Analysis of co-contraction of the trunk muscles in the side bridge stabilization exercise with different unstable surfaces

The muscle co-contraction is a phenomenon characterized by the simultaneous contraction of two or more muscles around a joint. The objective of this study was to compare the antagonist co-contraction of the local and global trunk muscles during side bridge exercise, in four situations: (a) stable; (b) instability in the upper limbs with bosu; (c) instability in the upper limbs with disc and (d) double instability. The sample consisted of 20 male volunteers and data collection was performed with simple differential surface electrodes. The electromyographic activity was collected from the Rectus Abdominis (RA), Internal Oblique Abdominis (IO), Multifidus (MF) and Erector Spinae (ES). Were utilized specific routines developed in the Matlab program (Mathworks Natick, USA) to calculate the percentage of antagonist co-contraction between local (IO/MF) and global muscles (RA/ES). The collected data were submitted to parametric statistical analysis (repeated measures ANOVA) or non-parametric (Friedman). The results demonstrated that no significant differences were observed in the pattern of global and local co-contraction in the different side bridge exercises with and without unstable surface. It is concluded that the use of unstable surface in the side bridge stabilization exercise does not increase the level of co-contraction of the trunk flexor and extensor muscles compared to normal stability. However, future studies should use a longer time of isometric contraction in trunk stabilization exercises to optimize the understanding of the effects of different unstable equipment on global and local levels of co-contraction of the trunk muscles

Electromyography of the abdominal muscles and rectus femoris in abdominal exercises with and without the unstable surfaces

The abdominal exercises are performed to the preventing and/or rehabilitation of lower back pain, improved athletic performance, increased strength and resistance of the trunk during the performance of activities of daily living and aesthetics. The objective was to analyze and compare the electromyographic activity of the upper (URA) and lower rectus abdominis (LRA), external oblique (EO), internal oblique (IO) and rectus femoris (RF) during traditional abdominal exercise with and without using the bosu and gymnastics ball. The sample was composed of 10 male volunteers, active physically and without neuromuscular disorder. Data collection was performed using a single differential surface electrodes, with a gain of 20 times, and recorded by a computerized electromyography. The electromyographic signal was quantified by the Root Mean Square (RMS) and normalized (RMSn) by maximal voluntary isometric contraction. The data were subjected to parametric statistical analysis, using the analysis of variance (ANOVA) for repeated measures. The results showed that the URA muscle activity in the exercise with bosu was significantly higher compared to the traditional (p < 0.05), however, for the LRA, EO, IO and RF muscles, there were no significant differences (p > 0.05) among all abdominal exercises (traditional, bosu and gymnastics ball). We conclude that the use of the bosu in the abdominal exercises can be a necessary and desirable factor in specific stages of rehabilitation programs and / or physical training, mainly to increase the recruitment of the upper (URA) rectus abdominis muscle.Os exercícios abdominais são realizados visando a prevenção e/ou reabilitação de dores na região lombar, a melhoria do rendimento atlético, aumento da resistência e força do tronco durante o desempenho das atividades da vida diária e pela estética. Objetivou-se analisar e comparar a atividade eletromiográfica dos músculos rectus abdominis parte superior (RAS) e parte inferior (RAI), obliquus externus abdominis (OE), obliquus internus abdominis (OI) e rectus femoris (RF) durante o exercício abdominal tradicional com e sem a utilização do bosu e bola de ginástica. A amostra foi composta por dez voluntários do gênero masculino, fisicamente ativos e sem distúrbio neuromuscular. A coleta de dados foi realizada utilizando-se eletrodos de superfície diferenciais simples, com ganho de 20 vezes, e registrada por meio de um eletromiógrafo computadorizado. O sinal eletromiográfico foi quantificado pela Raiz Quadrada da Média (Root Mean Square [RMS]) e normalizado (RMSn) pela Contração Isométrica Voluntária Máxima. Os dados foram submetidos à análise estatística paramétrica, empregando-se teste de análise de variância de medidas repetidas (Anova). Os resultados demonstraram que atividade do músculo RAS no exercício com bosu foi significativamente maior em relação ao tradicional (p < 0.05), todavia, não foram encontradas diferenças significativas (p > 0.05) para músculos RAI, OE, OI e RF, entre todos exercícios abdominais (tradicional, bosu e bola de ginástica). Conclui-se que a utilização do bosu no exercício abdominal pode ser um fator desejável e necessário em estágios específicos de programas de reabilitação e/ou treinamento físico, principalmente quando objetiva-se aumentar o recrutamento da parte superior do músculo rectus abdominis (RAS)

Association between obesity and knee osteoarthritis in users of brazilian unified national health system

Verify possible associations between obesity and knee OA in users of Brazilian Unified National Health System (Sistema Único de Saúde - SUS) of primary care network in Catalão-GO, Brazil. This is an observational study conducted in 2014 and 2015. A total of 81 volunteers from the Basic Attention Network in the city of Catalão, with body mass index (BMI) over 30 kg/m2 in both sexes, age between 40 and 60 years, and OA on radiological examination of the knee. Obesity was classified according to BMI. The diagnosis of osteoarthritis (OA) was made clinically and by radiography according to Kellgren radiological classification. The level of physical activity was assessed using the Baecke questionnaire and the Gordon Functional Classification. The volunteers underwent an anthropometric evaluation and physical examination with inspection and palpation of the joint and subsequent radiological examination of the knee. The volunteers answered a questionnaire on the level of physical activity and functional classification. Data analysis was performed using Fisher’s exact test or chi-square test was used for comparisons of two proportions. In comparisons of continuous variables, Student’s t-test or the nonparametric Wilcoxon-Mann-Whitney test was used. The level of significance was set to 5%. Practice of regular physical exercise decreases functional impairment in obese individuals with knee OA. The weight variable demonstrated a strong association with the severity of OA and degree of functionality of patients. Obesity and OA durations and lack of patient guidance are variables that may contribute to the progression of knee OA. Although the incidence among men is lower, they are more severely affected and anthropometric evaluation and physical examination are an efficacy implementations for Brazilian users of SUS

Eletromyography of abdominal muscles in different physical exercises: An update protocol for systematic review and meta-analysis

Background:The abdominal muscles are extremely important because they are directly involved in the functions of support, containment of viscera, and help in the process of expiration, defecation, urination, vomiting, and also at the time of childbirth. Many exercises and equipment are used to strengthen the abdominal muscles, and the workouts are proposed for a variety of purposes, such as preventing and rehabilitating low back pain, improving sports performance, achieving aesthetic standards, among others. Exercises that potentiate the electromyographic activity promote a greater recruitment of muscle fibers and are more effective to improve or maintain of the force. The electromyographic activity analysis allows us to reflect on the quality of the exercises proposed, consequently, to choose and order the exercises properly in a training session.Methods:Our systematic review protocol will developed following the reporting items for the systematic review. To identify relevant studies, we sought articles on the following bases: MEDLINE, PubMed, Europubmed, SciELO, Physiotherapy Evidences Data Base (PEDro), Cochrane, and Google Scholar. The methodological quality of the studies included in the review will evaluated using a checklist and quality assessment. For intervention studies, risk of bias will estimated using the Cochrane Collaboration tool.Results:The results of this study will show the electromyographic activation of the abdomen in the different types of exercises.Conclusion:Ethics approval was not required for this study because it was based on published studies. The results and findings of this study will be submitted and published in a scientific peer-reviewed journal.Systematic review registration:PROSPERO CRD42018086172.Univ Fed Uberlandia, Inst Biomed Sci, Electromyog Lab, Uberlandia, MG, BrazilUniv Fed Uberlandia, Lab Expt Med, Uberlandia, MG, BrazilUniv Fed Goias, Dept Biol Sci, Catalao, BrazilUNIPAC Coll Uberlandia, Uberlandia, MG, BrazilUniv Fed Uberlandia, Coll Phys Educ, Uberlandia, MG, BrazilAtenas Coll, Morphofunct Dept, Paracatu, BrazilUniv Fed Sao Paulo, Dept Biosci, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Biosci, Sao Paulo, BrazilWeb of Scienc

Leucine Supplementation Improves Effort Tolerance of Rats With Hyperthyroidism

Leucine is a regulator of protein metabolism in vivo and information on its action on effort tolerance of both animals and humans with hyperthyroidism is scarce. The objective of the present study was to verify the influence of leucine supplementation on the effort tolerance of Wistar rats with experimental hyperthyroidism. 40 animals were divided into four groups of ten: control (C), hormone (H), leucine (L), and hormone + leucine (HL). Hyperthyroidism was induced by daily administration of 20 μ⋅g100 g-1 of levothyroxine sodium in aqueous suspension by gavage. Leucine was supplemented by adding 5% of the amino acid to the conventional feed. The animals’ blood was collected by cardiac puncture to analyze TSH, T4, and T3 levels. The effort tolerance was determined by the swimming test with a 7% load attached to animals’ tails. Statistical analysis was performed using the Shapiro-Wilk normality test, followed by the analysis of variance (ANOVA) of repeated measures of two factors (treatment × time) and Tukey post hoc, with a significance level of p < 0.05. Administering thyroid hormone increased the swimming performance of rats after 14 and 21 days, but with a drop in performance at 28 days. The HL group, on the other hand, had a significantly higher swimming performance compared to the other groups after 28 days of treatment. Leucine supplementation associated with the experimental model of hyperthyroidism improved the performance of rats in a swimming test after 28 days of treatment

Origin and distribution of the axillary nerves in zebu-crossed bovine fetuses

In this study, the origin and distribution of the axillary nerve in 30 fetuses of zebu-crossed bovines, 20 males and 10 females, were analyzed through dissection after fixation in an aqueous solution of 10% formaldehyde. The axillary nerve was found to originate in 13.33% of the antimeres of the ventral branch of the 6th cervical (C6) spinal nerve, in 100% of the antimeres of the ventral branch of the 7th cervical (C7) spinal nerve, in 91.67% of the ventral branch of the 8th cervical (C8) spinal nerve, and in 5.00% of the ventral branch of the 1st thoracic (T1) spinal nerve. The axillary nerve extended branches to the teres minor (100,00%), deltoid (100,00%), cleidobrachial part of the brachiocephalic muscle (100,00%), subscapularis (78.33%) and teres major (11.66%) muscles. In all the animals, the aforementioned nerve issued the cranial cutaneous branch of the lower leg, which was distributed to the fascia and skin of the cranial face of the upper and lower leg. No significant differences were found in the frequency of branches of the axillary nerves issuing to the muscles of the right and left antimeres. However, statistically significant differences were found in the frequency of branches leading to the right deltoid muscle in males and females, with male fetuses showing a higher frequency of these branches.Mestre em Ciências VeterináriasNeste estudo foram analisadas por meio da dissecação a origem e distribuição do nervo axilar em 30 fetos de bovinos azebuados, 20 machos e 10 fêmeas, após a fixação em solução aquosa de formaldeído a 10%. O nervo axilar originou-se em 13,33% dos antímeros do ramo ventral do sexto nervo espinal cervical (C6), em 100% dos antímeros do ramo ventral do sétimo nervo espinal cervical (C7), em 91,67% do ramo ventral do oitavo nervo espinal cervical (C8) e em 5,00% do ramo ventral do primeiro nervo espinal torácico (T1). O nervo axilar cedeu ramos para os músculos redondo menor (100,00%), deltóide (100,00%), parte cleidobraquial do músculo braquiocefálico (100,00%), subescapular (78,33%) e redondo maior (11,66%). Em todos os animais o referido nervo emitiu o ramo cutâneo cranial do antebraço, o qual distribuiu- se para a fáscia e pele da face cranial do braço e antebraço. Não houve diferenças significativas entre as freqüências de ramos dos nervos axilares emitidos para os músculos dos antímeros direito e esquerdo, entretanto, constataram-se diferenças estatísticas entre a freqüência de ramos cedidos para o músculo deltóide direito em machos e fêmeas, sendo observada uma maior freqüência para os fetos machos

Origin and distribution of the axillary nerve in the giant anteater (Myrmecophaga tridactyla)

The giant anteater (Myrmecophaga tridactyla), a mammal belonging to the order Xenarthra and family Myrmecophagidae, is an endangered species. For this reason, additional knowledge about its anatomy is of interest, especially the forelimb, which plays important roles in feeding and defense. The goal of this study was to learn more about the origin and distribution of the axillary nerve of Myrmecophaga tridactyla by studying two individuals (one male and one female) that belong to the Research Laboratory of Wild Animals (UFU). The study material consisted of corpses fixed and preserved in 10% aqueous formalin solution. Dissection of the material followed standard procedures. In both animals, the axillary nerve was found in the ventral branch of the sixth cervical (C6) and seventh (C7) spinal nerve. This nerve showed symmetry in relation to its position in the two specimens and branched into the teres major, teres minor and deltoid muscles. In both specimens the axillary nerve originated in the cranial cutaneous branch of the lower leg

Origem e distribuição do nervo isquiático em fetos de suínos (Sus scrofa domesticus – Linnaeus, 1758) da linhagem Pen Ar Lan

http://dx.doi.org/10.5007/2175-7925.2013v26n1p147Estudou-se a origem e distribuição do nervo isquiático em 31 fetos de suínos da linhagem Pen Ar Lan, sendo 22 machos e nove fêmeas, após ser fixados em solução aquosa de formaldeído a 10%. Nesses, animais, as vértebras lombares variaram de cinco a sete, com predominância de seis, o que contribuiu para variações na origem do referido nervo. O nervo isquiático originou-se em 80,64% dos antímeros, do ramo ventral do quinto nervo espinhal lombar (L5); em 96,77% de L6; em 6,45% de L7; em 100% de S1; e em 64,51% de S2. A composição do referido nervo ocorreu em 45,16% dos animais pela união de L5, L6, S1 e S2; em 32,25% de L5, L6 e S1; em 12,90% de L6, S1 e S2; em 6,45% de L6, L7 e S1; e em 3,22% de L5, S1 e S2. Houve simetria na origem do nervo isquiático em todos os espécimes estudados. Esse nervo emitiu ramos para os músculos glúteo superficial, semitendinoso, semimembranoso e bíceps femoral em todos os espécimes, e em menor frequência, para os músculos gêmeos, quadrado femoral, adutores, e glúteos médio, acessório e profundo. Em 74,19% da amostra, foi observado um ramo comunicante com nervo pudendo