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)

Health-status outcomes with invasive or conservative care in coronary disease

BACKGROUND In the ISCHEMIA trial, an invasive strategy with angiographic assessment and revascularization did not reduce clinical events among patients with stable ischemic heart disease and moderate or severe ischemia. A secondary objective of the trial was to assess angina-related health status among these patients. METHODS We assessed angina-related symptoms, function, and quality of life with the Seattle Angina Questionnaire (SAQ) at randomization, at months 1.5, 3, and 6, and every 6 months thereafter in participants who had been randomly assigned to an invasive treatment strategy (2295 participants) or a conservative strategy (2322). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate differences between the treatment groups. The primary outcome of this health-status analysis was the SAQ summary score (scores range from 0 to 100, with higher scores indicating better health status). All analyses were performed in the overall population and according to baseline angina frequency. RESULTS At baseline, 35% of patients reported having no angina in the previous month. SAQ summary scores increased in both treatment groups, with increases at 3, 12, and 36 months that were 4.1 points (95% credible interval, 3.2 to 5.0), 4.2 points (95% credible interval, 3.3 to 5.1), and 2.9 points (95% credible interval, 2.2 to 3.7) higher with the invasive strategy than with the conservative strategy. Differences were larger among participants who had more frequent angina at baseline (8.5 vs. 0.1 points at 3 months and 5.3 vs. 1.2 points at 36 months among participants with daily or weekly angina as compared with no angina). CONCLUSIONS In the overall trial population with moderate or severe ischemia, which included 35% of participants without angina at baseline, patients randomly assigned to the invasive strategy had greater improvement in angina-related health status than those assigned to the conservative strategy. The modest mean differences favoring the invasive strategy in the overall group reflected minimal differences among asymptomatic patients and larger differences among patients who had had angina at baseline

Initial invasive or conservative strategy for stable coronary disease

BACKGROUND Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, 121.8 percentage points; 95% CI, 124.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used