Effect of photobiomodulation on maximal lactate production rate on swimmers: a randomized, crossover, double-blind and placebo-controlled study

Abstract Aim: This study aimed to verify the acute effect of photobiomodulation (PBM) on maximal lactate production rate (VLamax) in front crawl swimmers. Methods: Fifteen male swimmers (20.9 ± 2.4-year-old) participated in this study. Three sets of front crawls were performed at distances of 100-, 200- and 400-m under three experimental conditions: PBM (420 J), placebo (PLA) and control (C) in this randomized, crossover, double-blind and placebo-controlled study. PBM or PLA were applied or simulated before performance tests. One-way Anova for repeated measurements were used for statistical analyses. Results: The results showed that the prior PBM application did not affect VLamax in front crawl swimmers: VLamax 100-m (PBM = 0.20 ± 0.05 mmol·L-1·s-1; PLA = 0.20 ± 0.04 mmol·L-1·s-1 and C = 0.21 ± 0.04; mmol·L-1·s-1); 200-m (PBM = 0.09 ± 0.03 mmol·L-1·s-1; PLA = 0.08 ± 0.02 mmol·L-1·s-1 and C = 0.08 ± 0.02 mmol·L-1·s-1) and 400-m (PBM = 0.04 ± 0.01 mmol·L-1·s-1; PLA = 0.04 ± 0.01 mmol·L-1·s-1 and C = 0.03 ± 0.01 mmol·L-1·s-1). Nor effect swim time (ST) performance: ST 100 m (PBM = 65.5 ± 6.3 s; PLA = 65.2 ± 5.6 s; C = 66.0 ± 5.9 s); ST 200 m (PBM = 148.5 ± 17.9 s; PLA = 149.4 ± 16.4 s; C = 150.1 ± 17.9 s); ST 400 m (PBM = 327.7 ± 38.2 s; PLA = 321.6 ± 47.7 s; C = 329.5 ± 41.2 s). Conclusions: PBM application prior front crawl swimming tests did not significantly modify the VLamax on swimmers covering distances of 100-, 200- and 400-m.

Effects of caffeine on central and peripheral fatigue following closed- and open-loop cycling exercises

We examined whether endurance performance and neuromuscular fatigue would be affected by caffeine ingestion during closed- and open-loop exercises. Nine cyclists performed a closed-loop (4,000-m cycling time trial) and an open-loop exercise (work rate fixed at mean power of the closed-loop trial) 60 min after ingesting caffeine (CAF, 5 mg/kg) or placebo (PLA, cellulose). Central and peripheral fatigue was quantified via pre- to post-exercise decrease in quadriceps voluntary activation and potentiated twitch force, respectively. Test sensitivity for detecting caffeine-induced improvements in exercise performance was calculated as the mean change in time divided by the error of measurement. Caffeine ingestion reduced the time of the closed-loop trial (PLA: 375.1±14.5 s vs CAF: 368.2±14.9 s, P=0.024) and increased exercise tolerance during the open-loop trial (PLA: 418.2±99.5 s vs CAF: 552.5±106.5 s, P=0.001), with similar calculated sensitivity indices (1.5, 90%CI: 0.7-2.9 vs 2.8, 90%CI: 1.9-5.1). The reduction in voluntary activation was more pronounced (P=0.019) in open- (-6.8±8.3%) than in closed-loop exercises (-1.9±4.4%), but there was no difference between open- and closed-loop exercises for the potentiated twitch force reduction (-25.6±12.8 vs -26.6±12.0%, P>0.05). Caffeine had no effect on central and peripheral fatigue development in either mode of exercise. In conclusion, caffeine improved endurance performance in both modes of exercise without influence on post-exercise central and peripheral fatigue, with the open-loop exercise imposing a greater challenge to central fatigue tolerance.

Suplementos ergogénicos: la evidencia más allá de una moda / Ergogenic supplements: evidence beyond trends

A pesar de que son muchos los suplementos deportivos que se etiquetan como ergogénicos, pocos son los que realmente demuestran su efectividad. Si bien estos suplementos están destinados principalmente para deportistas de élite, su uso se ha masificado en la po-blación general, esto debido a la falta de regulación en uso y venta, así como por los potenciales beneficios que podrían otorgar. Frente a estas limitantes ¿cuál es la efectividad de estos productos más allá de la moda? En esta comunicación breve se revisa la evidencia respecto al efecto y la efectividad de 11 suplementos y plantas utilizados como ayuda ergogénica. A pesar de los múltiples beneficios en los suplementos ergogénicos identificados, es necesario tener precaución al momento de generalizar los resultados obtenidos por algunos ergogénicos, ya que su efecto podría ser secundario y/o estar condicionado por otros factores. Es necesario mayores estudios clínicos que permitan asociar una relación causa-efecto en el rendimiento deportivo y la población general.

Although many sports supplements have been identified as ergogenic, few have demonstrated their effectiveness. They were originally created for high-performance athletes, but their consumption has incremented in the general population. Lack of regulation to sell and use these products is one of the main problems in our society. In this context, what is the effectiveness of ergogenic supplements beyond the trends? In this short communication, 11 ergogenic supplements and plants will be discussed regarding their effect and efficacy. However, considering that their effect could be a side effect of other factors, findings should be analyzed with caution. Further clinical trials are needed to estimate the causal effect in sports performance and the general population.

Acute effect of sodium bicarbonate supplementation by resistant training practices / Efeito agudo da suplementação de bicarbonato de sódio por práticas de treinamento de resistência

Currently, the use of sodium bicarbonate (SB) as an ergogenic supplement has been linked to improved performance in several high-intensity and short time interval modalities because it is a natural buffer of the body fluids of the human body. This study aimed to evaluate the acute effect of SB supplementation on muscle strength endurance of resistance training practitioners. Crossover clinical trial, placebo-controlled (PL), and single-masked, included 10 trained adult men. The maximum repetition (1RM) and exhaustion tests with 80% 1RM were performed in the extensor chair and direct thread. In all sessions, the volunteers were verbally stimulated, the total maximum repetitions in the exercises and the blood lactate concentration were measured. SB was supplemented at a dose of 0.3 g/kg body mass. Statistical analysis was performed using SPSS version 25.0. The Shapiro­Wilktest was used to evaluate the normality of the data, and the Student's t-test was used for independent and paired samples. The size of the Cohen's effect was calculated, and the significance level was set at p<0.05. Comparing the supplements, no significant differences were found in all variables tested. However, when comparing pretest and posttest periods, significant differences were found between lactate concentrations, with considerably large effect sizes (> 1.00).SB supplementation by endurance training practitioners induces blood alkalosis, which reduces fatigue and possibly improves muscle strength endurance

Atualmente, o uso de bicarbonato de sódio (SB) como suplemento ergogênico tem sido associado a um melhor desempenho em várias modalidades de alta intensidade e intervalos de tempo curtos, pois é um amortecedor natural dos fluidos corporais do corpo humano. Este estudo teve como objetivo avaliar o efeito agudo da suplementação de SB na resistência da força muscular de praticantes de treinamento de resistência. Ensaio clínico cruzado, controlado por placebo (PL) e com máscara única, incluiu 10 homens adultos treinados. Os testes de repetição máxima (1RM) e exaustão com 80% de 1RM foram realizados na cadeira extensora e na rosca direta. Em todas as sessões, os voluntários foram estimulados verbalmente, foram medidas as repetições máximas totais nos exercícios e a concentração de lactato sanguíneo. O SB foi suplementado na dose de 0,3 g / kg de massa corporal. A análise estatística foi realizada no SPSS versão 25.0. O teste Shapiro-Wilk foi usado para avaliar a normalidade dos dados, e o teste t de Student foi usado para amostras independentes e emparelhadas. O tamanho do efeito de Cohen foi calculado e o nível de significância foi estabelecido em p <0,05. Comparando os suplementos, não foram encontradas diferenças significativas em todas as variáveis testadas. No entanto, ao comparar os períodos pré e pós-teste, foram encontradas diferenças significativas entre as concentrações de lactato, com tamanhos de efeito consideravelmente grandes (> 1,00). A suplementação de SB por praticantes de treinamento de resistência induz alcalose no sangue, o que reduz a fadiga e possivelmente melhora a resistência da força muscular.

Effect of a Period of Magnesium Supplementation on Muscle Strength and Resistance of Bodybuilders

Objective:The purpose of this study is to determine the effect of magnesium supplements on the muscular strength of active men.Materials and Methods:Samples were matched into two groups. Magnesium supplements (containing 47 mg of calcium and 250 mg of magnesium oxide produced by al-Hawi Company) were given to the experimental group and the placebo that was completely similar to the supplements for thecontrol group. The tablets are given to every other subject individually and they performed strength training. Supplements were ingested before strength training in the gym and the supplements were consumed with a glass of water. The statistical population of the study included male bodybuilders’ athletes who are regularly excising three days a week in Shahre Kord sports clubs. 40 subjects were selected from people who were interested to participate in the research. After selecting the samples, they are randomly divided into two groups A and B (double-blind method). The strength of the athletes was measured by the CPR machine based on the 1-RM and their resistance by more repetition ofbench press with a standard device using 1-RM by 0.5 Kg in the gym. Results:The results of Wilks' lambda test showed that there is a significant difference between the experimental and control groups in one of the measurements related to arms muscle strength and chest muscle strength, while there is no a significant difference between the two groups in measurements related to muscle strength and resistance of the upper body, which means that magnesium supplementation for 8 weeks has had a significant effect on the strength of the hands and chest muscles of the bodybuilders ‘athlete.Conclusion:Magnesium supplementation can affect the strength of upper body’s muscles of men.

Frontiers and Progress in Neuro-Biomechanical Ergogenic Technology / 医用生物力学

In recent years, the effects of the neuro-biomechanical ergogenic technology on improving and enhancing human function and physical movement performance have widely attracted certain attentions. This review summarized the recent achievements in the effects of non-invasive brain stimulation (NIBS) and biomechanical ergogenic technology based on sports equipment on human physical performance, and further explored the possible mechanisms for improving and promoting human physical performance. The obtained preliminary evidence based on animal experiments and biomechanical researches on neuromotor control under multi-joint movement were also summarized, so as to explain the coordinated development of human function enhancement at cerebral cortex regulation and neuromuscular coordinated control levels, and interpret its integration with sports equipment. This review ultimately provided certain references for the future frontier development and research position of neuro-biomechanics and human sports biomechanics.

Acute melatonin administration enhances aerobic tolerance: an analysis of biochemical and hematological parameters

Aims: This study is aimed at testing the acute melatonin administration (oral; 6 mg) on aerobic tolerance at cycloergometer and analyzing the consequences on biochemical and hematological parameters. Methods: The maximal aerobic capacity intensity (iMAC) at cycloergometer of eleven male healthy men (24.18±3.92 years-old; 87.07±12.48 kg; 1.82±0.05 m; 26.18±3.63 kg/m2; and 16.28±5.77 % of fat) was individually determined and used to perform a time to exhaustion (tlim) trial of 30 minutes after melatonin or placebo administration. We observed 48-72h interval between tests, performed in a double-blind experiment design. In order to determine hematological and biochemical parameters we collected venous blood samples before and after tlim. Statistical significance was set at 5%. Results The intensity and the lactatemia corresponding to the maximal aerobic capacity were 120.88±18.78 W and 3.32±1.03 mmol.L-1, respectively. The tlim with placebo (33.94±15.26 min, confidence interval = 24.92 - 42.95) was significantly lower than the tlim with melatonin (41.94±17.22 min; CI = 31.76 - 52.12; p = 0.03; 19.06%; effect size = 0.49). All of the 21 analyzed blood physiological variables resulted in no significant variation after tlim when placebo was compared to melatonin, except for total sera cholesterol (lower after exercise with melatonin). Conclusion: Acute melatonin administration enhanced aerobic tolerance at iMAC in 19% at cycloergometer; however, the biochemical and hematological variables assessed were not significantly modulated.(AU)

Carbohydrate mouth rinse reduces rating of perceived exertion but does not affect performance and energy systems contribution during a high-intensity exercise

Aim: The study aimed to verify the effect of carbohydrate (CHO) mouth rinse on time to exhaustion, energy systems contribution and rating of perceived exertion (RPE) during a high-intensity exercise. Methods Fourteen men performed an incremental exercise test to determine their maximal oxygen uptake and peak power output (PPO) and two time-to-exhaustion tests at 110% of PPO. Participants rinsed their mouth with 25ml of 6.4% of CHO or placebo (PLA) solution immediately before the time-to-exhaustion test, using a crossover design. The contribution of the energy systems was calculated using the free software GEDAE-LaB®. Results: Time to exhaustion was similar between the conditions (CHO:174.3±42.8s; PLA:166.7±26.3s; p=0.33). In addition, there was no difference between the CHO and PLA condition for aerobic (CHO:135.1±41.2kJ and PLA:129.8±35.3kJ, p=0.34), anaerobic lactic (CHO:57.6±17.1kJ and PLA:53.4±15.1kJ, p=0.10), and anaerobic alactic (CHO:10.4±8.4kJ and PLA:13.2±9.2kJ, p=0.37) contribution. Consequently, total energy expenditure was similar between conditions (CHO:203.2±46.4kJ and PLA:196.5±45.2kJ, p=0.15). However, CHO mouth rinse reduced the RPE at the moment of exhaustion (CHO:18.2±1.0units and PLA:19.1±1.1units; p=0.02). Conclusion: CHO mouth rinse neither increased time to exhaustion nor altered energy systems contribution during a high-intensity exercise, but reduced the perceived effort at the exhaustion.(AU)

Impact of a Multi-Component Dietary Supplement on Blood Testosterone, Nitrate/Nitrite and Physical Performance in Resistance-Trained Men.

Both D-aspartic acid (DAA) and nitrate have received considerable attention in recent years. Vitamin D3 is also considered important for overall physical health and has been associated with elevated blood testosterone. The present study evaluated the impact of a DAA-nitrate-vitamin D3 containing dietary supplement on anaerobic exercise performance, blood testosterone and nitrate/nitrite in men. Methods: 24 resistance-trained men (mean age: 23 years) were assigned to ingest a DAA-nitrate-vitamin D3 supplement or a placebo for 28 days. Exercise performance (upper body muscle power, force, and endurance; Wingate cycle sprints), in addition to blood total and free testosterone and nitrate/nitrite was measured before and after 14 and 28 days of supplementation. Results: No increase in total or free testosterone was noted at either measurement time (p>0.05), with values remaining stable or decreasing slightly following intake of the supplement. Nitrate/nitrite was increased significantly following intake of the supplement (p<0.05), from 19.1±2.1 µmol∙L-1 (pre) to 70.0±12.4 µmol∙L-1 at 14 days and 68.6±7.7 µmol∙L-1 at 28 days. Despite this increase in nitrate/nitrite, no performance variable was impacted in a statistically significant manner by supplementation (p>0.05). However, the cumulative number of repetitions performed during a five-set bench press challenge was 11.3% higher after 28 days of supplementation, as compared to 3.6% higher for placebo. Conclusion: Twenty-eight days of treatment with a DAA-nitrate-vitamin D3 supplement increases blood nitrate/nitrite and can moderately improve repetitive bench press performance. However, this supplement does not result in an increase in total or free testosterone or any other performance measure.

Efeito agudo da suplementação de cafeína sobre o desempenho físico durante teste incremental de esforço / Acute effect of caffeine suplementation on physical performance during an incremental effort test

O presente estudo teve como objetivo investigar os efeitos da ingestão de cafeína (CAF) sobre a velocidade de corrida (VC) referente à intensidade do primeiro limiar ventilatório (LV1) e velocidade máxima de corrida (Vmáx). Para tanto, oito mulheres saudáveis, ativas fisicamente, realizaram dois testes incrementais máximos (TImáx) em esteira ergométrica em duas condições diferentes, sob ingestão de CAF e placebo (PLA). Para contrastar os dados, utilizou-se o teste t de Student pareado. Houve diferença significativa (P ≤0,05) na VC (PLA 7,87 ± 1,72 km/h, CAF 8,50 ± 1,69 km/h), na frequência cardíaca (PLA 152,37 ± 21,41 bpm, CAF 167,00 ± 14,71 bpm) e na VE (PLA 31,40 ± 8,53 L/min, CAF 34,46 ± 9,52 L/min), na intensidade referente ao LV1. Diferentemente, na Vmáx não foram observadas diferenças significativas na VC, FC e vetilação (VE) em ambas as condições. É possível concluir que a VC, FC e VE foram modificadas com a suplementação de CAF na intensidade do LV1, mas não na Vmáx.

The present study aimed to investigate the effects of caffeine (CAF) ingestion on running speed (RS) on the intensity of the first ventilatory threshold (VT1) and maximum running speed (Vmax). Therefore, eight healthy women, physically active performed two maximal incremental tests (TImax) on the treadmill at two different conditions under CAF intake and placebo (PLA). To contrast the data, we used the paired Student t test. There were statistically significant differences (P ≤ 0.05) in RS (PLA 7.87 ± 1.72 km / h, 8.50 ± 1.69 CAF km / h), heart rate (PLA 152.37 ± 21.41 bpm, CAF 167.00 ± 14.71 bpm) and LV (PLA 31.40 ± 8.53 L / min, CAF 34.46 ± 9.52 L / min), the intensity for the VT1. In contrast, the Vmax were not significant differences in VC, HR and ventilation (VE) in both conditions. It is possible to conclude that the VC, VE and HR were modified with the supplementation of CAF in the intensity of VT1, but not in the Vmax.

Carbohydrate mouth rinse does not improve repeated sprint performance / Enxágue bucal com carboidrato não melhora o desempenho em sprints repetidos

The objective of this study was to evaluate the effect of a carbohydrate mouth rinse on the repeated sprint ability (RSA) of young soccer players. Nine youth soccer players (15.0 ± 1.5 years; 60.7 ± 4.84 kg; 1.72 ± 0.05 m; 20.5 ± 1.25 kg/m²) were selected. The athletes were submitted to an RSA test consisting of six sprints of 40 m (going/ return = 20 m + 20 m), separated by 20 s of passive recovery, under three experimental conditions: carbohydrate mouth rinse (CHO) or placebo (PLA) and control (CON). The mouth rinses containing CHO or PLA were administered 5 min and immediately before the beginning of the test in doses of 100 mL. The best sprint time (RSAbest), mean sprint time (RSAmean), and drop-off in sprint performance (fatigue index) were determined for the different treatments. One-way ANOVA for repeated measures did not identify significant differences (P > 0.05) in RSAbest (CHO = 7.30 ± 0.31 s; PLA = 7.30 ± 0.30 s; CON = 7.26 ± 0.16 s), RSAmean (CHO = 7.71 ± 0.30 s; PLA = 7.71 ± 0.25 s; CON = 7.66 ± 0.24 s), or fatigue index (CHO = 5.58 ± 2.16%; PLA = 5.77 ± 3.04%; CON = 5.55 ± 3.72%). The results suggest that a carbohydrate mouth rinse does not improve the repeated sprint performance of young soccer players.

O objetivo deste trabalho foi analisar os efeitos do enxágue bucal com carboidrato sobre o desempenho, durante sprints repetidos (RSA), de jovens jogadores de futebol. Nove atletas de futebol da categoria infantil (15,0 ± 1,5 anos; 60,7 ± 4,84 kg; 1,72 ± 0,05 m; 20,5 ± 1,25 kg/m²) foram submetidos ao teste de RSA. O teste foi composto por seis sprints de 40 m (ida/volta = 20 m + 20 m), separados por 20 s de recuperação passiva com três condições experimentais: enxágue bucal com carboidrato (CHO) ou placebo (PLA) e controle (CON). O enxágue bucal com CHO ou PLA foi conduzido 5 min antes e imediatamente antes do início dos testes em doses de 100 mL. O tempo do melhor sprint (RSAbest), a média de tempo dos sprints (RSAmean) e o índice de fadiga (IF) foram determinados nas diferentes condições experimentais. ANOVA one-way para medidas repetidas não identificou diferenças significantes (P > 0,05) para RSAbest (CHO = 7,30 ± 0,31 s; PLA = 7,30 ± 0,30 s; CON = 7,26 ± 0,16 s), RSAmean (CHO = 7,71 ± 0,30 s; PLA = 7,71 ± 0,25 s; CON = 7,66 ± 0,24 s) e IF (CHO = 5,58 ± 2,16%; PLA = 5,77 ± 3,04%; CON = 5,55 ± 3,72%). Os resultados sugerem que o enxágue bucal com CHO não parece capaz de melhorar o desempenho, sobre sprints repetidos, de jovens jogadores de futebol.

Efecto del grito personal como recurso ergogénico en la fuerza de prensión de mano en adolescentes / Effect of personal shout as ergogenic resource in hand grip strength in adolescents

El objetivo del estudio fue identificar el efecto del grito personal como recurso ergogénico en la mejora de la fuerza de prensión de mano en adolescentes. Se contó con la participación de 44 adolescentes, 25 mujeres y 19 hombres, con una edad promedio de 16.10 +/- 0.7 años. Para calcular la fuerza de prensión de mano, los sujetos aplicaban la mayor prensión de mano en un dinamómetro, tres intentos con la mano dominante y tres con la no dominante aplicando un grito en el momento de la ejecución y tres intentos más con cada mano sin aplicar el grito. Para efecto del análisis estadístico se tomó el mejor intento de cada mano bajo cada condición. Se aplicó un Análisis de Varianza de Tres Vías Mixto para el análisis e interpretación de los datos. Se concluye que la utilización del grito personal en el momento de realizar la acción de prensión de mano, incrementó la cantidad de fuerza medida en kilogramos, independientemente que se realizara con la mano dominante o no dominante; además de que este efecto positivo fue evidenciado en ambos géneros lo que demuestra que los resultados fueron producto de un estímulo neuromuscular, más que de factores de dominancia o de género.

The objective of this research was to identify the effects of the persons shout as an ergogenic source to improve the hand grip of adolescent. The group was formed by 44 adolescents, 25 females and 19 males. The average age was 16.10 +/- 0.7 years. To determine the hand grip strength, the participants had to apply their strength of their hand in a dynamometer, three times with the dominant hand and three times with the non-dominant hand, shouting at the moment of the execution, and three trials with each hand and without shouting. For the analysis, was elected the best try of every hand under each condition. An analysis of variance of Three Mixed Ways was used for the analysis and interpretation of the data. As a conclusion, was found that shouting in the moment of performing an action of dexterity of hand grip, it increases the amount of force applied measured in kilograms, regardless of the hand it is made with; besides the positive effect, it was evidenced that in both genders the results were the product of a stimulus rather than the neuromuscular factors or the dominance of gender.

Efeito da ingestão de cafeína sobre o desempenho físico e estado de humor de ciclistas / Effects of caffeine on performance and mood of cyclists

O objetivo do estudo foi analisar os efeitos da ingestão de cafeína sobre o desempenho físico e estado de humor de ciclistas em teste contrarrelógio de 1 km. Dez ciclistas do sexo masculino realizaram aleatoriamente um teste contrarrelógio de 1 km em duas condições experimentais: ingestão de cafeína (CAF - 6 mg.kg-1) e placebo (PL) 60 min antes do teste. Durante os testes foram obtidas as medidas de tempo total e estado de humor pelo questionário de Brunel (BRUMS). Para comparações dos parâmetros tempo total e estado de humor, foi utilizado o teste t de Student pareado e teste Wilcoxon, respectivamente. Nenhuma diferença estatisticamente significante foi encontrada no tempo total e no estado de humor nas condições CAF e PL (P>0,05). Os resultados sugerem que a cafeína não melhora o desempenho físico e nem altera o estado de humor dos atletas em um teste contrarrelógio de 1 km.

This study analyzed the effects of caffeine ingestion on physical performance and mood state of cyclists in a 1km time trial test. Ten male cyclists performed randomly a 1km time-trial test under two experimental conditions: Caffeine (CAF - 6 mg.kg-1) and placebo (PL) 60 min before the test. During the test were obtained the total time and the mood using the Brunel questionnaire (BRUMS). For comparisons of total time and mood states it was applied the paired Student's t-test and Wilcoxon test, respectively. No significant differences were found in the total time to complete tests and in the mood states between CAF and PL conditions (P>0.05). The results suggested that caffeine does not improve performance or change the mood of cyclists in a 1km time trial test.

Prevalência do uso e efeitos de recursos ergogênicos por praticantes de musculação nas academias brasileiras: uma revisão sistematizada / Prevalence of the use and ergogenic resources effects by body builders in Brazilian academies: a systematic review

O objetivo da presente revisão sistemática foi traçar a prevalência, as formas de indicação e os efeitos adversos dos suplementos alimentares (SA) e esteroides anabólicos androgênicos (EAA), cujo uso é relatado por praticantes de musculação nas academias de ginástica do Brasil. Para desenvolvimento deste estudo foi realizada, em novembro de 2011, uma busca nas bases de dados Medline, Scielo, Bireme e Lilacs utilizando as palavras-chave: esteroides anabólicos androgênicos, suplementos nutricionais e academias de ginástica. Para ser incluído, o estudo deveria ter investigado o uso de recursos ergogênicos em academias do Brasil. De acordo com os critérios de inclusão, foram selecionadas em um primeiro momento 93 investigações, mas apenas 18 foram incluídas. Os estudos selecionados demonstraram que as regiões Sul e Sudeste são as que possuem maior número de estudos. A maior prevalência de consumo dos SA foi em Belo Horizonte (90,8%), seguido por Vitória (70%), Cascavel (66%) e Curitiba (50,61%), e os produtos mais consumidos foram: proteínas, aminoácidos e creatinas. Para os EAA, a maior prevalência encontrada foi em Belo Horizonte com 85%, seguido por Aracaju (31%) e Rio Grande do Sul (24,9%). Os produtos mais utilizados foram o Decanoato de Nandrolona, a Testosterona e o Estanozolol. Os efeitos colaterais predominantes dos EAA foram surgimento de acne (46 a 94%) e agressividade (47 a 73%). Tanto o consumo de SA quanto o uso dos esteroides anabólicos androgênicos encontram-se exacerbados nas academias brasileiras, principalmente, na região Sudeste. Além disso, o uso abusivo dos EAA ocorre devido à falta de informações sobre suas contra indicações, repercutindo em inúmeros efeitos adversos à saúde.

Objective: The objective of the present study was to systematically review the prevalence, indicative ways, and adverse effects of ergogenic resources, such as dietary supplements (DS) and anabolic androgenic steroids (AAS), that were reported, by bodybuilders in gyms in Brazil. Methods: References search was performed in November 2011 in the Medline, SciELO, BIREME, and Lilacs data basis by the key-words: anabolic-androgenic steroids, nutritional supplements, and gyms. To be included the studies should have investigated the prevalence of the use of ergogenic resources in gyms in Brazil. Ninety-three investigations were selected, but only 18 were included. Results: The highest prevalence of DS consumption was in Belo Horizonte (90.8%), followed by Vitoria (70%), Cascavel (66%) and Curitiba (50.61%). For the AAS use, the highest prevalence was in Belo Horizonte with 85%, followed by Aracaju (31%) and Rio Grande do Sul (24.9%). The products mainly consumed as DS were: derived proteins, amino acids and creatine. The most widely used AAS increase were Deca-Durabolin, Sustanon and Winstrol. Side effects mostly observed by the AAS users were the appearance of acne (46 to 94%) and aggressiveness (47 to 73%). Conclusion: Both the use of DS and AAS are exacerbated in the gyms of Brazil, mainly in the Southeast. In addition, the abuse of AAS is due to a lack of information about their contraindications, resulting in innumerous adverse health effects.

Beta 2 agonistas en deportistas. ¿Una ayuda ergogénica? / Beta 2 agonists in athletes. An ergogenic aid?

El asma es una condición crónica de las vías aéreas con hiperreactividad bronquial y broncoconstricción. El ejercicio puede desencadenar los síntomas asmáticos, lo que se conoce como broncoespasmo inducido por el ejercicio (BIE). El asma es común en atletas olímpicos, por lo cual los deportistas utilizan los medicamentos β2 agonistas para prevenir y tratar los episodios de asma. Estos fármacos se suministran preferiblemente por inhalación. En el deporte, los β2 agonistas están restringidos por la regulación antidopaje, con base en que estos medicamentos tienen el potencial de mejorar el rendimiento físico, lo que puede resultar en una ventaja competitiva. Los β2 agonistas están prohibidos por la WADA (World Anti-doping Agency), con excepción del salbutamol (con suministro máximo permitido de 1.600 µg en 24 horas) y el salmeterol inhalado. Estos fármacos, administrados por vía oral, pueden tener efectos ergogénicos en los deportistas. Se ha documentado que administrado por esta vía el salbutamol puede mejorar el rendimiento en disciplinas de resistencia, aumentar la fuerza muscular y mejorar la potencia anaeróbica. Sin embargo, según la evidencia científica, los β2 agonistas inhalados no tienen un efecto relevante de aumento en el rendimiento en deportistas no asmáticos.

Asthma is a chronic disorder of the airways with bronchial hyperresponsiveness and bronchoconstriction. Exercise can trigger asthma symptoms; this condition is known as exerciseinduced bronchospasm (EIB). Asthma is common in Olympic athletes who therefore use β2 agonists to prevent and treat its episodes. These drugs are preferably supplied by inhalation. In sports, the use of β2 agonists is restricted by anti-doping regulation, arguing that these drugs have the potential to improve physical performance, which can result in a competitive advantage. β2 agonists are prohibited by the WADA (World Anti-Doping Agency), except salbutamol (maximum dose: 1.600 µg over 24 hours) and salmeterol. Oral administration of salbutamol can induce ergogenic effects in athletes. It has been documented that when given orally β2 agonists can improve performance in endurance disciplines, increase muscle strength and improve anaerobic power. However, according to scientific evidence, inhaled β2 agonists do not have a relevant performance-enhancing effect in nonasthmatic athletes.

Suplementação com creatina altera a potência no teste de Wingate mas eleva a concentração de creatinina / Creatine supplementation alters power in the Wingate test but increases creatinine concentration

O objetivo deste estudo foi verificar o efeito da suplementação de creatina sobre o desempenho nos testes de Wingate de 10 e 30 segundos além da sua influência na concentração de lactato, ureia, creatinina e massa corporal de indivíduos fisicamente ativos. Para realização da pesquisa foram selecionados nove voluntários, sendo divididos dentro de dois grupos utilizando o procedimento duplo-cego: grupo creatina (n = 4) e grupo placebo (n = 5). A suplementação foi realizada via oral durante 10 dias, sendo que o grupo creatina ingeriu 20g de creatina (4x ao dia) nos primeiros cinco dias, seguida de uma ingesta de 5g/dia até o 10º dia. O grupo placebo recebeu a mesma dosagem, porém de maltodextrina como placebo. O protocolo de teste realizado antes e após o período de suplementação constou de um teste de Wingate adaptado de 10 segundos, seguido de um intervalo de 20 minutos para aplicação de um teste de Wingate de 30 segundos. Foram coletadas amostras de sangue antes e após o período de suplementação para análise de creatinina e ureia, lactato em repouso, 90 segundos após o teste de 10 segundos e 180 segundos após o teste de 30 segundos. A suplementação de creatina promoveu um aumento significativo (p < 0,05) na potência máxima durante o teste de 30 segundos, na potência média no teste de 10 segundos, além da concentração de creatinina. Os resultados sugerem que a suplementação de creatina pode melhorar o desempenho dos indivíduos durante exercício de alta intensidade e curta duração realizado no cicloergômetro, mas produz aumento da concentração de creatinina em repouso.

The aim of this research was to verify the effect of the creatine supplementation on performance in the 10 and 30-second Wingate tests, besides its influence in the creatinine, urea and lactate concentration and body mass of physically active men. This research selected nine volunteers, who were then separated in two groups using the double-blind procedure: creatine group (n=4) and placebo group (n=5).The supplementation was orally administered during ten days. The creatine group ingested 20g of creatine (4 times a day) in the first five days, followed by an ingestion of 5 g/day until the tenth day. The placebo group received the same dosage, but of maltodextrine instead, as placebo. The test protocol performed before and after the supplementation period consisted of an adapted 10-second Wingate test, followed by an interval of 20 minutes for application of the 30-second Wingate test .Blood samples were collected before and after the supplementation period for analysis of creatinine and urea, lactate at rest, 90 seconds after the 10-second test and 180 seconds after the 30-second test. Creatine supplementation promoted significant raise (p<0.05) in maximal power output during the 30-second test, in the mean power output in the 10 second-test, besides the creatinine concentration. The results suggest that creatine supplementation can improve individual performance in high intensity activities and short duration made in cycle ergometer; however, creatine supplementation increases the creatinine concentration at rest.

Efeitos da suplementação com creatina e cafeína sobre a força de fratura óssea em ratos submetidos a exercício de saltos verticais / Effects of creatine and caffeine supplementation on the bone breaking force in rats subjected to vertical jumping exercise

Este estudo investigou se a suplementação com creatina e cafeína, isoladamente ou combinadas, interfere na força de fratura óssea em ratos jovens exercitados. Os ratos foram divididos aleatoriamente em oito grupos: sedentários placebo, exercitado placebo, sedentário creatina, exercitado creatina, sedentário cafeína, exercitado cafeína, sedentário creatina + cafeína e treinado creatina + cafeína. Os grupos suplementados receberam creatina (carga: 0,430g/kg de peso corporal, por sete dias; e manutenção: 0,143g/kg, por 35 dias), cafeína (10mg/100g de peso corporal, por 35 dias) ou creatina+cafeína. Os grupos exercitados executaram saltos verticais na água (4x10 saltos com 1 minuto de intervalo entre séries, 5 dias/sem) por seis semanas. A ingestão de cafeína reduziu a espessura, o peso e a força de fratura do fêmur dos ratos, independentemente do exercício. A cafeína e a creatina+cafeína aumentaram a excreção urinária de cálcio. O exercício de saltos elevou a força de fratura, independentemente da suplementação, mas não alterou o peso e as dimensões do fêmur dos animais.

This study investigated whether supplementation with high doses of creatine and caffeine, alone or in combination, affects the bone breaking force of exercised rats. Rats were randomly divided into 8 groups: Sedentary or Exercised (placebo, creatine, caffeine or creatine plus caffeine). The supplemented groups received creatine (load: 0.430 g/kg body weight, for 7 days; and maintenance: 0.143 g/kg for 35 days), caffeine (10 mg/100g body weight, for 35 days) or creatine plus caffeine. The exercised groups underwent a vertical jump training in water (4 sets of 10 jumps interspersed with 1 min resting intervals, 5 days/wk), for 6 weeks. Caffeine ingestion reduced the femur´s width, weight and breaking force, independently of exercise. Caffeine and creatine plus caffeine increased the urinary calcium excretion. Jumping exercise increased the bone breaking force independently of supplementation; nevertheless it did not change the weight and dimensions of the femur of the animals.

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..

Enxágue bucal com carboidrato: recurso ergogênico capaz de otimizar o desempenho físico / Carbohydrate mouth rinse: an ergogenic aid able of optimizing the performance

Alguns estudos têm demonstrado que a simples presença de carboidrato na boca humana pode favorecer a ativação de algumas regiões cerebrais específicas com impacto positivo para a melhoria do desempenho físico. Assim, recentemente, a estratégia de enxágue bucal com carboidrato tem sido adotada com sucesso em exercícios físicos intensos (>70%VO2max) com duração de, aproximadamente, 60 min. Nesse sentido, o propósito deste estudo foi discutir, com base nas informações disponíveis na literatura, a eficácia ou não da estratégia de enxágue bucal com carboidrato para a melhoria do desempenho físico, bem como os possíveis mecanismos envolvidos. Os resultados produzidos, embora ainda preliminares, são bastante promissores, o que nos leva a acreditar que o enxágue bucal com carboidrato possa ser uma estratégia bastante interessante, sobretudo, pela fácil aplicabilidade, baixo custo e boa eficácia para a melhoria do desempenho físico em esforços físicos intensos e prolongados.

Studies have shown that the mere presence of carbohydrate in the human mouth promotes the activation of some specific brain regions, with a positive impact on physical performance. Thus, the strategy of carbohydrate mouth rinse has been recently adopted with success in strenuous exercise (> 70% VO2max) lasting approximately 60 min. In this respect, the objective of this study was to discuss, based on literature data, the efficacy of this strategy to improve physical performance, as well as the possible mechanisms involved. The results produced, although still preliminary, are promising and led us to believe that carbohydrate mouth rinse is an interesting strategy, especially because of its easy application, low cost and good efficacy in improving physical performance during intense and prolonged physical exercise.

Influência da suplementação aguda e crônica de creatina sobre marcadores enzimáticos de dano muscular de ratos sedentários e exercitados com natação / Influence of short and long term creatine supplementation on enzymatic markers of muscle damage in sedentaries and exercised rats

O objetivo deste estudo foi investigar os efeitos da suplementação aguda (5 g.kg-1 durante uma semana) e crônica (1 g.kg-1 durante quatro e oito semanas) de creatina (Cr) sobre as concentrações plasmáticas de Creatina Quinase (CQ), Lactato Desidrogenase (LDH) e Aspartato Aminotransferase (AST), de ratos sedentários e exercitados (natação a 80 por cento da carga máxima tolerada). Setenta e dois ratos Wistar machos (250 ± 10 g) foram utilizados e divididos igualmente em quatro grupos: ratos sedentários não suplementados (CON; n = 18); ratos exercitados não suplementados (NAT; n = 18); ratos sedentários e suplementados (CRE; n = 18); ratos exercitados e suplementados (CRE + NAT; n = 18). Ao final da primeira, quarta e oitava semanas, seis animais de cada grupo foram sacrificados. Os resultados demonstraram: 1) ao final da primeira semana elevação plasmática de CQ, LDH e AST nos grupos NAT-1 e CRE+NAT-1 em relação aos grupos CON-1 e CRE-1; 2) ao final da quarta semana valores superiores para CQ e LDH somente no grupo NAT-4; e 3) ao final da oitava semana, somente os valores de AST do grupo CRE-8 diferiram dos demais. Estes achados sugerem que a suplementação de Cr: 1) não afeta o dano muscular em ratos submetidos a uma semana de treinamento físico de alta intensidade em meio aquático; 2) pode ser capaz de reduzir o dano muscular após quatro semanas de treinamento; e 3) após oito semanas de suplementação de Cr, o dano muscular parece ser atenuado pelo próprio exercício, anulando os efeito da Cr.

The aim of this study was to investigate the effects of the short-term (5 g.kg-1 to 1 week) and long-term (1 g.kg-1 to 4-8 weeks) creatine supplementation (Cr) on the Creatine Kinase (CK), Lactate Dehydrogenaze (LDH) and Aspartate Aminotransferase (AST) plasmatic concentrations of sedentary and exercised (swimming to 80 percent of the tolerated maximum load) rats. Seventy two Wistar males rats (250 ± 10 g) were equally divided in four groups: sedentary rats without supplementation (CON; n = 18); exercised rats without supplementation (NAT; n = 18); sedentary rats with supplementation (CRE; n = 18); exercised rats with supplementation (CRE+NAT; n = 18). At the end of the first, fourth and eighth weeks six animals of each group were sacrificed. The results demonstrated: 1) improvement of CK, LDH and AST in NAT-1 and CRE+NAT-1 groups vs. CON-1 and CRE-1 groups after the first experimental week; 2) higher values of CK and LDH only NAT-4 group after four experimental weeks; and 3) only AST from CRE-8 group differed from other groups at the end of the eighth experimental week. These findings suggest that the Cr supplementation: 1) does not affect the muscle damage on swimming exercised rats after one week of high intensity training; 2) could be able to reduce the muscle damage after 4 weeks of training; and 3) after eight weeks of Cr supplementation, the muscle damage seems to be attenuated by the exercise, nullifying the effects of Cr.