Intrinsic foot strengthening and electrostimulation in older adults - Randomized clinical trial / Fortalecimento intrínseco do pé e eletroestimulação em idosos - Ensaio clínico randomizado

Abstract Introduction Aging reduces functional capacity related to reduced toe plantar flexion strength. The exercise for strengthening the foot's intrinsic muscles can be optimized using electrostimulation. Due to the scarcity of data in the literature on these methods, further studies are necessary. Objective To evaluate and compare the effects of training to strengthen the foot's intrinsic muscles on the risk of falls in older adults. Methods This is a randomized clinical trial with 19 older patients allocated into three groups: control (CG; n = 7), exercise (EG; n = 6), and exercise+electrostimulation (EEG; n = 6). The EG received an exercise protocol for the foot's intrinsic muscles, the EEG received the same protocol with Neuromuscular electrical stimulation (NMES), and the CG received guidance regarding preventing falls. The individuals were evaluated before and after the intervention using the Single-Limb balance test (SLBT), Functional Reach Test (FRT), Timed Up and Go (TUG), and Paper Grip Test (PGT) tests. One and two-way ANOVA was used for the statistical analysis. Statistical significance was set at p < 0.05. Results There was a significant improvement in the TUG test (9.64 ± 1.78 vs. 8.20 ± 1.94) in relation to the EG. With the EEG, there was an improvement both in the TUG (12.68 ± 4.01 vs. 10.61 ± 3.70) and in the FRT (26.37 ± 7.66 vs. 33.14±9.73) with p < 0.05). Conclusion An exercise protocol associated with electrostimulation improves performance in func-tional and dynamic balance tests in older adults.

Resumo Introdução O envelhecimento reduz a capacidade fun-cional, que está relacionada com a redução de força muscular de flexão plantar dos dedos dos pés. O exercício de fortalecimento da musculatura intrínseca do pé pode ser otimizado com o uso da eletroestimulação eletro (EENM). Devido à escassez de dados na literatura sobre a utilização desses métodos, torna-se necessário realizar novos estudos. Objetivo Avaliar e comparar os efeitos do treino de fortalecimento da musculatura intrínseca do pé no risco de queda em idosos. Métodos Trata-se de um ensaio clínico randomizado, no qual 19 idosos foram alocados em três grupos: controle (GC; n = 7), exercício (GE; n = 6) e exercício+eletroestimulação (GEE; n = 6). O GE recebeu um protocolo de exercícios para a musculatura intrínseca do pé, o GEE recebeu o mesmo protocolo seguido de EENM e o GC recebeu orientações quanto à prevenção de quedas. Os indivíduos foram avaliados antes e após a intervenção através dos testes de Apoio Unipodal , Teste de Alcance Funcional (TAF), Timed Up and Go (TUG) e Paper Grip Test (PGT). Para a análise estatística, utilizou-se ANOVA 1 e 2 vias. Considerou-se estatisticamente significante um valor de p < 0,05. Resultados Observou-se melhora significativa no teste TUG (9,64 ± 1,78 vs 8,20 ± 1,94) em relação ao GE. Em relação ao GEE, houve melhora tanto no TUG (12,68 ± 4,01 vs 10,61 ± 3,70) quanto no TAF (26,37 ± 7,66 vs 33,14 ± 9,73). Conclusão Conclui-se que um protocolo de exercício associado à eletroestimulação melhora o desempenho nos testes de equilíbrio funcional e equilíbrio dinâmico em indivíduos idosos.

Fototerapia melhora a capacidade muscular em idosos: estudo clínico randomizado cruzado duplo-cego / Phototherapy improves muscle capacity in the elderly: a randomized double-blind crossover clinical study

Avaliou-se os efeitos agudos da fototerapia na capacidade muscular de idosos. Ensaio clínico randomizado cruzado duplo-cego. Sete idosos foram randomizados em dois grupos: grupo fototerapia (GF) e grupo placebo (GP). O primeiro grupo recebeu fototerapia em seis pontos dos músculos do quadríceps femoral bilateralmente na primeira sessão e placebo na segunda, enquanto o segundo grupo foi submetido ao oposto. Os indivíduos foram avaliados quanto à força muscular, teste sentar-levantar da cadeira (TSLC) e teste de caminhada de 2 minutos (TC2´). Para análise estatística foi utilizado ANOVA de 2 vias com medidas repetidas com post-hoc de Student-Newman-Keuls e nível de significância de 5%. Houve aumento no desempenho no TSLC (GF: 8,50 ± 5,94% vs. GP: -2,44 ± 7,13%; p = 0.0121) e no TC2´ (GF: 7,12 ± 3,31% vs. GP: -1,41 ± 4,68%; p = 0,0021). Não foi observado ganho de força muscular através do teste de força muscular com esfigmomanômetro modificado (GF: 0,67 ± 2,65% vs. GP: 2,06 ± 6,29%; p = 1,00). Esses achados indicam que a fototerapia é capaz de melhorar a capacidade muscular na população idosa.

Efeitos do treinamento resistido nos músculos escapulares nas epicondilalgias: revisão sistemática e metanálise / Effects of resistant training on scapular muscles in epicondylalgia: systematic review and meta-analysis

As epicondilalgias medial e lateral são as causas mais frequentes de sintomas dolorosos nos membros superiores. Observa-se um aumento no número de publicações sobre os efeitos do treino da musculatura escapular no manejo clínico das epicondilalgias, porém desconhecemos uma revisão sistemática que avalie os efeitos do treinamento resistido nos músculos escapulares nessa condição. Objetivo: revisar sistematicamente os efeitos do treinamento resistido nos músculos escapulares nas epicondilalgias. Metodologia: foi realizada uma busca científica (SciELO, PubMed, LILASCS, PEDro) de estudos clínicos controlados sobre os efeitos do treinamento resistido nos músculos escapulares nas epicondilalgias publicados até maio 2021. A escala de PEDro foi aplicada para avaliação da qualidade metodológica. Resultados: foram encontrados 266 artigos e 3 foram incluídos na revisão sistemática. Os estudos inclusos enfatizaram o treinamento dos músculos trapézio médio, trapézio inferior e serrátil anterior associados a reabilitação convencional. Através da análise individual dos estudos observa-se efeitos positivos do treino escapular na dor, na função (Patient Rated Tennis Elbow Evaluation Questionnaire ­ PRTEE) e na força de preensão manual em indivíduos com epicondilalgias lateral. A metanálise revela que adicionar exercícios escapulares a fisioterapia convencional reduz a dor (EVA 0-10) em 1.23 (95% IC, 2,00-0,47, p=0,002, I2=47%, p para heterogeidade = 0.17) e aumenta a função (PRTEE 0-100) em 5.47 (95% IC, 10,00-0,93, p=0,02, I2=0%, p para heterogeidade = 0.84) na epicondilalgias lateral. A média de pontuação da escala PEDro foi de 6,33/10. Conclusão: o treinamento resistido dos músculos escapulares associados a reabilitação reduzem dor e aumentam função em indivíduos com epicondilalgia lateral. Sugere-se a realização de mais estudos com melhor qualidade metodológica para avaliar a importância do fortalecimento dos músculos escapulares em indivíduos com epicondilalgias. (AU)

Medial and lateral epicondylalgia are the most requente causes of painful symptoms in the upper limbs. There is na increase in the number of publications on the effects of scapular muscle training in the clinical management of epicondylalgia, but we do not know of a systematic review that assesses the effects of resistance training on scapular muscles in this condition. The aim of the study was to systematically review the effects of resistance training on scapular muscles in epicondylalgia. A scientific search (SciELO, PubMed, LILASCS, PEDro) of controlled clinical studies on the effects of resistance training for the scapular muscles in epicondylagias published until May 2021 was performed. The PEDro scale was applied to assess the methodological quality. 266 articles were found and 3 were included in the systematic review. The included studies emphasized the training of the middle trapezius, lower trapezius and serratus anterior muscles associated with conventional rehabilitation. Through the individual analysis of the studies, positive effects of scapula training on pain, function Patient Rated Tennis Elbow Evaluation Questionnaire ­ PRTEE) and handgrip strength were observed in individuals with lateral epicondylalgia. The meta-analysis reveals that adding scapular exercises to conventional physical therapy reduces pain (VAS 0-10) by 1.23 (95% CI, 2.00-0.47, p=0.002, I2=47%, p for heterogeneity = 0.17) and increases function (PRETEE 0-100) by 5.47 (95% CI, 10.00- 0.93, p=0.02 I2=0%, p for heterogeneity = 0.84) in lateral epicondylalgia. The average score of the studies on the PEDro scal e was 6.33 out 10. In conclusion, resistance training of scapular muscles associated with rehabilitation reduces pain the increases function in individuals with lateral apicondylalgia. It is suggested that more studies be carried out with better methodological quality to assess the importance of strengthening the scapular muscles in individuals with epicondylalgia. (AU)

Neuromuscular electrical stimulation but not photobiomodulation therapy improves cardiovascular parameters of rats with heart failure.

The aim of the present study was to analyze the effect of neuromuscular electrical stimulation (NMES) and photobiomodulation (PBMT) on the cardiovascular parameters, hemodynamic function, arterial baroreflex sensitivity (BRS), and autonomic balance (ANS) of rats with heart failure (HF). Male Wistar rats (220-290 g) were organized into five groups: Sham (n = 6), Control-HF (n = 5), NMES-HF (n = 6), PBMT-HF (n = 6), and NMES + PBMT-HF (n = 6). Myocardial infarction (MI) was induced by left coronary artery ligation. Animals were subjected to an eight-week NMES and PBMT protocol. Statistical analysis included the General Linear Model (GLM) followed by a Bonferroni post-hoc test. Rats of the NMES-HF group showed a higher MI area than the Control-HF (P = 0.003), PBMT-HF (P = 0.002), and NMES + PBMT-HF (P = 0.012) groups. NMES-HF and NMES + PBMT-HF showed higher pulmonary congestion (P = 0.004 and P = 0.02) and lower systolic pressure (P = 0.019 and P = 0.002) than the Sham group. NMES + PBMT-HF showed lower mean arterial pressure (P = 0.02) than the Sham group. Control-HF showed a higher heart rate than the NMES-HF and NMES + PBMT-HF (P = 0.017 and P = 0.013) groups. There was no difference in the BRS and ANS variables between groups. In conclusion, eight-week NMES isolated or associated with PBMT protocol reduced basal heart rate, systolic and mean arterial pressure, without influence on baroreflex sensibility and autonomic control, and no effect of PBMT was seen in rats with HF.

Quantification of DNA Damage in Different Tissues in Rats with Heart Failure.

BACKGROUND: Chronic heart failure (CHF) is a complex syndrome which comprises structural and functional alterations in the heart in maintaining the adequate blood demand to all tissues. Few investigations sought to evaluate oxidative DNA damage in CHF. OBJECTIVE: To quantify the DNA damage using the comet assay in left ventricle (LV), lungs, diaphragm, gastrocnemius and soleus in rats with CHF. METHODS: Twelve male Wistar rats (300 to 330 g) were selected for the study: Sham (n = 6) and CHF (n = 6). The animals underwent myocardial infarction by the ligation of the left coronary artery. After six weeks, the animals were euthanized. It was performed a cell suspension of the tissues. The comet assay was performed to evaluate single and double strand breaks in DNA. Significance level (p) considered < 0.05. RESULTS: The CHF group showed higher values of left ventricle end-diastolic pressure (LVEDP), pulmonary congestion, cardiac hypertrophy and lower values of maximal positive and negative derivatives of LV pressure, LV systolic pressure (p < 0.05). CHF group showed higher DNA damage (% tail DNA, tail moment and Olive tail moment) compared to Sham (p < 0.001). The tissue with the highest damage was the soleus, compared to LV and gastrocnemius in CHF group (p < 0.05). CONCLUSION: Our results indicates that the CHF affects all tissues, both centrally and peripherically, being more affected in skeletal muscle (soleus) and is positively correlated with LV dysfunction.

Teste de AVD-Glittre em idosas eutróficas, com sobrepeso e obesidade / Glittre ADL test in eutrophic, overweight and obese elderly

O teste de AVD-Glittre (TGlittre) foi elaborado e validado para mensuração da capacidade funcional durante realização de atividades de vida diária, em pacientes com doença pulmonar obstrutiva crônica (DPOC), porém vem sendo utilizado em diversas outras populações. O objetivo do estudo foi averiguar a aplicabilidade através do TGlittre em uma amostra de indivíduos idosos eutróficos, com sobrepeso e obesidade. Trata-se de um estudo experimental e transversal, no qual foram avaliadas 21 idosas, alocadas por IMC, nos grupos eutrófico (n = 8), sobrepeso (n = 6) e obeso (n = 7). Foram avaliados entre os grupos a capacidade funcional (TGlittre e TC6min), qualidade de vida (QV) através do questionário World Health Organization Quality of Life Group Old (WHOQOL-OLD) e força de preensão manual (FPM). O TGlittre apresentou correlação com a idade dos participantes (p = 0,0040) e com o TC6min (p = 0,0086), entretanto não foi encontrada diferença estatística no tempo de execução do TGlittre e na distância percorrida no TC6min entre os grupos. O TGlittre não se correlacionou com a FPM (p = 0,1493) e com o WHOQOL-Old (p = 0,0905). Os dados obtidos no presente estudo corroboram para que o TGlittre seja utilizado como uma variável de medida funcional na população idosa. (AU)

The Glittre ADL-test (TGlittre) has been designed and validated to measure functional capacity during daily living activities in patients with chronic obstructive pulmonary disease (COPD) but is now used in several other situations. The aim of this study was to evaluate the applicability of TGlittre in a sample of overweight and obese eutrophic elderly. This was an experimental and cross-sectional study, which included 21 elderly women, allocated by BMI, in eutrophic (n = 8), overweight (n = 6) and obese (n = 7) groups. They were assessed for functional capacity (TGlittre and 6MWT), quality of life (QOL) with the questionnaire World Health Organization Quality of Life for Older People (WHOQOL-OLD) and handgrip strength (HGS). TGlittre correlated with age (p = 0.0040) and with 6MWT (p = 0.0086), but no statistical difference was found in TGlittre's performance time and the distance covered in 6MWT between groups. TGlittre did not correlate with HGS (p = 0.1493) and WHOQOL-Old (p = 0.0905). The data obtained in the present study corroborate that TGlittre is used as a functional measurement variable in the elderly population. (AU)

Quantification of DNA Damage in Different Tissues in Rats with Heart Failure / Quantificação de Dano em DNA em Diferentes Tecidos em Ratos com Insuficiência Cardíaca

Abstract Background: Chronic heart failure (CHF) is a complex syndrome which comprises structural and functional alterations in the heart in maintaining the adequate blood demand to all tissues. Few investigations sought to evaluate oxidative DNA damage in CHF. Objective: To quantify the DNA damage using the comet assay in left ventricle (LV), lungs, diaphragm, gastrocnemius and soleus in rats with CHF. Methods: Twelve male Wistar rats (300 to 330 g) were selected for the study: Sham (n = 6) and CHF (n = 6). The animals underwent myocardial infarction by the ligation of the left coronary artery. After six weeks, the animals were euthanized. It was performed a cell suspension of the tissues. The comet assay was performed to evaluate single and double strand breaks in DNA. Significance level (p) considered < 0.05. Results: The CHF group showed higher values of left ventricle end-diastolic pressure (LVEDP), pulmonary congestion, cardiac hypertrophy and lower values of maximal positive and negative derivatives of LV pressure, LV systolic pressure (p < 0.05). CHF group showed higher DNA damage (% tail DNA, tail moment and Olive tail moment) compared to Sham (p < 0.001). The tissue with the highest damage was the soleus, compared to LV and gastrocnemius in CHF group (p < 0.05). Conclusion: Our results indicates that the CHF affects all tissues, both centrally and peripherically, being more affected in skeletal muscle (soleus) and is positively correlated with LV dysfunction.

Resumo Fundamento: A insuficiência cardíaca crônica (ICC) é uma síndrome complexa que compreende alterações estruturais e funcionais no coração, mantendo demanda sanguínea adequada a todos os tecidos. Poucas investigações procuraram avaliar o dano oxidativo ao DNA na ICC. Objetivo: Quantificar o dano ao DNA utilizando o ensaio cometa no ventrículo esquerdo (VE), pulmões, diafragma, gastrocnêmio e sóleo em ratos com ICC. Métodos: Doze ratos Wistar machos (300 a 330 g) foram selecionados para o estudo: placebo (n = 6) e ICC (n = 6). Os animais foram submetidos a infarto do miocárdio através de ligadura da artéria coronária esquerda. Após seis semanas, os animais foram sacrificados. Foi realizada uma suspensão celular dos tecidos. O ensaio cometa foi realizado para avaliar as quebras de fita simples e dupla no DNA. Nível de significância (p) < 0,05. Resultados: O grupo ICC apresentou maiores valores de pressão diastólica final do ventrículo esquerdo (PDFVE), congestão pulmonar, hipertrofia cardíaca e menores valores de derivados máximos positivos e negativos da pressão do VE, pressão sistólica do VE (p < 0,05). O grupo ICC apresentou maior dano ao DNA (% de DNA da cauda, momento da cauda e momento da cauda de Olive) em comparação ao placebo (p < 0,001). O tecido com maior dano foi o sóleo, comparado ao VE e ao gastrocnêmio no grupo ICC (p < 0,05). Conclusão: Nossos resultados indicam que a ICC afeta todos os tecidos, de maneira central e periférica, sendo mais afetada no músculo esquelético (sóleo) e está positivamente correlacionada com a disfunção do VE.

Efeito agudo e crônico do treinamento aquático nas variáveis hemodinâmicas de pacientes cardiopatas: uma análise retrospectiva / Acute and chronic effects of aquatic training on hemodynamic variables of cardiac patients: a retrospective analysis

Introdução: A Insuficiência Cardíaca é uma patologia causada por várias desordens estruturais e funcionais que resultam na intolerância ao exercício, porém o treinamento aquático tem-se mostrado um importante método para a reabilitação de cardiopatas. Objetivo: Avaliar o comportamento hemodinâmico agudo e crônico de pacientes cardiopatas submetidos a um protocolo de treinamento aquático. Material e métodos: A amostra foi constituída por seis indivíduos com diagnóstico de cardiopatia, com idade de 68,3 ± 8,9 anos. Foram levantados dados dos prontuários referentes a características da amostra, pressão arterial sistólica (PAS), pressão arterial diastólica (PAD), frequência cardíaca (FC) e duplo produto (DP) pré e pós-sessão de treinamento aquático com frequência de duas vezes semanais, durante noventa dias. Resultados: Quanto ao efeito agudo, observou-se um aumento da FC no 2º (p=0,001) no 3º mês (p=0,033) e um aumento do DP no 2º mês (p=0,033) e no 3º mês (p=0,028) no pós-exercício em relação ao pré-exercício. Quanto ao efeito crônico, observou-se aumento na FC entre o segundo e o terceiro mês (p=0,044). Conclusão: O treinamento aquático foi capaz de aumentar aguda e cronicamente a FC e o DP em pacientes cardiopatas, sem alterações na pressão arterial.

Introduction: The cardiac insufficiency is a pathology caused by many structural and functional disorders which result in exercise intolerance. However, the aquatic training has been shown as an important method used in rehabilitation programs for cardiac patients. Objective: To evaluate the acute and chronic hemodynamic behavior of cardiac patients performing an aquatic training protocol. Methods: The six investigated individuals were 68.3 ± 8.9 years old, all of them with cardiopathy diagnostic. The systolic and diastolic blood pressure and the heart rate data, before and after exercise, were taken from medical records. The training sessions were conducted twice a week, during 90 days. Results: The acute effect of exercise increased the heart rate during the second (p=0.001) and the third (p=0.033) months, and also increased the double-product during the same periods (p=0.033 and p=0.028, respectively), comparing data before and after exercise. The chronic effect was observed by the increase of the heart rate in the third month compared to the second (p=0.044). Conclusion: The acute and chronic effect of the aquatic training increased the heart rate and the double-product of cardiac patients without blood pressure variations.

Strength training protocols in hemiparetic individuals post stroke: a systematic review / Protocolos de treinamento de força em hemiparéticos após acidente vascular cerebral: revisão sistemática

Abstract Introduction: Hemiparesis is one of the main sequels of stroke. Evidence suggests that muscle strength exercises are important in rehabilitation programs for hemiparetic patients, but wide variation in previously studied protocols makes the most suitable choice difficult in clinical practice. Objective: The aim of this study was to investigate strength training protocols for people with hemiparesis after stroke. Methods: A systematic review of literature was performed in the PubMed, PEDro (Physiotherapy Evidence Database), SciELO (Scientific Electronic Library Online), and LILACS (Latin American and Caribbean Literature in Health Science) databases. Only controlled clinical studies that contained strength training protocols for hemiparesis after stroke were selected. Results: In total, 562 articles were found. Of them, 12 were accepted for the systematic review. Although strength training protocols are effective in hemiparetic patients, we did not found a standard method for strength training. Conclusion: This systematic revision highlights the lack of a standard protocol for strength training, considering the following training parameters: volume, intensity, frequency, series, and repetitions. Isotonic exercises are most commonly used.

Resumo Introdução: A hemiparesia é uma das principais sequelas do Acidente Vascular Cerebral (AVC). Evidências recentes sugerem que o treinamento de força (TF) é um método eficiente para ganho de força na população hemiparética, porém, a grande variação de parâmetros dentre os numerosos protocolos disponíveis tornam difícil a escolha do protocolo mais adequado a ser utilizado na prática clínica. Objetivo: Investigar e analisar os protocolos de treinamento de força (TF) para população hemiparética pós-AVC. Métodos: Foi realizada uma revisão sistemática da literatura, nos bancos de dados PubMed; PEDro (Physioterapyevidencedatabase); SciELO (Scientific Eletronic Library Online); LILACS (Literatura Latino-Americana e Caribe em Ciências da Saúde). Foram selecionados apenas estudos clínicos controlados que trouxessem protocolos de TF em paciente pós-AVC hemiparéticos. Resultados: 562 artigos foram encontrados destes, 12 foram incluídos na revisão sistemática. Apesar do TF ser efetivo para pacientes hemiparéticos, não se observa um protocolo padrão para aplicação dessa intervenção na população hemiparética pós AVC. Conclusão: essa revisão sistemática alerta para a falta de padronização dos protocolos em relação ao volume, intensidade, frequência, séries e repetições de treinamento. Os exercícios isotônicos são os mais utilizados.

Functional capacity in a rat model of heart failure: impact of myocardial infarct size.

NEW FINDINGS: What is the central question of this study? To the best of our knowledge, no studies have evaluated oxygen uptake, carbon dioxide production and exercise tolerance in rats that have undergone myocardial infarction classified by myocardial infarct (MI) size. What is the main finding and its importance? Oxygen uptake and exercise intolerance are MI size dependent, and classification based on MI size can distinguish rats with functional capacity impairment. Rats with a large MI (>40% of the left ventricle) might provide a good model for the testing of new therapies that have the potential to modify the variables of functional capacity. Oxygen uptake (V̇O2) and exercise tolerance in rats classified by myocardial infarct (MI) size are underexplored. The aim of this study was to evaluate V̇O2, carbon dioxide production (V̇CO2) and exercise tolerance in rats that had undergone myocardial infarction. Fourteen weeks after myocardial infarction or sham surgery, rats underwent an integrated approach to evaluation of left ventricular function and V̇O2/V̇O2V̇CO2V̇CO2, exercise tolerance and skeletal muscle weight. Based on determination of MI size, rats were assigned to sham-operated controls (Sham, n = 12), small myocardial infarction (SMI, n = 8) and large myocardial infarction (LMI, n = 5) groups. The LMI rats showed lower systolic (ejection fraction and fractional shortening) and diastolic (E/A ratio) left ventricular function compared with SMI. Maximal V̇O2 (∼24%, P < 0.05), V̇O2 reserve (∼30%, P < 0.05), time to exhaustion (∼36%, P < 0.05) and maximal velocity (∼30%, P < 0.05) were lower in LMI compared with sham-operated control animals, with no difference between SMI rats and sham-operated controls. Maximal V̇CO2 and respiratory exchange ratio showed no significant difference between MI rats and sham-operated control rats. The LMI rats demonstrated lower gastrocnemius weight (∼12%, P < 0.05) and soleus weight (∼19%, P = 0.07) compared with sham-operated control rats. Significant correlations between MI size, left ventricular end-diastolic pressure, right ventricle hypertrophy, pulmonary congestion, ejection fraction and fractional shortening with maximal V̇O2 and distance run were observed. Oxygen uptake and exercise intolerance are MI size dependent.

Maximal oxygen uptake and exercise tolerance are improved in rats with heart failure subjected to low-level laser therapy associated with resistance training.

Exercise tolerance and maximal oxygen uptake (VO2max) are reduced in heart failure (HF). The influence of combined resistance training (RT) and low-level laser therapy (LLLT) on exercise tolerance and VO2max in HF has not yet been explored. The aim of this study was to evaluate the influence of combined RT and LLLT on VO2max and exercise tolerance in rats with HF induced by myocardial infarction (MI). Rats were allocated to sedentary sham (Sed-Sham, n = 12), sedentary heart failure (Sed-HF, n = 9), RT heart failure (RT-HF, n = 7) and RT associated with LLLT heart failure (RT + LLLT-HF, n = 7) groups. After MI or sham surgery, rats underwent a RT and LLLT protocol (applied immediately after RT) for 8 weeks. VO2max and exercise tolerance were evaluated at the end of protocol. HF rats subjected to LLLT combined with RT showed higher VO2basal (41 %), VO2max (40 %), VO2reserve (39 %), run distance (46 %), time to exhaustion (30 %) and maximal velocity (22 %) compared with HF rats that underwent RT alone. LLLT associated with RT improved oxygen uptake and exercise tolerance compared with RT alone in HF rats.

Light-emitting diode therapy (LEDT) improves functional capacity in rats with heart failure.

The syndrome of heart failure (HF) promotes central and peripheral dysfunctions that result in functional capacity decrease, leading to fatigue, dyspnea, and exercise intolerance. The use of light-emitting diode therapy (LEDT) has shown good results reducing fatigue and exercise intolerance, when applied on skeletal muscles before or after exercises. Thereby, the aim of this study was to compare the effects of LEDT on functional capacity, aerobic power, and hemodynamic function in HF rats. Male Wistar rats (230-260 g) were randomly allocated into three experimental groups: Sham (n = 6), Control-HF (n = 4), and LEDT-HF (n = 6). The animals were subjected to an exercise performance test (ET) with gas analysis coupled in a metabolic chamber for rats performed two times (6 and 14 weeks after myocardial infarction). On the day after the baseline aerobic capacity test, the animals were submitted during 8 weeks to the phototherapy protocol, five times/week, 60 s of irradiation, 6 J delivered per muscle group. Statistical analysis was performed by one- and two-way ANOVAs with repeated measures and Student-Newman-Keuls post hoc tests (p ≤ 0.05). Comparing the percentage difference (Δ) between baseline and the final ET, there was no significant difference for the VO2max variable considering all groups. However, Sham and LEDT-HF groups showed higher relative values than the Control-HF group, respectively, for distance covered (27.7 and 32.5 %), time of exercise test (17.7 and 20.5 %), and speed (13.6 and 12.2 %). In conclusion, LEDT was able to increase the functional capacity evaluated by distance covered, time, and speed of exercise in rats with HF.

Long-term low-level laser therapy promotes an increase in maximal oxygen uptake and exercise performance in a dose-dependent manner in Wistar rats.

The use of low-level laser therapy (LLLT) represents a new intervention modality that has been explored to enhance exercise performance. The aim of this study was to evaluate the influence of LLLT (GaAIAs-850 nm) at different doses on VO2max and on exercise performance in rats. Male Wistar rats were divided into three groups: "placebo" rats (P-LLLT, n = 10), rats at a dose of 0.315 J per treatment point of LLLT (8.7 J/cm(2)-LLLT, n = 10), and rats at a dose of 2.205 J per treatment point of LLLT (61.2 J/cm(2)-LLLT, n = 10). The LLLT was applied bilaterally at the biceps femoris, gluteus, lateral and medial gastrocnemius, iliopsoas, and adductor longus muscles. One spot in each muscle belly was applied, with a sum of 12 spots in each rat, once a day, for 10 days. All animals performed the maximal exercise test (ET) at a metabolic treadmill for rats, with simultaneous gas analysis. The distance covered was measured during ET, before and after the conclusion of the LLLT protocol. The data were compared by a repeated measures two-way ANOVA followed by the Student-Newman-Keuls post hoc tests (p < .05). The 61.2 J/cm(2)-LLLT group increased VO2basal (~40 %), VO2max (~24 %), VCO2max (~17 %), and distance covered (~34 %) after LLLT application on the skeletal muscle. No significant results were found comparing before and after conditions for the studied variables considering P-LLLT and 8.7 J/cm(2)-LLLT groups. The LLLT promoted in a dose-dependent manner an increase in oxygen consumption uptake and a performance increment of male Wistar rats.

Ultrasound modulates skeletal muscle cytokine levels in rats with heart failure.

Heart failure is a multisystemic disorder that leads to an imbalance between pro- and anti-inflammatory cytokines. Therapeutic ultrasound (TU) has been reported to modulate the inflammatory process. The aim of this study was to evaluate the effect of TU on pro- and anti-inflammatory cytokine levels in soleus muscle and plasma of rats with heart failure. Thirty male Wistar rats (230-260 g) were submitted to ligation of the left coronary artery or sham surgery. Six weeks after surgery, TU was administered directly to the right lower limb. The results indicate that TU promotes reduction of pro-inflammatory cytokine levels (tumor necrosis factor α, interleukin-6) and increases anti-inflammatory cytokine levels (interleukin-10) in the soleus muscle of rats with heart failure. This is the first study to find that TU can modulate cytokine levels in rats with heart failure. Additionally, this is a first report that TU can modulate interleukin-10 levels in the soleus muscle.