To analyze the singing voice handicap index in elderly choristers and verify its relationship with the profile, habits and health conditions of the participants.110 individuals aged 60 years or older, participating in amateur choirs, were included. Choir singers were interviewed in order to verify data such as age, time in choir singing, vocal classification, and the presence of habits and health conditions adverse to voice production. Subsequently, they answered the questionnaire “Singing Voice Handicap Index (SVHI)”, which assesses the individual's self-perception in relation to experiences in the use of the singing voice.The SVHI score had a median of 25, with a minimum score of 0 and a maximum score of 86. The most scored items were related to physical aspects in the use of singing voice: “I am unable to use my ‘high voice’” (Q10) and “My throat is dry when I sing”(Q13). It was found that older adults over 75 years of age had a greater voice handicap when compared to younger ones (p=0.020). Choir singers classified as contralto also had a higher SVHI score (p=0.023), as well as individuals who reported drinking little water (p=0.007).The choristers in this study presented a singing voice handicap index compatible with healthy singing voices. When verifying the relationship of the SVHI score with the characteristics of the participants and with respect to habits and health conditions, it was found that the elderly choir singers over 75 years old, the contralto choir singers, and those who claimed to drink little water had higher scores for the singing voice handicap. Common symptoms associated are breathiness, hoarseness, loudness changes, the increase in pitch for men and decrease for women, instability, and greater effort during phonation. When comparing the voices of elderly singers and non-singers, studies show that the first group has fewer voice quality changes, greater vocal range, and longer maximum phonation times-7.The vocal changes resulting from aging are, however, more subtle in individuals who sing, since frequent singing acts as a moderator of the negative effects related to this process-10. Aging is a natural process, and even in elderly people with a healthy and vocally active lifestyle, anatomical, physiological and functional changes over time can cause vocal difficulties.The practice of choral singing has many physical and psychosocial benefits for the elderly, but it also requires that the systems involved with phonation can meet the demand for vocal use for singing in order to avoid generating overload to the phonatory system, muscle compensation, and increased risk of laryngeal lesions,12.In addition, the lack of knowledge and technique contributes to the inappropriate use of the voice and the worsening of voice-related signs and symptoms. Singers often present vocal tract dryness, fatigue, discomfort, pain, tightness in the throat, tension, vocal breaks, and voice loss, impacting the quality of life of these individuals,3. The present study sought to analyze the singing voice handicap index of elderly chorus singers and to verify its relationship with the profile, habits and health conditions of the participants.Therefore, the identification of situations that generate voice disadvantages for singing and related factors allows a preventive speech therapy action to be performed through more effective guidance, which in turn enhances the effects of singing for the vocal health of this populationThis is a prospective cross-sectional study, approved by the Research Ethics Committee, under number 1.981.615. Nine amateur choirs from a city in the southern region of the country were contacted and, under the authorization of the person responsible for each of them, the research project was presented during the group rehearsal. Interested choristers were individually interviewed and invited to participate in the study by signing the Informed Consent Form (ICF). Individuals aged over 60 years and who participated in the choir for at least one year were included. Individuals who smoked and those who reported having undergone speech therapy prior to or simultaneously with the study were excluded from the study. and translated by Behlau and Gasparini The SVHI consists of 36 questions related to the impact on physical, emotional, social and economic aspects of vocal problems in singing. For each item, there are five response options “Never”, “Almost Never”, “Sometimes”, “Almost Always” and Always, scored from 0 to 4, respectively. The total score can range from 0 to 144. This considers the minimum value being the lowest voice handicap index, and the maximum value being the highest voice handicap index. The scale does not have domains and subscales. Choir singers answered the questionnaire individually before or after the rehearsal in the time necessary for each one and if they had any doubts about any question, they could ask the researchers for help. The items in the questionnaire which scored more or less were then verified.The elderly singers were invited to answer the questionnaire entitled “Singing Voice Handicap Index” (SVHI), developed and validated by CohenThe following data were collected through interviews: age, gender, education, vocal classification, and time in choral singing. The vocal classification had previously been determined by the conductor of each choir. The choristers were also asked about their habits and health conditions. Questions were asked about the practice of physical activity, water consumption, frequent and prolonged use of the voice, hearing difficulties, respiratory allergies, gastroesophageal reflux, throat clearing, excessive consumption of caffeinated beverages, distilled beverages, and sleep, totaling ten questions. Each question could be answered with “yes” or “no”, receiving a point for each answer unfavorable to general and vocal health, which could add up to 10 points. The data collection was carried out from April 2017 to October 2018.The Statistical Package for the Social Sciences (SPSS) version 19.0 was used for database configuration and statistical analysis. Kolmogorov-Smirnov tests were performed to analyze the normality of variance. Continuous variables were described using the median and interquartile range, and categorical variables using absolute and relative frequency. The Mann-Whitney U test was used to compare the total score of the SVHI between the variables age, sex, and for each of the habits and health conditions. The Kruskal-Wallis test was used to compare the total score of the SVHI between levels of education, vocal classification, and time in choral singing. Spearman's correlation was also verified between the total score of the SVHI and age, time in choral singing, and scores related to habits and health conditions. Values of p<0.05 were considered statistically significant.Of the 115 choristers interviewed, five were excluded from the sample. One for being a smoker and four for having undergone speech therapy previously.The sample had a total of 110 choristers, with a predominance of females (74.5%). The age range varied from 60 to 91 years of age, with a median of 69 (10). Most seniors were up to 75 years of age (77.3%). Higher education and/or graduate education was the most prevalent (69.1%) followed by high school (24.5%). The predominant time of choral singing was greater than 10 years (44.5%). In the composition of the sample, the singers were classified as soprano (39.1%), contralto (33.6%), tenor (18.2%), and bass (9.1%).The singing voice handicap index had a median of 25(25) with a minimum score of 0 and a maximum score of 86. According to The values of the questionnaire according to the characteristics of the participants can be seen in As for habits and health conditions, 23 (20.9%) reported not practicing any type of physical activity and 75 (68.2%) claimed to consume little water. In addition, 70 (63.6%) reported that they talk a lot, 52 (47.3%) that they slept little, 33 (30%) that they consumed caffeine in excess, and 22 (20%) distilled beverages. It was also identified that 37 (33.6%) had hearing difficulties, 47 (42.7%) had respiratory allergies, 32 (29.1%) had gastroesophageal reflux and 36 (32.7%) had frequent throat clearing. The relationship between the median of the SVHI score for each answer regarding habits and health conditions, represented by the p-value, is described in There were positive correlations, although considered weak, between the total score of the SVHI and the age variable, as well as for the score of the habits and health conditions questionnaire, as can be seen in . The score was also similar to the mean normative value of a group of 729 singers healthy professionals aged between 18 and 64 years, published in a recent systematic review, who presented an SVHI of 20.35 with a confidence interval between 10.6 and 30.1. Studies that have validated the protocol in different languages have shown that it is a valid and reliable method for identifying the individual's self-perception concerning the impact of vocal problems in singing-21.The choristers in this study presented an SVHI score compatible with healthy voices for singing, as found by Cohen (2007) in the validation of the instrument used This study used the questionnaire “Modern Singing Handicap Index” (MSHI) and specific questionnaires for vocal symptoms and to assess anxiety. MSHI, like SVHI, is adapted for singing voice, but this one specifically for modern singing. It is divided into three subscales: disability, handicap, and defect, which correspond respectively to the functional, emotional, and organic domains, which makes it possible to identify which domain the singer has the greatest disadvantage for singing. The SVHI, despite addressing these domains in its questions, does not measure them separately, that is, it does not have subscales. However, when which questions had the highest frequency was verified, it was observed that those related to physical/functional aspects were more frequent compared to the others.Items related to physical/functional problems were scored higher than those related to social/emotional aspects, results that can be compared to those of a study that evaluated 526 amateur chorus singers and found the presence of vocal symptoms but with a mild level of anxiety., a relation verified in the present study and which found that the SVHI score of the choir singers was significantly higher in the elderly over 75 years old compared to younger ones. These results suggest that increasing age contributes to a greater occurrence of problems in the use of singing voice, especially those related to physical aspects,13,22.A study that used the SVHI to assess 171 singers found that age is an important predictive factor for the greatest handicap in the use of singing voice.On the other hand, the frequent habit of singing has a moderating effect on the vocal aging process. A study that evaluated 72 healthy adults found that singing helps to maintain pitch and amplitude stability, two important factors for effective communication. The authors also suggest that singing, representing muscle training, would help to maintain strength and control over vocal stability even in the presence of age-related changes. Although this study did not show the correlation between choir singing time and a lower rate of vocal handicap, another study highlighted the inversely proportional association in the scores of three singing protocols applied with the period of singing voice development. This shows that voices trained for a longer time may have fewer vocal symptoms when they are well oriented. The speech therapy work is of fundamental importance for the development of the elderly's vocal and auditory perception, as it will provide vocal skills necessary for the practice of choral singing, such as directed vocal techniques and increased vocal range, observing the physiological aspects involved in the voice production of the elderly chorus singers,8,20.The practice of singing, when oriented, is shown to be a protective factor for vocal quality for both professional and amateur singers and had greater vocal fatigue. In the present study, the most scored SVHI questions describing the main difficulties of the contralto choir singers, in addition to reaching the high notes, are related to the control of their voice and breathiness during singing, which instigates the hypothesis that these choir singers are under a greater effect of presbyphonia. It is questioned, therefore, whether the elderly contraltos are allocated in this vocal classification due to individual vocal characteristics or because they present more evident signs of the aging process in the voice, which would result in a deeper vocal quality,26.In the comparison between the vocal classifications, the study showed that there is a statistically significant difference in the total score of the SVHI, with the elderly female contraltos having a greater vocal handicap for singing than the sopranos. This fact is in agreement with other studies, in which the contralto choir singers had higher scores in the handicap for singing,27.A positive, albeit weak, correlation was found between the questionnaire on vocal habits and health conditions and the SVHI protocol, suggesting that the more harmful habits and health conditions adverse to vocal production the individual has, the greater will be their singing voice handicap. The vocal and health habits of the choir singers are essential factors for the proper functioning of the phonatory system and for singing performance, being important items in the assessment and speech therapy intervention of these individuals,29, especially for the voice of elderly people who sing. In another study, water intake was also more prevalent in elderly choristers than in non-choristers, denoting that singing requires a higher level of hydration due to its importance for the balance of the phonatory system in emission. of the singing voice. This is a simple habit because it is accessible to most of the population, but it contributes considerably to the reduction of vocal complaints. This may be because it favors the flexibility, vibration, and lubrication of the vocal folds and, consequently, helps to maintain the biodynamic balance of the mechanisms involved in vocal production.The findings suggest that the habit of drinking water was correlated with a lower vocal handicap for singing, confirming the benefit of hydration for vocal function also observed in other studies. However, for the variable gender, it is possible to verify in the literature, a greater vocal handicap in female singers, as well as in non-singers, is mainly related to the functional aspects of voice use. As for GER and respiratory allergies, it is known that when present, they can impair vocal production. Our study did not detect these effects based on the SVHI score, possibly because the investigation was based on self-reported symptoms by the participants and not verified through objective examinations or medical history.In this study, no significant differences were observed in the SVHI scores associated with GER, respiratory allergies, and gender, which is in line with other research related to factors associated with a singing handicapThe other variables on habits and health conditions did not show a significant relationship with the SVHI score, even those known to be adverse to the voice. Most likely due to the methodology of the applied questionnaire, which addressed only “Yes” or “No” questions, not evaluating the frequency or duration of these variables in the routine of the elderly who participated in the study.Regarding the limitations of the study, the absence of laryngeal image assessments to detect possible alterations in the structures of the vocal tract and the lack of specificity of the SVHI instrument for application in elderly populations stand out. In this sense, further studies are suggested that consider the otorhinolaryngological assessment and the construction of an instrument that identifies vocal characteristics and specific difficulties of populations of elderly choristers.The study showed a median of 25(25) in the protocol's total score, positive associations with age and vocal classification, in addition to a positive correlation with vocal habits. We highlight the importance of using vocal self-perception instruments and vocal health questionnaires in amateur choirs, in order to map possible difficulties presented by this population, enabling a speech therapy intervention based on the choir's needs. In future studies, we suggest the adaptation of the instrument for application to elderly choristers, aiming to meet the specificities and demands involved in the activity of choral singing at this stage of life.The choristers in this study presented a singing voice handicap index compatible with healthy singing voices. When verifying the relationship of the SVHI score with the characteristics of the participants and with respect to habits and health conditions, it was found that the elderly choir singers over 75 years old, the contralto choir singers, and those who claimed to drink little water had higher scores of voice handicap for singing. loudness, o aumento do pitch para os homens e diminuição para as mulheres, instabilidade e o maior esforço durante a fonação-3.As alterações da voz podem surgir em qualquer idade por motivos diversos, porém, no decorrer do envelhecimento há um processo natural e gradual da perda da eficiência vocal conhecido como presbifonia, tendo como sintomas comuns, a presença de soprosidade, rouquidão, alterações de . Ao comparar as vozes de idosos cantores e não cantores, os estudos demonstram que o primeiro grupo apresenta menos alterações de qualidade vocal, maior extensão vocal e tempos máximos de fonação mais longos-7.As alterações vocais decorrentes do envelhecimento apresentam-se, no entanto, mais sutis em indivíduos que cantam¸ uma vez que o canto frequente atua como um moderador dos efeitos negativos relacionados a esse processo-10. O envelhecimento é um processo natural e mesmo em idosos com um estilo de vida saudável e vocalmente ativos, as modificações anatômicas, fisiológicas e funcionais ao longo do tempo, podem gerar dificuldades e desvantagens vocais.A prática do canto coral apresenta muitos benefícios físicos e psicossociais ao indivíduo idoso, mas também exige que os sistemas envolvidos com a fonação consigam suprir a demanda do uso vocal para o canto para que evitem gerar sobrecargas ao aparelho fonador, compensações musculares e o aumento do risco de ocorrer lesões laríngeas,12.Além disso, a falta de conhecimento e técnica contribuem para o uso inapropriado da voz e para o agravamento dos sinais e sintomas relacionados à voz. Os cantores apresentam frequentemente ressecamento do trato vocal, fadiga, desconforto, dor, sensação de aperto na garganta, tensão, quebras vocais e perda da voz, impactando a qualidade de vida destes indivíduos,3. O presente estudo buscou analisar o índice de desvantagem vocal para o canto de coristas idosos e verificar a sua relação com perfil, hábitos e condições de saúde dos participantes.Portanto, a identificação de situações que geram desvantagens vocais para o canto e de fatores relacionados permite que seja realizada uma atuação fonoaudiológica preventiva por meio de orientações mais efetivas, que por sua vez potencializem os efeitos do canto para a saúde vocal a esta populaçãoTrata-se de um estudo transversal prospectivo, aprovado pelo Comitê de Ética em Pesquisa, sob o número 1.981.615. Foram contatados nove coros amadores de uma cidade da região sul do país e sob a autorização do responsável por cada um deles, o projeto de pesquisa foi apresentado durante o ensaio dos grupos. Os coristas interessados foram entrevistados e convidados individualmente a participar da pesquisa por meio da assinatura do Termo de Consentimento Livre Esclarecido (TCLE). Foram incluídos os indivíduos com idade igual ou maior que 60 anos e que participavam do coro por pelo menos um ano. Foram excluídos da pesquisa os indivíduos tabagistas e aqueles que declararam ter realizado acompanhamento fonoaudiológico anterior ou simultâneo ao estudo. e traduzido por Behlau e Gasparini. O IDV-C é composto por 36 questões relacionadas com o impacto nos aspectos físico, emocional, social e econômico dos problemas vocais no canto. Para cada item, há cinco opções de respostas “Nunca”, “Quase nunca”, “Às vezes”, “Quase sempre” e Sempre, pontuadas de 0 a 4, respectivamente. O escore total pode variar de 0 a 144, sendo considerado o valor mínimo, o menor índice de desvantagem vocal e o valor máximo, o maior índice de desvantagem vocal. A escala não possui domínios e subescalas. Os coristas deveriam responder o questionário individualmente antes ou após o ensaio no tempo necessário para cada um e caso tivessem dúvidas em relação à alguma questão, poderiam solicitar auxílio aos pesquisadores. Foi verificado quais foram os itens do questionário mais ou menos pontuados.Os idosos foram convidados a responderem o questionário intitulado “Índice Desvantagem Vocal para o Canto” (IDV-C), elaborado e validado por CohenForam coletados, por meio de entrevista, os seguintes dados: idade, sexo, escolaridade, classificação vocal e tempo de canto coral. A classificação vocal já havia sido determinada anteriormente pelo regente de cada coro. Os coristas foram questionados também a respeito dos seus hábitos e condições de saúde. Foram realizadas perguntas sobre a prática de atividade física, consumo de água, uso frequente e prolongado da voz, dificuldade auditiva, alergias respiratórias, refluxo gastroesofágico, pigarro, consumo excessivo de bebidas com cafeína, bebidas destiladas e sono, totalizando dez questões. Cada pergunta poderia ser respondida com “sim” ou “não”, recebendo um ponto a para cada resposta desfavorável à saúde geral e vocal, podendo somar 10 pontos. A coleta foi realizada no período de abril de 2017 a outubro de 2018.Statistical Package for the Social Sciences (SPSS) versão 19.0 para configuração do banco de dados e análise estatística. Foram realizados os testes de Kolmogorov-Smirnov para a analisar a normalidade de variância. As variáveis contínuas foram descritas por meio da mediana e intervalo interquartil e as categóricas por meio da frequência absoluta e relativa. Foi utilizado o teste de U de Mann-Whitney para comparar o escore total do IDV-C entre as variáveis idade, sexo e para cada um dos hábitos e condições de saúde. O teste de Kruskal-Wallis foi utilizado para comparar o escore total do IDV-C entre os níveis de escolaridade, classificação vocal e tempo de canto coral. Verificou-se também a correlação de Spearman entre o escore total do IDV-C e a idade, tempo de canto coral e pontuação relacionada aos hábitos e condições de saúde. Foram considerados estatisticamente significativos os valores de p<0,05.Foi utilizado o Foram entrevistados 115 coristas. Destes, cinco foram excluídos: uma por ser fumante e quatro por terem realizado tratamento fonoaudiológico prévio.A amostra teve um total de 110 coristas, com predomínio do sexo feminino . A faixa etária variou entre 60 a 91 anos de idade, tendo como mediana 69 (10). A maioria dos idosos apresentavam até 75 anos de idade . O grau de escolaridade de ensino superior e/ou pós-graduação foi o mais predominante  seguido do ensino médio . O tempo de canto coral predominante foi maior que 10 anos . Na composição da amostra, os coristas foram classificados como soprano , contralto , tenor  e baixo .O índice de desvantagem vocal para o canto teve uma mediana de 25(25) sendo a pontuação mínima 0 e a máxima 86. Conforme o Os valores do questionário de acordo com as características dos participantes podem ser observados na Quanto aos hábitos e condições de saúde, 23  relataram não praticar nenhum tipo de atividade física e 75  afirmaram consumir pouca água. Além disso, 70  informaram que falam em grande quantidade, 52  que dormiam pouco, 33 (30%) que consumiam bebidas com cafeína em excesso e 22 (20%) bebidas destiladas. Foi identificado também que 37  apresentavam dificuldade auditiva, 47  alergias respiratórias, 32  refluxo gastroesofágico e 36  pigarro. A relação entre a mediana do escore do IDV-C para cada resposta a respeito dos hábitos e condições de saúde, representada pelo valor p, estão descritas na Houve correlações positivas, embora consideradas fracas, entre o escore total do IDV-C e a variável idade, bem como para a pontuação do questionário de hábitos e condições de saúde como pode ser observada na . O escore também foi semelhante ao valor normativo médio de um grupo de 729 cantores profissionais saudáveis com idade entre 18 e 64 anos, publicado em uma revisão sistemática recente, que apresentaram um IDV-C de 20,35 com intervalo de confiança entre 10.6 e 30.1. Estudos que validaram o protocolo em diversos idiomas demonstraram que é um método válido e confiável na identificação da autopercepção do indivíduo em relação ao impacto dos problemas vocais no canto-21.Os coristas deste estudo apresentaram um escore de IDV-C compatível com vozes saudáveis para o canto, como encontrado por Cohen (2007) na validação do instrumento utilizado. Este estudo utilizou o questionário “Índice de Desvantagem para o Canto Moderno” (IDCM) e questionários específicos para os sintomas vocais e para avaliar a ansiedade. O IDCM, assim como o IDVC, é adaptado para a voz cantada, mas este especificamente para o canto moderno. É dividido em três subescalas: incapacidade, desvantagem e defeito, que correspondem respectivamente aos domínios funcional, emocional e orgânico, o que possibilita identificar qual o domínio que o cantor apresenta maior desvantagem para o canto. O IDVC, apesar de abordar os referidos domínios em suas questões, não as mensura separadamente, ou seja, não apresenta subescalas. Entretanto, quando foi verificado quais questões obtiveram maior frequência, observou-se que aquelas relacionadas aos aspectos físicos/funcionais foram mais frequentes comparadas às demais.Os itens relacionados a problemas físicos/funcionais foram mais pontuados do que os relacionados aos aspectos sociais/emocionais, resultados que podem ser comparados aos de um estudo que avaliou 526 coristas amadores e constatou a presença de sintomas vocais, mas com um índice leve de ansiedade, relação verificada no presente estudo e que constatou que o escore do IDV-C dos coristas foi significativamente maior nos idosos com mais de 75 anos comparado aos mais jovens. Estes resultados sugerem que o aumento da idade contribui para a maior ocorrência de problemas no uso da voz cantada, especialmente aqueles relacionados aos aspectos físicos,13,22.Um estudo que utilizou o IDV-C para avaliar 171 cantores verificou que a idade é um fator preditivo importante para a maior desvantagem no uso da voz cantadapitch e de amplitude, dois fatores importantes para a efetividade da comunicação. Os autores sugerem ainda que o canto, representando um treino muscular, ajudaria a manter a força e controle sobre a estabilidade vocal mesmo na presença das alterações decorrentes da idade.Por outro lado, o hábito frequente de cantar apresenta um efeito moderador do processo de envelhecimento vocal. Um estudo que avaliou 72 adultos saudáveis verificou que o canto auxilia na manutenção da estabilidade de . Embora este estudo não tenha evidenciado a correlação do tempo de canto coral ao menor índice de desvantagem vocal, outra pesquisa destacou a associação inversamente proporcional nos escores de três protocolos de canto aplicados com o período de desenvolvimento da voz cantada, evidenciando que as vozes treinadas por mais tempo podem ter menos sintomas vocais quando são bem orientadas. É de fundamental importância o trabalho fonoaudiológico para o desenvolvimento da percepção vocal e auditiva dos idoso, visto que irá proporcionar habilidades vocais necessárias para a prática do canto coral, como técnicas vocais direcionadas e aumento da tessitura vocal, observando os aspectos fisiológicos envolvidos na produção da voz do idoso corista,8,20.A prática do canto quando orientada mostra-se ser um fator de proteção da qualidade vocal tanto para cantores profissionais, quanto amadores e apresentaram maior cansaço vocal. No presente estudo, as perguntas do IDV-C mais pontuadas e que descrevem as principais dificuldades das coristas contralto, além do alcance às notas agudas, estão relacionadas ao controle da própria voz e da soprosidade durante o canto, o que instiga a hipótese de que estas coristas estejam sob maior efeito da presbifonia. Questiona-se, portanto, se as contraltos idosas estão alocadas nessa classificação vocal devido às características vocais individuais ou por apresentarem sinais mais evidentes do processo de envelhecimento na voz, o qual acarretaria numa qualidade vocal mais grave,26.Na comparação entre as classificações vocais, o estudo mostrou que há uma diferença estatisticamente significativa do escore total do IDV-C, tendo as idosas contraltos apresentado maior desvantagem vocal para o canto do que as sopranos. Esse fato concorda com outros estudos, nos quais as coristas contralto tiveram maiores escores na desvantagem para o canto,27.Foi encontrada uma correlação positiva, embora fraca, entre o questionário de hábitos vocais e condições de saúde e o protocolo IDV-C, sugerindo que quanto mais hábitos nocivos e condições de saúde adversas à produção vocal o indivíduo possui, maior será a sua desvantagem vocal para o canto. Os hábitos vocais e de saúde dos coristas são fatores essenciais para o adequado funcionamento do sistema fonatório e para a performance no canto, sendo itens importantes na avaliação e intervenção fonoaudiológica destes indivíduos,29, especialmente para a voz do idoso que canta. Em outro estudo a ingestão de água também mostrou-se mais prevalente em idosas coristas do que nas não coristas, denotando que a prática do canto exige um maior nível de hidratação devido à sua importância para o equilíbrio do sistema fonatório na emissão da voz cantada. Este é um hábito simples por ser acessível a maioria da população, mas que contribui consideravelmente para a diminuição das queixas vocais, uma vez que favorece a flexibilidade, vibração e lubrificação das pregas vocais e, por consequência, ajuda a manter o equilíbrio biodinâmico dos mecanismos envolvidos na produção vocal.Os achados sugerem que o hábito de tomar água esteve correlacionado à menor desvantagem vocal para o canto, confirmando o benefício da hidratação para a função vocal observado também em outros estudos. No entanto para a variável sexo é possível verificar na literatura uma maior desvantagem vocal em mulheres cantoras, bem como em não cantoras relacionado, principalmente, aos aspectos funcionais do uso da voz. Quanto ao RGE e alergias respiratórias, sabe-se que quando presentes estes podem prejudicar a produção vocal. Nosso estudo não detectou esses efeitos a partir do escore do IDV-C, possivelmente, porque a investigação foi realizada com base nos sintomas auto-referidos pelos participantes e não verificados através de exames objetivos ou histórico médico.Nesse estudo não foram observadas diferenças significativas nos escores do IDV-C associadas ao RGE, alergias respiratórias e sexo, estando em consonância com outra pesquisa relacionada a fatores associados a desvantagem para o cantoAs demais variáveis sobre hábitos e condições de saúde não apresentaram relação significativa com a pontuação do IDV-C, mesmo as conhecidas adversas à voz. Provavelmente pela metodologia do questionário aplicado, que abordou questões somente de “Sim” ou “Não”, não avaliando a frequência e nem duração dessas variáveis na rotina dos idosos que participaram da pesquisa.Com relação às limitações do estudo, destacam-se a ausência de avaliação de imagem laríngea para a detecção de possíveis alterações de estruturas do trato vocal e a falta de especificidade do instrumento IDV-C para a aplicação em populações idosas. Neste sentido, sugere-se mais pesquisas que considerem a avaliação otorrinolaringológica e a construção de um instrumento que identifique características vocais e dificuldades específicas de populações de coristas idosos.O estudo demonstrou uma mediana de 25(25) na pontuação total do protocolo, associações positivas com idade e classificação vocal, além de uma correlação positiva com hábitos vocais. Destacamos a importância do uso de instrumentos de autopercepção vocal e de questionários de saúde vocal em coros amadores, a fim de mapear possíveis dificuldades apresentadas por esta população, possibilitando uma intervenção fonoaudiológica baseada nas necessidades do coro. Em estudos futuros, sugerimos a adaptação do instrumento para a aplicação em coristas idosos, visando atender às particularidades e às demandas envolvidas na atividade do canto coral nesta fase da vida.Os coristas deste estudo apresentaram um índice de desvantagem vocal para o canto compatível com vozes saudáveis para o canto. Ao verificar a relação do escore do IDV-C com as características dos participantes e a respeito dos hábitos e condições de saúde, constatou-se que os coristas idosos com mais de 75 anos, as coristas contralto e aqueles que afirmaram beber pouca água apresentaram escores maiores de desvantagem vocal para o canto.


Neste sentido, a avaliação do padrão circadiano da PA em pacientes internados no hospital, não consiste em uma das indicações do método, mesmo com o objetivo de estudar desfechos específicos.6 Para avaliação da DAC, foi utilizado o escore SYNTAX, bem estabelecido para este fim. E para avaliação da PA foi adotada monitorização clínica, através de dispositivo automático em monitores a beira leito. Tais medidas foram realizadas a cada hora, nos períodos diurno e noturno. Os autores estabeleceram um protocolo próprio, considerando as médias dos valores horários de PA para 9 períodos noturnos (23:00 h às 07:00 h) e 15 períodos diurnos (8:00 h às 22:00 h), obtendo-se um único valor médio de PA diurna e noturna. Quanto à definição de descenso (dipping) presente, ausente ou reverso, os parâmetros foram os mesmos utilizados na MAPA.No presente estudo transversal e prospectivo, Turan et al. tiveram como objetivo avaliar, em pacientes hospitalizados com síndrome coronariana aguda (SCA), a relação entre a doença arterial coronariana (DAC) e menor descenso noturno da PA.dipper) se apresentou como um preditor independente de alto escore SYNTAX.Dentre os resultados obtidos, pode-se destacar que os pacientes internados com SCA, hipertensos e sem descenso noturno apresentaram escore SYNTAX mais alto. Além disto, o número de pacientes com escores altos foi significativamente maior no grupo de hipertensos sem descenso noturno, em comparação com o grupo com descenso. Apesar de não poder se estabelecer efeitos de causalidade, por se tratar de um estudo transversal, na análise por regressão logística mutivariada, o status de hipertensão sem descenso noturno  and diastolic (DBP) in 24 hours, wakefulness and sleep, stand out.2 Specifically regarding the behavior of BP during sleep, it is already well established that the absence of nocturnal dipping has, independently, a significant impact on the increased cardiovascular risk.4 Other parameters that may have prognostic implications are early morning BP elevation and greater 24-hour BP variability.5It is well established that there are significant prognostic implications resulting from the abnormal behavior of some 24-hour blood pressure (BP) parameters obtained through Ambulatory Blood Pressure Monitoring (ABPM).Some recommendations are essential for the success of the ABPM exam, among them, the orientation for the patient to maintain their usual activities during the monitoring day. In this sense, assessing the circadian pattern of BP in hospitalized patients is not one of the indications of the method, even intending to study specific outcomes.6 To assess CAD, the SYNTAX score was used, which is well established for this purpose. And for BP assessment, clinical monitoring was adopted through an automatic device on monitors at the bedside. Such measurements were performed every hour, during the day and night. The authors established their own protocol, considering the averages of hourly BP values for 9 night periods (11:00 pm to 7:00 am) and 15 daytime shifts (8:00 am to 10:00 pm), obtaining a single mean daytime and nighttime BP value. Regarding the present, absent or reverse dipping definition, the parameters are the same used in the ABPM.In the present cross-sectional and prospective study, Turan T. et al. aimed to evaluate, in hospitalized patients with the acute coronary syndrome (ACS), the relationship between coronary artery disease (CAD) and lower nocturnal BP dips.Among the results obtained, it can be highlighted that hospitalized patients with ACS, hypertensive and without nocturnal dipping had a higher SYNTAX score. In addition, the number of patients with high scores was significantly higher in the group of hypertensive patients without nocturnal dipping compared to the group with dipping. Despite not being able to establish causality effects because it is a cross-sectional study, in the multivariate logistic regression analysis, the status of hypertension without nocturnal dipping (non-dipper) was presented as an independent predictor of a high SYNTAX score.7 It was shown that the absence of nocturnal dipping corresponded to an independent risk marker for CAD, with data obtained by ABPM in clinically stable patients, and elective coronary angiography.This is the first study to assess the behavior of nocturnal BP in hospitalized patients with ACS. However, another study published by Mousa et al. had already demonstrated an association between hypertension without dipping and significant CAD in men.6 In this sense, it is worth reinforcing the mention by the authors of the study by Xu T. et al., who demonstrated a good correlation between the traditional manual BP measurement with a sphygmomanometer and the 24-hour ABPM in the detection of hypertensive patients without nocturnal dipping, also in a hospital.8Some limitations, duly described by Turan T. et al., are very important in the present study's analysis. Among them, it stands out the lack of verification of the reproducibility of BP measurements and the clinical condition of the evaluated patients, which can be very different from the usual condition in everyday life.9 However, studies like this are important so that we have other alternatives in the circadian assessment of BP in the hospital environment and the study of its correlation with outcomes. New randomized studies assessing the method's reproducibility may provide greater support for clinical practice in a hospital environment.We know that ABPM is the gold standard for measuring BP, including the assessment of nocturnal dipping.


Varicose veins are a highly prevalent condition in the general population, generating variable reasons for consultation that can alter the patient’s quality of life, with prevalence and associated factors that vary in different series.To describe the epidemiological profile of patients who consulted for varicose veins by evaluating main symptoms and associated variables.Between 2019 and 2020, 1,136 patients attending vascular surgery consultation in a specialized outpatient center were evaluated. Demographic variables, presented symptoms, complications, and associated factors, such as body mass index, parity and family history, were recorded.A total of 1136 patients were evaluated (79.8% women and 20.2% men), with a mean age of 53.51 years. The presence of symptoms was similar in men and women; the most frequent complications were ulcer, varicorrhage, and superficial venous thrombosis. Most patients showed CEAP 1, 2 and 3 (n = 909) and more than half were overweight or obese (n = 679) with a predominance of those classified as C4. Sixty-nine per cent had a positive family history of varicose veins. There was no difference between severity of varicose veins and time working in the standing or sitting position, but there was a greater presence of C5 or C6 ulcer among patients standing for more than 4 hours.Describing the characteristics of patients with varicose veins helps to understand the disease and to focus efforts towards those who are more susceptible. The results of this research are similar to those found in other populations. Varicose veins are a frequent condition in primary healthcare visits and one of the most treated by vascular surgeons worldwide, producing an array of important symptoms and long-term complications that have an impact on health and quality of life, which also increase health expenses.This is a prospective, descriptive study that collected data from patients who attended a vascular surgery consultation at a vascular disease center in the city of Medellin, Colombia, from June 2019 to December 2020. Patients who consulted for varicose veins were asked about variables related to venous disease, and their responses were inserted into a database previously developed on Excel during the consultation, including demographic variables, related medical history, symptoms, previous treatments, complication, family history, habits, and clinical variables such as severity according to the clinical-etiological-anatomical-pathophysiological (CEAP) classification and body mass index (BMI). Of note, confinement due to the COVID-19 pandemic was implemented in 2020, which slowed data collection down, and only face-to-face consultations that could be performed in this period were considered.This study complied with guidelines on personal data management and with institutional ethical policies, being categorized as a non-hazardous investigation. Data were processed on SPSS software, version 22, using frequencies and percentages for categorical variables and mean and standard deviation (SD) for quantitative variables. The chi-squared was used to investigate the relationship between categorical variables, considering a statistical significance level of p < 0.05.This study was conducted in compliance with the Declaration of Helsinki and the Colombian law on ethics and investigation: Resolution 8430 of 1993, issued by the Ministry of Health and Social Protection of Colombia. The protocol was approved by the ethics committee of the research institution .Overall, 1,136 patients were evaluated, consisting of 911 women (80%) and 225 men (20%). Mean age was 53.51 years  for the general population, 54 (SD±12.25) years for women, and 51.32 (SD±13.39) for men, with no age difference between the two groups (p = 0.127). The age distribution between genders and other characteristics are presented in Furthermore, 891 (78.33%) patients were classified into grades from 2 to 6 of the CEAP clinical classification. C4 grade or higher was more frequent in men than in women, whereas C2 and C3 had a similar frequency in both sexes. The distribution of symptoms was similar between men and women, with difference only for the presence of ardor and pain, which predominated in women. Pain was the most reported symptom in both genders, followed by tiredness and ardor. Of the symptoms evaluated, there were gender differences only for burning sensation and pain, which predominated in women (p < 0.05).The population studies had a low prevalence of diabetes, hypothyroidism, constipation, and smoking, but there was a remarkably high prevalence of overweight and obesity (64%) in this population. However, no differences in nutritional status were found between men and women; conversely, a higher presence of C4 grade or greater was observed in patients with BMI above 25.Moreover, 69% (782 patients) had a family history of at least one parent with varicose veins, and 13.11% (149 patients) had both parents with varicose veins. Furthermore, 212 patients (19%) had developed one or more complications, the most common of which was ulcer, which was present in 91 patients (8%), followed by varicorrhage, present in 22 (2.1%). Also, 83 (7.9%) patients had a history of superficial venous thrombosis, 19 (1.08%) had a history of deep venous thrombosis, and 11 (1.04%) presented associated lymphedema. Only 2.6% had an active ulcer at the time of assessment.No differences were found in symptom distribution between genders and among age groups, except for tiredness, which predominate in patients older than 35 years in both groups . In women, there were differences in weight distribution by age groups, with overweight and obesity predominating among those older than 35 years, whereas men exhibited a similar distribution for all age groups .With regard to distribution according to clinical severity, most patients with advanced disease were older than 50 years of age, and most patients attended consultation with C2, followed by C1, in all age groups .Most symptomatic patients were classified into C2, with a predominance of pain, tiredness, and cramps in this group of patients. In patients with C0 and C6, the most prevalent symptoms were tiredness, heaviness, and burning sensation. Only burning sensation and pain presented statistically significant differences between the genders. Mean number of pregnancies was 2.72 (SD± 2.1). Ninety-one women (8%) had never been pregnant at the time of the study, 408 (36%) had from one to two pregnancies, and 412 women (36.3%) had more than three pregnancies. When comparing number of pregnancies with severity according to CEAP clinical classification, no statistically significant difference was found (p = 0.196). However, the number of women with advanced disease (C4 or greater) was higher in those who had three or more pregnancies (58 vs. 34) .To conclude, 575 (50.6%) patients had some paid work. The mean number of hours working in the sitting and standing positions was 4.92 (SD±2.49) and 6.85 (SD±1.88) hours, respectively, based on an 8-hour work day. When grouping work hours, no differences in severity were found between time working in the sitting and standing positions; although the presence of C5 or C6 ulcer was greater in those who remained in the standing position for more than 4 hours.This article is based on the results from the general consultation to vascular surgeons, which may be a limitation; however, it focused the results on factors associated with venous disease, an aspect useful in daily practice.-6,Although differences between men and women with varicose veins may vary depending on inclusion criteria and methods used in the different studies, most reports show a higher frequency in men than in women, as observed in this series (80% vs. 20%), which may consist of a selection bias, possibly reflecting the greater number of women consulting for varicose veins.3-Several authors have shown disease progression over time,8Vein Consult, in which the prevalence of C0 was 20%.A wide range of symptoms are present in venous disease but are not specific of this entity, which sometimes makes differential diagnosis complex. An analysis of CEAP clinical classification showed that only 1.1% of patients were classified into C0, a stage in which symptoms may be present, but there are no objective signs of varicose veins, a very low percentage when compared with population-based studies such as the The Edinburgh study showed differences in symptoms such as edema, tiredness. and itching, which were more frequent in young women than in men.Pregnancy was found to be a risk factor for the development of varicose veins, maybe due to hemodynamic changes secondary to increased intra-abdominal pressure or to the presence of high circulating levels.-20-Several reports have shown a family history of varicose veins among people affected, with percentages ranging from 42% to 85%, which is consistent with data from the present study, in which 69% of the patients had at least one of padres con afectación.17,There is no consistency in the literature whether smoking plays an important role in the development of varicose veins. In line with the present study, some authors did not observed such relationship;23-31,Obesity has also shown to be related to a positive correlation between BMI and development and severity of varicose vein, with obese patients presenting greater severity, due to increased intra-abdominal pressure resulting from the mass effect of the fat contained within the abdomen compressing the veins of the pelvis and possibly impairing venous return, changes that may be applied to increased intra-abdominal pressure caused by uterine enlargement during pregnancy.28,34-The prevalence of active ulcer in the study population was 2.6%, which is consistent with most series.4-No relationship was found between time working sitting or standing and severity of varicose veins, although the present study did not consider the time of exposure to this factor or whether the position was static or dynamic. Lack of uniformity in these criteria among the different studies made it difficult to find a relationship between occupation and development of varicose veins, in addition to the presence of multiple factors that may have an impact on the development of this condition. However, some reports suggest that remaining in one position for a prolonged time may be positively associated with the development of varicose veins and that positive changes in lifestyle may help reduce the severity of symptoms and improve work-related quality of life.37In conclusion, the results of this study that the distribution of venous disease in the assessed population is very similar to that found in other series, support the progression of clinical severity with age and BMI, and indicate a higher frequency of family history of varicose veins in the evaluated patients. Knowledge of population's characteristics favors guidance on the natural disease history to patients and also improves resource optimization by establishing priorities based on the existence of risk factors or derived complications, which may lead to improved quality of life and reduced health expenditure. Las várices son una condición frecuente en la consulta de atención primaria y una de las más atendidas por los cirujanos vasculares en el mundo, produciendo una variedad de síntomas importantes y complicaciones a largo plazo que van en detrimento de la salud y la calidad de vida, lo cual aumenta igualmente el gasto en saludclinical, etiological, anatomical, pathophysiological (CEAP) y el índice de masa corporal (IMC). Es de anotar que en el 2020 se presentó confinamiento por la pandemia derivada del COVID-19, por lo cual se enlenteció la recolección de los datos, y se tuvieron en cuenta solo las consultas presenciales que se pudieron realizar en este período.Estudio prospectivo y descriptivo en el que se tomaron los datos de pacientes que asistieron a una consulta de cirugía vascular en un centro de enfermedades vasculares en la ciudad de Medellín, Colombia, en el período comprendido entre junio de 2019 y diciembre de 2020. A los pacientes que consultaron por várices, se les indagaba por variables relacionadas con la enfermedad venosa, y las respuestas se descargaron en una base de datos previamente constituida en Excel durante la consulta; en ella se incluyeron variables demográficas, antecedentes patológicos relacionados, sintomatología, tratamientos previos, complicaciones, historia familiar y hábitos y variables clínicas como la severidad según la clasificación Se siguieron los lineamientos en cuanto al manejo de datos personales y políticas de ética de la institución, siendo calificada como investigación sin riesgo. Los datos fueron procesados en SPSS versión 22, utilizando frecuencias y porcentajes para las variables categóricas y medias y desviación estándar (DE) para las variables cuantitativas. Se utilizo la prueba de chi-cuadrado para buscar relación entre las variables categóricas, teniendo en cuenta una p menor 0.05 para significancia estadística.Este estudio se realizó según la Declaración de Helsinki y la ley colombiana para ética e investigación: Resolución 8430 de 1993, expedida por el Ministerio de Salud y Protección Social de Colombia. El protocolo fue aprobado por el comité de ética de la institución realizadora (acta número 002 de 21 de enero del 2019).El total de pacientes evaluados fue de 1.136 pacientes, 911 mujeres (80%) y 225 hombres (20%). La media de la edad fue de 53.51 años  para la población general, 54  años para mujeres, y 51,32  para los hombres, sin diferencia de edad entre los dos grupos . La distribución por género de la edad y otras características pueden verse en la Además, 891  pacientes se encontraron dentro de los grupos del 2 al 6 de la clasificación clínica del CEAP. La enfermedad C4 o mayor fue más frecuente en hombres que en mujeres, mientras que la C2 y C3 fue muy similar en ambos sexos. La distribución de los síntomas fue parecida en hombres y mujeres, encontrando solo diferencias para la presencia de ardor y dolor, que predominaron en las mujeres. El dolor fue el síntoma más referido en ambos géneros, seguido de cansancio y ardor. De los síntomas evaluados, se encontraron diferencias en la percepción por género únicamente para el ardor y el dolor, que predominaron en mujeres .2.Se encontró una baja prevalencia de diabetes, hipotiroidismo, constipación y fumadores en la población estudiada, pero llama la atención la alta prevalencia de sobrepeso y obesidad (64%) en esta población. Sin embargo, no se encontró diferencia al comparar el estado nutricional entre hombres y mujeres, pero sí al compararlo según severidad, siendo mayor la presencia de grados C4 o mayores en los pacientes con IMC por encima de 25 kg/mEl 69% (782 pacientes) tenían antecedente de por lo menos uno de los dos padres con afectación por várices, y el 13,11% (149 pacientes) tenían afectación de ambos padres. Además, 212 pacientes (19%) habían sufrido una o más complicaciones, de estas la úlcera fue la más común, presentándose en 91 pacientes (8%), seguida de la varicorragia 22 . También se observó que 83  pacientes tenían historia de trombosis venosa superficial, 19  tenían historia de trombosis venosa profunda, y 11  tuvieron linfedema asociado. Solo el 2,6% tenían úlcera activa en el momento de la evaluación.No se encontraron diferencias en la distribución de los síntomas por género y grupos de edad, excepto para el cansancio, que predominó en los mayores de 35 años en ambos grupos . En las mujeres se encontraron diferencias en la distribución del peso por grupos de edad, predominando el sobrepeso y la obesidad por encima de los 35 años, mientras que en hombres esta distribución fue similar para todos los grupos de edad .En cuanto a la distribución según el grado de severidad clínica, la mayoría de los pacientes con enfermedad avanzada se encontraron por encima de los 50 años, y la mayoría de los pacientes consultaban en grado C2, seguido por el C1 en todos los grupos de edad .La mayoría de los pacientes sintomáticos se encontraron en la clasificación C2, predominando dolor, cansancio y calambres en este grupo de pacientes. En los pacientes con C0 y C6, los síntomas más prevalentes fueron cansancio, pesadez y ardor. Solo el ardor y el dolor tuvieron diferencias estadísticamente significativas según el género. En la versus 34) . Además, 91 mujeres (8%) no habían tenido ningún embarazo al momento del estudio, 408 (36%) tenían entre uno y dos embarazos, y 412 mujeres  tuvieron más de tres embarazos. Al comparar el número de embarazos y la severidad según CEAP, no se encontró ninguna diferencia estadísticamente significativa , sin embargo, fue mayor el número de mujeres con enfermedad avanzada (C4 o más) en las que tenían 3 o más embarazos (58 rsus 34) .Un total 575  pacientes ejercían algún tipo de labor remunerada. El promedio de horas laboradas sentados, basado en una jornada de 8 horas, fue de 4,92  y de 6,85  para las horas laboradas de pies. Al agrupar las horas laboradas, no se encontraron diferencias entre la severidad de las várices y el tiempo laborado de pies o sentado; sin embargo, la presencia de úlcera C5 o C6 fue mayor en los pacientes que permanecían más de 4 horas de pies.Este artículo se basa en los resultados de la consulta general del cirujano vascular, lo que puede ser una limitación. Sin embargo, centra los resultados en los factores asociados a la enfermedad venosa, algo útil en la práctica diaria.versus 20%), aunque puede ser un sesgo de selección, ya que puede reflejar una mayoría de mujeres que consultan por várices3-versus 15), debido tal vez al impacto cosmético en las mujeres, que aumentaría la consulta en estadios tempranos. Sin embargo, también hay una mayor proporción de síntomas en las mujeres con C1 comparado con los hombres en la misma categoría. Otros estudios han mostrado una mayor proporción de hombres con cambios tróficos visibles y enfermedad avanzada, al igual que en esta serie6,Aunque la diferencia entre hombres y mujeres con várices puede variar según los criterios de inclusión y la metodología entre los diferentes estudios, la mayoría de los reportes muestran una mayor frecuencia en mujeres que hombres, como lo encontrado en esta serie  = 1,82; intervalo de confianza del 95% (IC95%) = 1,433-2,33] en las mujeres que han tenido embarazos comparado con las que noEl embarazo se ha encontrado como factor de riesgo para el desarrollo de várices, puede ser por los cambios hemodinámicos secundarios al aumento de la presión intrabdominal o por la presencia de alto contenido hormonal circulante-20-Diversos reportes han mostrado una historia familiar de várices entre las personas afectadas, con reportes variando entre el 42% y el 85%, lo que concuerda con los datos de este estudio, en el cual el 69% de los pacientes tenían por lo menos uno de los padres con afectación17,No hay consistencia en la literatura acerca de si el tabaquismo juega o no un papel importante en el desarrollo de várices. Al igual que en este estudio, algunos no encuentran esta relación23-versus 2,28%), hallazgos similares a otras series donde un mayor IMC se asocia a desarrollo de úlceras31,La obesidad también se ha señalado con una correlación positiva entre IMC y desarrollo y severidad de las várices, con una mayor severidad en los pacientes obesos, esto debido al aumento de la presión intrabdominal por el efecto de masa de la grasa contenida sobre las venas de la pelvis, lo que puede afectar el retorno venoso, cambios que también pueden aplicarse al aumento de la presión intrabdominal por el crecimiento del útero durante el embarazo28,34-La prevalencia de la úlcera activa en la población estudiada fue del 2,6%, lo cual concuerda con la mayoría de las series4-No se encontró relación entre el tiempo laborado de pies o sentado con la severidad de las várices, pero no se tuvo en cuenta el tiempo de exposición a este factor, o si era una posición estática o dinámica. La falta de uniformidad en estos criterios entre los diferentes estudios ha hecho difícil encontrar una relación entre ocupación y desarrollo de várices, además de la existencia de múltiples factores que pueden influir en su aparición. Sin embargo, algunos reportes sugieren que puede haber una asociación positiva entre las posiciones prolongadas durante mucho tiempo y la aparición de várices, y que el cambio positivo en los estilos de vida puede ayudar a disminuir la severidad de los síntomas y mejorar la calidad de vida en el trabajo37Como conclusión, los resultados de este estudio muestran una distribución de la enfermedad venosa entre la población evaluada muy similar a la encontrada en otras series, apoyan la progresión de la severidad clínica con la edad y el IMC, así como una mayor frecuencia de historia familiar de várices en los pacientes evaluados. El conocimiento de las características de la población favorece la orientación a los pacientes sobre la historia natural de la enfermedad y también mejora la optimización de recursos al establecer prioridades con base en la existencia de factores de riesgo o complicaciones derivadas, lo que puede repercutir en una mejor calidad de vida y una disminución del gasto en salud.


To compare the immediate effects of laser photobiomodulation at wavelengths of 660 nm and 808 nm on fatigue of the orbicularis oris.2 of fluency. An electromyography evaluation was performed before and after the irradiation, concomitantly with the exercise of lip protrusion maintained until the sensation of fatigue. Fatigue was evaluated by a median frequency using the electromyographic fatigue index. The amplitude of the signal was evaluated, examining the root mean square, and the values were normalized by the peak. The difference in amplitude between the upper and lower lips was also analyzed. All variables were compared before and after irradiation.This is a randomized study with 60 women aged between 19 and 43 years. The participants were divided into four groups. Group RG received photobiomodulation with a laser wavelength of 660 nm at four points of the orbicularis oris; group IRG received photobiomodulation with a laser wavelength of 808 nm at the same points; the control group did not receive light treatment; and the placebo group underwent the same procedures as RG and IRG but with the equipment switched off. The irradiation was performed with a laser of 100 mW of power, 4 J of energy per point and 133.3 J/cmNo significant difference was found between the measures taken before and after irradiation.Photobiomodulation with the parameters investigated in this study had no immediate effect on orbicular oris fatigue. Some clinical conditions such as mouth breathing, facial palsy, and deleterious oral habits can impair the orbicularis oris muscle, altering the usual position of the lips-4 and damaging orofacial functions. In some individuals, lip incompetence influences the position of the incisor teeth, causing tooth movement. Therefore, upon detecting lip weakness, it is important to engage in myofunctional therapy with strengthening exercises for the orbicularis oris muscle.The orbicularis oris muscle is actively involved in important functions such as speech, breathing, chewing, swallowing, and facial mimic. The success of the therapy depends on the therapist’s knowledge of the patient’s individual capacities and on the treatment limitations.Myofunctional therapy helps patients to achieve muscle and functional changes through exercises aimed at correcting muscle condition (myotherapy) and some functions,7. This is due to a high concentration of some substrates, such as lactic acid, inside muscle cells, which interferes with intracellular pH and hinders conduction of action potentials essential for muscle activation. It is considered a natural defense mechanism of the muscle and is triggered before damage occurs at the cellular and organ levels. Sustaining muscular exercises can lead to pain, discomfort, and interference with motor performance, causing a decrease in therapy functional time.Muscle fatigue is among these limitations and refers to the inability of the muscle to maintain an expected level of strength over a period of time.Surface electromyography (EMG) is an objective approach that allows to examine muscle fatigue by assessing the number of activated motor units through signal amplitude, in addition to firing frequency of motor neurons through average frequency (AF) analysis. The process of muscle fatigue involves an increase in the number of activated motor units and a decrease in the firing frequency of motor neurons, resulting in a larger amplitude and lower AF, respectively-11. The benefits of photobiomodulation therapy for muscle tissue also include better muscle performance, greater strength gain, and muscle relaxation-14. During the exercise, cells synthetize a great quantity of adenosine triphosphate (ATP) at high speed to supply the energy requirements and prevent fatigue. As it increases ATP input, laser is able to increase muscular exercise functional time, thus delaying fatigue.The literature indicates that photobiomodulation therapy (PBMT) can delay muscle fatigue during maximum and submaximal contractions. One of these studies observed greater resistance to muscle fatigue in the femoral quadriceps of healthy men irradiated with 808-nm-wavelength laser applied during intervals between series of exercises, as well as after the last series.Some studies assessed the effects of photobiomodulation therapy using infrared wavelength laser on muscle performance and found delay/reduction of muscle fatigue found a lower fatigue index in the femoral quadriceps of healthy women who trained for nine consecutive weeks. In this case, a laser with wavelength of 808 nm was applied immediately after each training session. Photobiomodulation therapy with a 808-nm-wavelength laser, before exercise, led to a significantly lower dynamometric fatigue index of the plantar flexor muscles in healthy adults compared to both the control and the placebo group. When applied immediately before the exercise, the same laser decreased muscle fatigue in the rectus femoris muscle of elderly women. However, we found no studies demonstrating the influence of photobiomodulation therapy on lip performance. If the beneficial effect of photobiomodulation on the performance of the orbicularis oris muscle is proven, this therapeutic technique can be used in orofacial myofunctional therapy to optimize the process.Another study.In this context, our objective was to compare the effects of photobiomodulation using laser at the wavelengths of 660 nm (red) and 808 nm (infrared) on the performance of the orbicularis oris muscle in a sustained contraction task. Our hypothesis is that 808-nm-wavelength laser irradiation is more effective for presenting greater depth of penetration into the tissueThis is an experimental, randomized, triple-blind study carried out after approval by the Research Ethics Committee  of Centro Universitário Metodista Izabela Hendrix. All procedures performed in this study are in accordance with the ethical standards of the Research Ethics Committee of the institution, as well as the Helsinki Declaration of 1964 and its amendments. All participating individuals signed an Informed Consent Form. This study is registered on ensaiosclinicos.gov.br (RBR-32RP22).The sample was composed of 60 healthy women with an average age of 25 years – minimum age of 19 years, maximum of 43 years, and standard deviation of 5.9. The participants were randomly distributed into four groups of 15 participants each, as follows:Group 1 (RG): subjected to low-level laser irradiation at a wavelength of 660-nm (red);Group 2 (IRG): subjected to low-level laser irradiation at a wavelength of 808-nm (infrared);Control group (CG): not subjected to low-level laser irradiation.Placebo group (PG): subjected to the same procedure as the RG and IRG without activating the equipment..The sample included women aged between 18 and 60 years. The following exclusion criteria were considered: presence of craniofacial anomaly, disease with neuromuscular involvement, regular use of myorelaxant and/or anti-inflammatory drugs, and contraindications for phototherapy — namely, photosensitivity, pregnancy, glaucoma, undiagnosed lesion on or near the area to be irradiated, infection at the application site, cancer history, use of a pacemaker or another electronic implantGuided by the Frankfurt Plane, each participant was instructed to remain seated on a chair with a 90° angle between the hips, knees and ankles, and with erect posture. The participant’s skin was cleaned using gauze soaked in 70% alcohol at the sites where the electrodes would be placed for the electromyographic evaluation: on the skin above the orbicularis oris muscle, one pair in the upper portion and another in the lower portion. The reference electrode (ground) was positioned on the wrist bone. The electromyographic evaluation was performed concomitantly to the isometric exercise of sustained lip protrusion until the participant felt fatigue, commonly characterized as slight burning, tingling, pain and/or inability to maintain contraction, which the participant was instructed to immediately signal to the researcher.We recorded the muscle electrical signal using a Miotec® equipment, New Miotool Face model, with two input channels, 16-bit resolution, 3000 V safety isolation, maximum acquisition capacity of 3,000 samples per second, 20 Hz high-pass, and 500 Hz low-pass filters. The Miotec Suite software was used to collect and analyze the data on a laptop computer that was not connected to the mains. For data collection, we used circular, double-sided surface sensors made of Ag/AgCl material with Miotec® fixed conductive gel. The electrodes had a diameter of 10 mm and the distance between each other was fixed at 20 mm. Equipment gain was automatic. Input impedance was 10 GΩ and the common mode rejection ratio was >100 dB.. From the beginning of the activity, we disregarded the 0.5 initial seconds to homogenize the analyzed sections. The signal was divided into sections of 5 s, which were analyzed in the AF domain (through fast Fourier transform): first 5 seconds (F5), last 5 seconds (L5), and last section of 5 seconds with duration common to both signals (C5). As the electric signal of the lips was obtained before and after the PBMT, with different durations, this last parameter was required to ensure that the comparison of signals before and after the laser application was performed after the same muscle contraction time, as illustrated in To analyze the signal, we discarded the first seconds before the beginning of muscle activity, considered as the moment when the electric signal amplitude exceeded the average increased by two standard deviations of the signal obtained at restWe also analyzed the values of electric signal amplitude in RMS and normalized by the signal peak by comparing with the pre- and post-laser stages. The difference in signal amplitude between the upper and lower lips was obtained to examine a possible alteration in muscle balance. Finally, we calculated the electromyographic fatigue index (EFI) by dividing the values of final FM by initial FM.,16; (b) EFI calculated using the formula EFI=C5/F5; (c) values of RMS amplitude in the signal, in µV; (d) amplitude normalized by the peak, and (e) difference in electric signal amplitude between the upper and lower lips.We compared the following variables regarding the moments before and after PBMT: (a) EFI calculated using the formula EFI=L5/F5After the initial electromyographic evaluation, we performed a low-level laser irradiation using a MMOptics® equipment . We applied the laser on four points of the orbicularis oris muscle: two points on the upper lip and two points on the lower lip  at a dosIn all groups, irradiation was performed by placing the tip of the equipment against the skin of the participant. The device was sanitized with 70% alcohol before each application and the tip was covered with a transparent plastic film, which was changed with each new participant. During the irradiation procedure, both researchers and participants used goggles supplied by the equipment manufacturer.The researcher who applied the laser was not the same who carried out the electromyographic evaluation; the latter was blind to the group to which the individual belonged. The participants were also not aware of which group they were part of. The electric signals were analyzed by a third researcher, who was also blind to the group each participant belonged to and was not informed if the signal analyzed referred to a collection before or after irradiation.Following irradiation, the participants were given a five-minute rest period, after which the electromyographic evaluation procedures were repeated.We used the Kolmogorov-Smirnov statistical test to assess the distribution of the variables in the study. Since the variables did not present normal distribution, the analyses were performed through non-parametric tests. The Kruskal-Wallis test was applied to compare the dosages among the groups, while the Wilcoxon test compared the variables before and after the laser intervention. All tests were performed at a significance level of 5%.The results indicated no statistically relevant difference by comparing the groups regarding age .Comparative analysis of the electromyographic fatigue indices before and after PBMT indicated no statistically significant difference for the upper and lower lips in any of the groups .The average values of RMS and normalized by the peak amplitudes did not indicate any statistically significant difference compared before and after the PBMT .Additionally, no statistically relevant differences were found in the comparison analysis between the upper and lower lips before and after the PBMT .Our study did not find any immediate effects of PBMT on electromyographic fatigue of the orbicularis oris muscle. So far, studies assessing the effects of photobiomodulation on this musculature were not found.,20. Therefore, we decided to include only female participants in the sample. The statistical analysis demonstrated that the tested groups were homogeneous regarding age, which is relevant since lip strength is also influenced by age. Our choice for the dose of 4 J was based on previous studies addressing the effects of PBMT on the performance of different muscles,22.The variable gender of the participants could have influenced the remaining variables, as men usually have greater lip strength than women studied the effects of red (660 nm) and infrared (830 nm) lasers on the performance of the biceps brachii muscle and found that both lengths had positive effects. However, only infrared laser influenced fatigue. According to the authors, such difference results from an increased penetration range of the infrared laser, which is able to reach deeper fibers, while red wavelength laser acts more superficially. Since light penetration increases as the wavelength laser increases, infrared laser is more widely used in studies addressing muscle performance analysis. However, as the orbicularis oris is a superficially located fine muscle, we considered important to observe not only the effects of the infrared but also of the red laser on this muscle.de Almeida et al.,26. da Silva Alves et al. did not observe any effect of infrared laser (850 nm) on the electromyographic signal amplitude of the quadriceps and gastrocnemius muscles in young men, while dos Santos Maciel et al. found no influence of 780-nm laser irradiation before strength and resistance exercises on the RMS of anterior tibial muscles, measured during the exercises. However, Muñoz et al. observed an increase in electromyographic signal amplitude after infrared laser (780 nm) irradiation on the masseter muscle of healthy men at a dose of 0.8 J per point at 8 irradiated points. The differences in the dosimetry parameters and muscles assessed did not enable comparison of these studies’ results.PBMT at both wavelengths was not able to influence the parameters related to electromyographic signal amplitude , thus corroborating some previous studies. Such interaction alters the redox potential of the cytoplasm and accelerates the flow in the mitochondrial electron transport chain, increasing ATP synthesis, which explains the improved muscle performance after PBMT found in some studies,28,29. A possible explanation for our results concerns the short time period between laser application and data collection, which is insufficient for the light to interact with the tissue. The existence of a dose-response curve reported in the irradiation parameters could be another explanation. The laser energy applied to the mouth orbicular may have been insufficient to improve muscle performance.PBMT has demonstrated positive results when interacting with biological tissues, promoting an increase in the production of cellular energy, especially due to the absorption of light energy by mitochondria, thus stimulating the respiratory chain,30 and contradicting others,11,16. After subjecting the biceps brachii muscle of young women to a 808-nm- wavelength laser irradiation before the fatigue protocol, Higashi et al. did not observe any effect of the laser on electromyographic fatigue. Similarly, Toma et al. demonstrated that applying PBMT using 808-nm laser after strengthening exercises for the quadriceps of elderly individuals did not alter the electromyographic fatigue index. However, another study found that PBMT (808 nm) carried out immediately before exercises for the rectus femoris muscle significantly reduced the electromyographic fatigue index. After subjecting the femoral quadriceps muscle to a 808-nm laser irradiation between and after exercises for two days, de Brito Vieira et al. verified a decrease in electromyographic fatigue for the vastus medialis and rectus femoris in relation to the placebo group, suggesting an influence of post-irradiation time on reduced muscle fatigue.In this study, regardless of the wavelength, PBMT did not have any effect on electromyographic fatigue, corroborating some studies applied an isokinetic dynamometry and found that the PBMT (808 nm) before the exercise reduced fatigue in the ankle plantar flexors of healthy individuals, but did not alter the average frequency of the surface electromyography. The authors suggest that the energy source of the primary action can be related to energy production inside the muscle fibers rather than to the influence of neuromuscular recruitment. The evolution of fatigue encompasses several factors, such as alteration in motor unit recruitment, decrease in electric potential of the membrane, and increase in levels of reactive oxygen species and reactive nitrogen species. Although average frequency is regarded as a satisfactory parameter for the electromyographic analysis of neuromuscular fatigue, it reflects the firing rate of neuromuscular action potential. The lack of difference in the average frequency found in this study can be related to the absence of PBMT influence on the neuromuscular recruitment pattern.de Souza et al.Our study also assessed the difference in signal amplitude between the lower and upper lips for considering that it influences the balance between the muscles after PBMT; however, such effect could not be proven. No studies were found to address this variable for comparison.The limitations of this study include short rest time between exercises, as well as between irradiation and exercise, and lack of control of anatomical characteristics, such as lip thickness, which is likely to influence the results. For this reason, our comparisons were exclusively intragroup. We suggest that further studies use different doses and include individuals with orofacial myofunctional alterations, such as mouth breathers.We found no differences in the surface electromyography between the measures of average frequency and signal amplitude performed before and after mouth orbicular irradiation with low-level laser using the wavelengths of 660 nm and 830 nm. Therefore, photobiomodulation based on the parameters assessed in this study did not result in immediate effects on the fatigue of mouth orbicular. . Algumas condições clínicas, tais como respiração oral, paralisia facial e hábitos orais deletérios, podem enfraquecer o músculo orbicular da boca, causando alteração na postura habitual dos lábios-4 e prejuízo para as funções orofaciais. Em alguns indivíduos, a incompetência labial influencia a posição dos dentes incisivos, gerando movimentação dentária. Sendo assim, quando a fraqueza labial é detectada, exercícios para fortalecimento do músculo orbicular da boca por meio da terapia miofuncional fazem-se necessários.O músculo orbicular da boca está envolvido ativamente em importantes funções como fala, respiração, mastigação, deglutição e mímica facial. O sucesso da terapia depende do conhecimento do terapeuta em relação às capacidades individuais e limitações do tratamento.A terapia miofuncional auxilia o paciente a alcançar mudanças musculares e funcionais, por meio de exercícios para modificação da condição muscular (mioterapia) e do trabalho direcionado para as funções que precisam ser corrigidas,7. Isso ocorre devido à alta concentração de alguns substratos no interior das células musculares, tais como ácido lático, que interfere no pH intracelular, dificultando a condução dos potenciais de ação essenciais para a ativação muscular. É considerada um mecanismo de defesa natural do músculo, acionado antes que ocorram danos a níveis celulares e orgânicos. A sustentação de exercícios musculares pode acarretar dores, desconforto e interferência no desempenho motor, causando uma diminuição no tempo funcional da terapia.Uma dessas limitações, a fadiga muscular, refere-se à inabilidade do músculo para manter um nível de força esperado durante um determinado período de tempo.Um método objetivo que possibilita a investigação da fadiga muscular é a eletromiografia de superfície (EMG). A EMG permite avaliar o número de unidades motoras ativadas, por meio da amplitude do sinal, e a frequência de disparo dos neurônios motores, pela análise da frequência mediana (FM). No processo de fadiga muscular, ocorre o aumento do número de unidades motoras ativadas e diminuição da frequência de disparo dos neurônios motores, resultando em uma maior amplitude e menor FM, respectivamente-11. Os benefícios da terapia por fotobiomodulação para o tecido muscular incluem, ainda, melhor desempenho muscular, maior ganho de força e relaxamento da musculatura-14. Durante o exercício, as células sintetizam grande quantidade de adenosina trifosfato (ATP), em velocidade acelerada, para suprir as necessidades energéticas e evitar a fadiga. O laser aumenta o aporte de ATP, por isso é capaz de aumentar o tempo funcional do exercício muscular, retardando assim a fadiga.A literatura indica que a terapia por fotobiomodulação (TFBM) pode retardar a fadiga muscular durante contração máxima e submáxima. Um estudo encontrou aumento da resistência à fadiga muscular do quadríceps femoral de homens saudáveis quando irradiados com laser com comprimento de onda de 808 nm, aplicado durante intervalos entre séries de exercícios e após a última série. Outro estudo verificou diminuição no índice de fadiga do quadríceps femoral de mulheres saudáveis que treinaram por nove semanas consecutivas. Nesse caso, um laser de comprimento de onda de 808 nm foi aplicado imediatamente após cada sessão de treinamento. A terapia por fotobiomodulação, com laser com comprimento de onda de 808 nm, antes do exercício, provocou diminuição significativa do índice de fadiga dinamométrica dos músculos flexores plantares em adultos saudáveis quando comparados aos grupos controle e placebo. O mesmo laser, aplicado imediatamente antes do exercício, reduziu a fadiga muscular do músculo reto femoral em mulheres idosas. No entanto, não foram encontrados estudos que comprovassem a influência da terapia por fotobiomodulação no desempenho dos lábios. Se comprovado o efeito benéfico da fotobiomodulação no desempenho do músculo orbicular da boca, esta modalidade terapêutica poderá ser utilizada na terapia miofuncional orofacial, para otimizar o processo terapêutico.Alguns estudos avaliaram os efeitos da terapia por fotobiomodulação, usando laser com comprimento de onda infravermelho, no desempenho muscular e verificaram retardo/diminuição da fadiga muscular.Diante disso, o objetivo do presente estudo foi comparar os efeitos da fotobiomodulação com laser nos comprimentos de onda de 660 nm (vermelho) e 808 nm (infravermelho) no desempenho do músculo orbicular da boca em tarefa de contração sustentada. A hipótese levantada foi que a irradiação com laser com comprimento de onda de 808 nm seria mais efetiva, visto que apresenta maior profundidade de penetração no tecidoTrata-se de um estudo experimental, randomizado, triplo-cego, realizado após a aprovação do Comitê de Ética em Pesquisa (sob o número CAAE 03142818.9.0000.5096) do Centro Universitário Metodista Izabela Hendrix. Todos os procedimentos realizados nesta pesquisa estão de acordo com padrões éticos do Comitê de Ética em Pesquisa da instituição e com a Declaração de Helsinki de 1964 e suas emendas. Todos os indivíduos envolvidos assinaram o Termo de Consentimento Livre e Esclarecido. O estudo foi registrado em ensaiosclinicos.gov.br (RBR-32RP22).A amostra foi composta por 60 mulheres saudáveis, com média de idade de 25 anos, idade mínima de 19 anos, máxima de 43 anos e desvio-padrão de 5,9. As participantes foram alocadas de forma randomizada em quatro grupos, com 15 participantes cada, da seguinte forma:laser de baixa intensidade e comprimento de onda de 660 nm (vermelho);Grupo 1 (GV): foi submetido à irradiação com laser de baixa intensidade e comprimento de onda de 808 nm; (infravermelho);Grupo 2 (GIV): foi submetido à irradiação com laser de baixa intensidade;Grupo Controle (GC): não foi submetido à irradiação com Grupo Placebo (GP): foi submetido ao mesmo procedimento do GV e GIV, porém, o equipamento não foi acionado..Foram incluídas na amostra, mulheres com idade entre 18 e 60 anos. Constituíram os critérios de exclusão: possuir anomalia craniofacial, doença com comprometimento neuromuscular, uso regular de medicamentos miorrelaxantes e/ou anti-inflamatórios, apresentar contraindicações para a fototerapia, sendo elas fotossensibilidade, gravidez, glaucoma, lesão sem diagnóstico sobre a área a ser irradiada ou próxima a ela, infecção no local da aplicação, histórico de câncer, uso de marcapasso ou outro implante eletrônicoCada participante foi instruída a permanecer sentada em uma cadeira, com ângulo de 90° entre quadril, joelhos e tornozelos, postura ereta, guiada pelo Plano de Frankfurt. Foi realizada a limpeza da pele da participante, utilizando gaze embebida em álcool 70% nos locais em que seriam colocados os eletrodos para a avaliação eletromiográfica: sobre a pele acima do músculo orbicular da boca, sendo um par na porção superior e outro par na porção inferior. O eletrodo referência (terra) foi posicionado no osso do punho. A avaliação eletromiográfica foi realizada concomitantemente ao exercício isométrico de protrusão labial sustentada até a participante ter a sensação de fadiga, comumente caracterizada como ligeiro ardor, formigamento, dor e/ou incapacidade de manter a contração, sendo que a participante foi orientada a sinalizar imediatamente este momento ao pesquisador.O registro do sinal elétrico muscular foi realizado utilizando o equipamento da marca Miotec®, modelo New Miotool Face, com dois canais de entrada, resolução de 16 bits, isolamento de segurança de 3000 V, capacidade de aquisição máxima de 3000 amostras por segundo, filtros passa alta de 20 Hz e passa baixa de 500 Hz. O software Miotec Suite foi utilizado para coleta e análise dos dados em um notebook que não estava conectado à rede elétrica. Para captação dos dados foram utilizados sensores superficiais circulares, do tipo double, de material Ag/AgCl, com gel condutor fixo, sendo a marca Miotec®. Os eletrodos apresentavam diâmetro de 10 mm e a distância entre os eletrodos era fixa de 20 mm. O ganho do equipamento era automático. A impedância de entrada era de 10 GΩ e a taxa de rejeição de modo comum >100 dB.. A partir do início da atividade, foram desconsiderados os 0,5 s iniciais a fim de homogeneizar os trechos analisados. O sinal foi dividido em trechos de 5 s, sendo analisados, no domínio da FM (por transformada rápida de Fourier): os primeiros 5 segundos (F5), os últimos 5 segundos (L5) e o último trecho de 5 segundos com duração comum aos dois sinais (C5). Uma vez que, o sinal elétrico dos lábios foi obtido antes e após a TFBM, tendo diferentes durações, este último parâmetro foi necessário para garantir que a comparação de sinais antes e após a aplicação do laser fosse realizada após o mesmo tempo de contração muscular, como ilustrado na Para análise do sinal, os primeiros segundos anteriores ao início da atividade muscular foram excluídos, considerando-se como início da atividade muscular o momento em que a amplitude do sinal elétrico ultrapassou a média acrescida de dois desvios padrão do sinal obtido em repousolaser. A diferença de amplitude do sinal entre os lábios superior e inferior foi obtida para a investigação de uma possível mudança no equilíbrio muscular. Por fim, calculou-se o índice de fadiga eletromiográfica (IFE), por meio da divisão entre os valores da FM final pela inicial.Também foram analisados os valores de amplitude do sinal elétrico em RMS e normalizados pelo pico do sinal, comparando-se os momentos pré e pós ,16; (b) o IFE calculado usando a fórmula IFE=C5/F5; (c) os valores de amplitude RMS do sinal, em µV; (d) a amplitude normalizada pelo pico; e (e) a diferença da amplitude do sinal elétrico entre lábios superior e inferior.As seguintes variáveis foram comparadas entre os momentos anterior e posterior à TFBM: (a) o IFE calculado usando a fórmula IFE=L5/F5laser de baixa intensidade, utilizando equipamento da marca MMOptics® . Os parâmetros de irradiação utilizados estão descritos no laser foi calibrado pelo fabricante.Após a avaliação eletromiográfica inicial, foi realizada a irradiação com laser foi aplicado em quatro pontos no músculo orbicular da boca: dois pontos no lábio superior e dois pontos no lábio inferior  e infravermelho (830 nm) no desempenho do músculo bíceps braquial e verificaram que ambos os comprimentos exerceram efeitos positivos. Contudo, somente o laser infravermelho influenciou a fadiga. De acordo com os autores, essa diferença resulta do maior alcance de penetração do laser infravermelho, que é capaz de atingir fibras musculares mais profundas, enquanto o laser com comprimento de onda vermelho atua mais superficialmente. A penetração da luz aumenta, de acordo com o aumento do comprimento de onda do laser. Por essa razão, o laser infravermelho é mais empregado em estudos de análise de desempenho muscular. No entanto, como o músculo orbicular da boca é fino e superficialmente localizado, considerou-se importante verificar os efeitos do laser vermelho, além do infravermelho, neste músculo.de Almeida et al.,26. da Silva Alves et al. não detectaram efeito do laser infravermelho (850 nm) sobre a amplitude do sinal eletromiográfico dos músculos quadríceps e gastrocnêmio de homens jovens e dos Santos Maciel et al. também não encontraram influência da irradiação com laser de 780 nm antes dos exercícios de força e resistência no RMS dos músculos tibiais anteriores, medidos durante os exercícios. Muñoz et al., contudo, observaram aumento na amplitude do sinal eletromiográfico após a irradiação com laser infravermelho (780 nm) no músculo masseter em homens saudáveis, usando uma dose de 0,8 J por ponto em 8 pontos irradiados. As diferenças nos parâmetros dosimétricos e músculos avaliados impossibilitam a comparação dos resultados entre as pesquisas.A TFBM, com ambos os comprimentos de onda, não exerceu efeito nos parâmetros relacionados à amplitude do sinal eletromiográfico , o que concorda com alguns estudos. Essa interação altera o potencial de redox do citoplasma e acelera o fluxo na cadeia de transporte de elétrons mitocondrial, aumentando a síntese de ATP, o que explica o melhor desempenho muscular verificado por alguns estudos após a TFBM,28,29. Uma possível explicação para os nossos resultados, inclui o curto período de tempo entre a aplicação do laser e a coleta dos dados, sendo insuficiente para a luz interagir com o tecido. Outra explicação pode ser a existência de uma curva dose-resposta relatada nos parâmetros de irradiação. A energia do laser aplicada no orbicular da boca pode não ter sido suficiente para melhorar a performance muscular.A TFBM tem demonstrado resultados positivos na interação com tecidos biológicos, promovendo o aumento na produção de energia celular, devido principalmente à absorção de energia luminosa pelas mitocôndrias, estimulando, assim, a cadeia respiratória,30 e contrário a outros,11,16. Higashi et al. irradiaram o músculo bíceps braquial de mulheres jovens com laser de comprimento de onda de 808 nm antes do protocolo de fadiga e não verificaram efeito do laser na fadiga eletromiográfica, bem como Toma et al. mostraram que TFBM com laser de 808 nm, aplicada após exercícios de força para quadríceps em pessoas idosas, não modificou o índice de fadiga eletromiográfica. Contudo, outro estudo verificou que a TFBM (808 nm), realizada imediatamente antes de exercícios para o músculo reto femoral, reduziu significativamente o índice de fadiga eletromiográfica. de Brito Vieira et al. irradiaram o músculo quadríceps femoral entre e após os exercícios com laser de 808 nm, e, após dois dias da irradiação, os autores verificaram diminuição na fadiga eletromiográfica para o vasto medial e reto femoral comparado ao grupo placebo, o que sugere que há influência do tempo pós irradiação na diminuição da fadiga muscular.No presente estudo a TFBM, independentemente do comprimento de onda, também não exerceu efeito na fadiga eletromiográfica. Esse achado está em consonância com o de alguns estudos verificaram, por meio de dinamometria isocinética, que a TFBM (808 nm) antes do exercício reduziu a fadiga nos flexores plantares do tornozelo de indivíduos saudáveis, mas não alterou a frequência mediana da eletromiografia de superfície. Os autores sugerem que a fonte de ação primária de energia pode estar relacionada à produção de energia dentro das fibras musculares, ao invés da influência do recrutamento neuromuscular. O desenvolvimento da fadiga envolve vários fatores como mudança no recrutamento da unidade motora, diminuição do potencial elétrico de membrana e aumento dos níveis de espécies reativas de oxigênio e de espécies reativas de nitrogênio. A frequência mediana é considerada um bom parâmetro para análise eletromiográfica da fadiga neuromuscular. Contudo, ela reflete a taxa de disparo dos potenciais de ação neuromusculares. A falta de diferença na frequência mediana verificada nesse estudo pode estar relacionada à falta de influência da TFBM no padrão de recrutamento neuromuscular.de Souza et al.Avaliou-se ainda, neste estudo, a diferença na amplitude do sinal entre o lábio inferior e superior, pois se pensou que poderia haver um efeito no equilíbrio entre os músculos após a TFBM, mas esse efeito não foi provado. Não foram encontrados estudos que tenham estudado esta variável para comparação.Constituíram limitações do estudo o curto tempo de descanso entre os exercícios, e entre a irradiação e o exercício e a falta de controle das características anatômicas, como a espessura dos lábios, que poderiam possivelmente influenciar os resultados. Por esse motivo, as comparações foram feitas apenas intragrupo. Sugerem-se mais pesquisas com diferentes doses e que incluam indivíduos com alterações miofuncionais orofaciais, tais como respiradores orais.laser de baixa intensidade nos comprimentos de onda 660 nm e 830 nm. Portanto, a fotobiomodulação com os parâmetros avaliados na presente pesquisa não resultou em efeitos imediatos sobre a fadiga no orbicular da boca.Não foram encontradas diferenças na eletromiografia de superfície entre as medidas de frequência mediana e amplitude do sinal, realizadas antes e depois da irradiação do orbicular da boca com