Maximal isokinetic peak torque and EMG activity determined by shorter ranges of motion

Purpose. Isokinetic tests are often applied to assess muscular strength and EMG activity, however the specific ranges of motion used in testing (fully flexed or extended positions) might be constrictive and/or be painful for patients with injuries or under-going rehabilitation. The aim of this study was to examine the effects of different ranges of motion (RoM) when determining maximal EMG during isokinetic knee flexion and extension with different types of contractions and velocities. Methods. Eighteen males had EMG activity recorded on the vastus lateralis, vastus medialis, semitendinosus and biceps femoris muscles during five maximal isokinetic concentric and eccentric contractions for the knee flexors and extensors at 60° • s -1 and 180° • s -1. The root mean square of EMG was calculated at three different ranges of motion: (1) a full range of motion (90°-20° [0° = full knee extension]); (2) a range of motion of 20° (between 60°-80° and 40°-60° for knee extension and flexion, respectively) and (3) at a 10° interval around the angle where peak torque is produced. EMG measurements were statistically analyzed (ANOVA) to test for the range of motion, contraction velocity and contraction speed effects. Coefficients of variation and Pearson's correlation coefficients were also calculated among the ranges of motion. Results. Predominantly similar (p > 0.05) and well-correlated EMG results (r > 0.7, p ≤ 0.001) were found among the ranges of motion. However, a lower coefficient of variation was found for the full range of motion, while the 10° interval around peak torque at 180° • s -1 had the highest coefficient, regardless of the type of contraction. Conclusions. Shorter ranges of motion at around the peak torque angle provides a reliable indicator when recording EMG activity during maximal isokinetic parameters. It may provide a safer alternative when testing patients with injuries or undergoing rehabilitation.

Evaluation of peak cough flow in Brazilian healthy adults

Introduction. In this study we aimed to evaluate the peak cough flow (PCF) in healthy Brazilian subjects. Methods. We evaluated 484 healthy subjects between 18 and 40 years old. Subjects were seated and oriented were asked to perform a maximal inspiration followed by a quick, short and explosive expiration on the peak flow meter. Three measures were carried out and recorded the average of the three results for each individual. Results: The PCF values ranged between 240 and 500 L/min. The PCF values were lower in females than in males. The PCF was inversely proportional to age. Conclusion: The values for Brazilian adult healthy subjects regarding PCF were between 240 and 500 L/min. © 2012 Cardoso et al.; licensee BioMed Central Ltd.

Las perspectivas de la producción y de la demanda de productos siderúrgicos laminados en América Latina = Rolled iron and steel products in Latin America: prospective production and demand

Incluye Bibliografía

Education in Latin America: demand and distribution are factors that matter

Includes bibliography

Heterogeneous demand and market segmentation: the Argentine pension funds system

Includes bibliography

Differential fuel taxes and their effects on automobile demand

Includes bibliography

The economics of demand-led growth: theory and evidence for Brazil

Includes bibliography

Capital goods: size of markets, sectoral structure and demand prospects in Latin America

Includes bibliography

Energy demand in Chilean manufacturing

Includes bibliography

The acute effects of static stretching on peak force, peak rate of force development and muscle activity during single- and multiple-joint actions in older women

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Flexibility, torque and kick performance in soccer: Effect of dominance

Aim: The aim of this study was to evaluate the knee flexor and extensor torques in isometric contractions, comparing the H:Q ratios, flexibility and maximal kick between dominant (DL) and non-dominant (NDL) limb of soccer players (SG) and active people (AG)Methods: Subjects performed maximal instep kicks with each limb, flexibility tests and maximal isometric voluntary contractions of the knee flexion and extension at 45° and 90° to determine peak torque of the DL and NDLKnee flexion torque was divided by the knee extension torque to calculate torque ratios (H:Q ratio)Results: The flexibility and maximal kick in SG was significantly higher than in AG for both the DL and NDL (P<0.05)The maximal kick of DL was significantly higher than in NDL in SG (P<0.01)Knee flexion torque in SG was significantly higher than in AG in the DL (P<0.05), and the H:Q ratio was similar between AG and SGConclusion: Dominance related differences were evident in the flexor torque and maximal kick for SG, probably related to the asymmetric demand in trainings, which present no effect on the flexibility© 2013 Elsevier Masson SAS.

Methodology for forecasting electric power demand

Includes bibliography

Implementação de um controle digital para o compensador regenerativo de potência ativa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Latin American supply and major world market demand for the principal metals, 1970-1990: aluminium, copper, iron, nickel, lead, zinc, tin

Includes bibliography

Análise de controladores eletrônicos em sistemas de distribuição de energia

Pós-graduação em Engenharia Elétrica - FEIS