electromyographic signal and compared these estimations with critical power (CP). Fifteen healthy young men (73.6 ± 5.1 kg, 177.8 ± 7.0 cm, 23.4 ± 5.2 years) performed 3-4 different severe constant workload trials until exhaustion on a cycle ergometer with simultaneous SEMG signals acquisition. The obtained data permitted NFT estimation with four different periods of analysis as follows: initial 30s (T30), 1min (T1), 2min (T2) and total time (TT), as well as CP. T30 and T1 were significantly higher than TT and CP and, T2 and TT did not differ between each other, and both were significantly higher than CP. In addition, TT was significantly correlated to CP (0.72; P < 0.05) and to T2 (0.58; P < 0.05). We conclude that NFT overestimates CP, independent of the time-period analysis used for its determination.

O presente estudo determinou o Limiar de Fadiga Neuromuscular - LFNM usando quatro diferentes períodos de análise do sinal eletromiográfico e comparou essas estimativas com a Potência Crítica - PC. Quinze homens saudáveis do sexo masculino (73,6 ± 5,1 kg, 177,8 ± 7,0 cm, 23,4 ± 5,2 anos) realizaram 3-4 testes severos de carga constante até a exaustão em um cicloergômetro com simultânea aquisição de sinais SEMG. Os dados obtidos permitiram a estimativa de LFNM em quatro períodos diferentes: 30 segundos iniciais (T30), um minuto (T1), dois minutos (T2), tempo total (TT), assim como PC. T30 e T1 foram significativamente maiores do que TT e PC e, T2 e TT não se diferiram entre si e foram maiores que PC. Além disso, TT foi significativamente correlacionado com PC (0,72; P < 0,05) e com T2 (0,58; P < 0,05). Dessa forma, conclui-se que LFNM superestima PC, independente do tempo de análise utilizado para sua determinação.

O nível de treinamento não influencia a percepção subjetiva de esforço durante um teste incremental / Training level does not influence the rating of perceived exertion during an incremental test

Níveis de treinamento distintos, associados à experiência em realizar esforços exaustivos podem produzir diferentes sensações frente à fadiga. O objetivo deste estudo foi comparar a percepção subjetiva de esforço (PSE) entre ciclistas e não-ciclistas durante teste incremental máximo (TIMAX). Participaram do estudo 23 indivíduos que foram divididos em grupo ciclistas (GC) (n = 12; idade 26,5 ± 4,7 anos; massa corporal 68,2 ± 11kg; estatura 176 ± 8,6cm) e grupo não-ciclistas (GNC) (n=11; idade 25,2 ± 4,0 anos; massa corporal 72,9 ± 9kg; estatura 175,1 ± 6,3cm). Todos realizaram um TIMAX, até a exaustão, do tipo rampa em ciclossimulador, com início a 0 W e incrementos de 20 W.min-1. Durante TIMAX a PSE foi aferida e anotada a cada 30 segundos de teste e, ao final, a potência máxima (PMAX) atingida pelos indivíduos. O tempo total de cada teste foi normalizado em porcentagens (de 10% a 100%, intervalos de 10%), e foi anotada a respectiva PSE para cada intervalo. Os valores de PMAX para GC e GNC foram 368 ± 12,7W e 256 ± 11,2W, respectivamente (P < 0,01). Os valores das medianas das PSE para GC e GNC não apresentaram diferença significativa para nenhuma porcentagem de tempo. Conclui-se que as respostas de PSE não sofreram alterações entre GC e GNC durante TIMAX, sugerindo que o nível de treinamento não influencia a PSE.

Different training levels, combined with experience in performing exhaustive exercise, may produce different sensations of fatigue. The objective of this study was to compare the rating of perceived exertion (RPE) between cyclists and non-cyclists during a maximal incremental test (ITMAX). Twenty-three subjects were recruited and divided into a cyclist group (CG) (n = 12; age: 26.5 ± 4.7 years, body weight: 68.2 ± 11kg, height: 176 ± 8.6 cm) and a non-cyclist group (NCG) (n = 11; 25.2 ± 4.0 years, body weight: 72.9 ± 9 kg, height: 175.1 ± 6.3 cm). All subjects performed an ITMAX until exhaustion on a cycling simulator, starting at 0 W and with increments of 20 W.min-1. RPE was measured at 30-second intervals during ITMAX and the maximal power output (PMAX) of each subject was also recorded. The total time of each test was normalized to the percentage of completed trial (10% to 100%, intervals of 10%), and the corresponding RPE was recorded. PMAX was 368 ± 12.7 W and 256 ± 11.2 W for CG and NCG, respectively (P < 0.01). No significant difference in median RPE was observed between groups at any time point. In conclusion, RPE responses did not differ between CG and NCG during ITMAX, suggesting that training level does not influence RPE.

Efeitos da suplementação prolongada de creatina mono-hidratada sobre o desempenho anaeróbio de adultos jovens treinados / Effects of long-term creatine monohydrate supplementation on anaerobic performance of trained young adults

O objetivo do presente estudo foi investigar o impacto de oito semanas de suplementação de creatina mono-hidratada (Crm) sobre o desempenho anaeróbio de adultos jovens treinados. Vinte e seis estudantes de educação física, do sexo masculino, saudáveis, foram divididos aleatoriamente em grupo creatina (GCr, n = 13; 22,5 ± 2,7 anos; 74,9 ± 6,8kg, 178,5 ± 4,8cm) e grupo placebo (GPl, n = 13; 22,9 ± 3,2 anos, 71,9 ± 11,3kg, 178,6 ± 4,0cm). Os indivíduos ingeriram em sistema duplo-cego doses de Crm ou placebo-maltodextrina (20 g.d-1 por 5 dias e 3 g.d-1 por 51 dias subsequentes). Ambos os grupos tiveram seus hábitos alimentares e os níveis de aptidão física controlados anteriormente. O teste anaeróbio de Wingate (TW) foi usado para avaliar o desempenho anaeróbio antes e após o período de ingestão de Crm ou placebo. Os índices de desempenho analisados foram: potência pico relativa (PPR), potência média relativa (PMR), trabalho total relativo (TTR) e índice de fadiga (IF). Para tratamento estatístico foi utilizado ANOVA, seguido pelo teste de post hoc Tukey, quando P<0,05. Não foram observadas diferenças significantes nos índices PPR, PMR, TTR e IF após o período de suplementação de Crm (P<0,05). Os resultados do presente estudo sugerem que a suplementação de Crm não parece ser um recurso ergogênico eficiente em esforços físicos de alta intensidade e curta duração que envolve uma única série.

The objective of the present study was to investigate the impact of eight weeks of creatine monohydrate (Crm) supplementation on the anaerobic performance of young trained adults. Twenty-six healthy male physical education students were randomly divided in creatine group (CrG, n = 13; 22.5 ± 2.7 years; 74.9 ± 6.8 kg; 178.5 ± 4.8 cm) and placebo group (PlG, n = 13; 22.9 ± 3.2 years; 71.9 ± 11.3 kg; 178.6 ± 4.0 cm). The subjects received in a double-blind system a Crm or placebo-maltodextrin dose (20 g.d-1 for 5 days and 3 g.d-1 for 51 subsequent days). Both groups had their eating habits and levels of physical fitness previously controlled. The Wingate anaerobic test (WT) was used to evaluate the anaerobic performance before and after the ingestion period of Crm or placebo. The performance indexes assessed were: relative peak power (RPP), relative mean power (RMP), relative total work (RTW) and index of fatigue (IF). ANOVA followed by Tukey post hoc test were used when P<0.05 for statistical treatment. No significant difference in RPP, RMP, RTW or IF was observed after the period of supplementation of Crm (P>0.05). The results of the present study suggest that Crm supplementation does not seem to be an efficient ergogenic resource in high-intensity and short-duration efforts involving a single set.

Efeito da ingestão de cafeína sobre os parâmetros da potência crítica / Effect of caffeine intake on critical power model parameters determined on a cycle ergometer

The aim of this study was to evaluate the effect of caffeine intake on critical power model parameters determined on a cycle ergometer. Eight male subjects participated in this study. A double-blind protocol consisting of the intake of pure caffeine (6 mg/kg) or placebo (maltodextrin) 60 min before testing was used. Subjects were submitted to four constant-load tests on a cycle ergometer. These tests were conducted randomly in the caffeine and placebo groups [checar] at intensities of 80, 90, 100 and 110% maximum power at a rate of 70 rpm until exhaustion to determine the critical power. As a criterion for stopping the test was adopted any rate fall without recovery by more than five seconds. The critical power and anaerobic work capacity were obtained by nonlinear regression and fitting of the curve to a hyperbolic power-time model. The Shapiro-Wilk test and paired Student t-test were used for statistical analysis. No significant differences in critical power were observed between the caffeine and placebo groups (192.9 ± 31.3 vs 197.7 ± 29.4 W, respectively). The anaerobic work capacity was significantly higher in the caffeine group (20.1 ± 5.2 vs 16.3 ± 4.2 W, p<0.01). A high association (r2) was observed between the caffeine and placebo conditions (0.98 ± 0.02 and 0.99 ± 0.0, respectively). We conclude that caffeine intake did not improve critical power performance but increased anaerobic work capacity by influencing performance at loads of higher intensity and shorter duration.

The aim of this study was to evaluate the effect of caffeine intake on critical power model parameters determined on a cycle ergometer. Eight male subjects participated in this study. A double-blind protocol consisting of the intake of pure caffeine (6 mg/kg) or placebo (maltodextrin) 60 min before testing was used. Subjects were submitted to four constant-load tests on a cycle ergometer. These tests were conducted randomly in the caffeine and placebo groups [checar] at intensities of 80, 90, 100 and 110% maximum power at a rate of 70 rpm until exhaustion to determine the critical power. As a criterion for stopping the test was adopted any rate fall without recovery by more than five seconds. The critical power and anaerobic work capacity were obtained by nonlinear regression and fitting of the curve to a hyperbolic power-time model. The Shapiro-Wilk test and paired Student t-test were used for statistical analysis. No significant differences in critical power were observed between the caffeine and placebo groups (192.9 ± 31.3 vs 197.7 ± 29.4 W, respectively). The anaerobic work capacity was significantly higher in the caffeine group (20.1 ± 5.2 vs 16.3 ± 4.2 W, p<0.01). A high association (r2) was observed between the caffeine and placebo conditions (0.98 ± 0.02 and 0.99 ± 0.0, respectively). We conclude that caffeine intake did not improve critical power performance but increased anaerobic work capacity by influencing performance at loads of higher intensity and shorter duration.

Efeito da ingestão de cafeína sobre o limiar de esforço percebido (LEP) / Effect of ingestion of caffeine on perceived exertion threshold (PET)

A cafeína é substância ergogênica utilizada para aprimorar o rendimento esportivo. Com efeitos centrais e periféricos, pode interferir na percepção de fadiga durante esforços exaustivos. O presente estudo objetivou investigar o efeito da ingestão de cafeína sobre o limiar de esforço percebido (LEP). Após estabelecer a carga máxima de trabalho (Wmax) por teste incremental em ciclo ergômetro, oito homens realizaram quatro testes de carga constante (80, 90, 100 e 110% da Wmax) sob ingestão de cafeína (CAF) ou placebo (PLA) para determinação do LEP. Para contrastar os dados, utilizou-se o teste t de Student pareado. Não foram encontradas diferenças significativas entre os valores de LEP em nenhuma das condições, porém, na condição CAF os testes constantes de 100 e 110% apresentaram maior tempo de exaustão (P menor que 0,01), e os testes de 80 e 100% apresentaram menor taxa de aumento da percepção subjetiva de esforço (PSE) (P menor que 0,01). De acordo com os resultados, é possível concluir que o LEP não foi modificado com a suplementação de CAF, mesmo com desempenho superior durante os testes mais intensos e atenuação da taxa de aumento da PSE nas cargas 80 e 100%.

Caffeine is an ergogenic substance used to enhance sports performance. With central and peripheral effects, it may influences the perception of fatigue during exhaustive efforts with central and peripheral effects. The present study aimed to investigate the effects of caffeine ingestion on the perceived exertion threshold (PET). After completing maximum work load (Wmax) test on cycling ergometer, eight men executed four constant load tests (80, 90, 100 and 110% of Wmax) under caffeine (CAF) or placebo (PLA) ingestion for PET determination. The t Student paired test was used to compare PET under the analyzed conditions. There were no significant differences between CAF and PLA conditions for PET. However, during 100 and 110% constant load tests, CAF conditions presented longer exhausting time (P smaller that 0,01) and the tests between 80% and 100% presented lower increasing ratings of perceived exertion (RPE) (P smaller that 0,01). According to the results, it is possible to conclude that PET was not modified with CAF supplementation, even with higher performance during the most intensive tests and attenuation of the increasing rate of RPE in 80% and 100% loads.