Electromyographic validation of the double pulley equipment during movements of the lower limbs

The double pulley equipment was tested on ten male volunteers during contraction of the semitendinosus and biceps femoris (caput longum) muscles in the following movements of the lower limbs: 1) hip extension with extended knee and erect trunk, 2) hip extension with flexed knee and erect trunk, 3) hip extension with flexed knee and erect trunk, 3) hip extension with extended knee and inclined trunk, 5) hip abduction along the midline, 7) hip abduction with extension beyond the midline, 8) adduction with hip flexion beyond the midline, 8) adduction with hip flexion beyond the midline, and 9) adduction with hip extension beyond the midline. The myoelectric signals were taken up by Lec Tec surface electrodes connected to a 6-channel Lynx electromyographic signal amplifier coupled with a computer equipped with a model CAD 10/26 analogue digital conversion board and with a specific software for signal recording and analysis. The semitendinosus and biceps femoris muscles presented the highest potentials in movements 1; 2; 7, 8 and 9, whereas the potentials in the remaining movements were negligible. The pattern of activity of the semitendinosus and the biceps femoris was similar in exercises 1, 2, 3, 4 and 8. The potentials of the semitendinosus prevailed in movements 5, 6 and 7, and the strongest potentials observed in movement 9 were those of the biceps femoris.

Electromyographyc evaluation of movements of lower limb in double pulley system equipment: Comparison between gastrocnemius (caput laterale) and gluteus maximus

It was evaluated movements of lower limb in the double pulley system equipment on ten male volunteers during contraction of gastrocnemius (caput laterale ) and gluteus maximus muscles in the following movements: 1) hip extension with extended knee and erect trunk, 2) hip extension with flexed knee and erect trunk, 3) hip extension with flexed knee and erect trunk, 3) hip extension with extended knee and inclined trunk, 5) hip abduction along the midline, 7) hip abduction with extension beyond the midline, 8) adduction with hip flexion beyond the midline, 8) adduction with hip flexion beyond the midline, and 9) adduction with hip extension beyond the midline. Myoelectric signals were taken up by Lec Tec surface electrodes connected to a 6-channel Lynx electromyographic signal amplifier coupled with a computer equipped with a model CAD 10/26 analogue digital conversion board and with a specific software for signal recording and analysis. We observed weak gastrocnemius muscle activity for all movements studied. In the case of gluteus maximus, the most important potentials were observed for movement 2, while for the remaining movements the actions were of reasonable intensity. Compared to gluteus, gastrocnemius was less required for all movements.

Influence of exercise order on upper body maximum and submaximal strength gains in trained men

The purpose of this study was to investigate the influence of exercise order on one-repetition maximum (1-RM) and ten-repetition maximum (10-RM) strength gains after 6 weeks of resistance training (RT) in trained men. Sixteen men were randomly assigned into two groups based on the order of exercises performed during training sessions: a group that performed large muscle group exercises first and progressed to small muscle group exercises (LG-SM); while a second group performed the opposite sequence and started with small muscle group exercises and progressed to large muscle group exercises (SM-LG). Four sessions of RT were conducted per week; all exercises were performed for three sets of 8-12 repetitions with 1-min rest intervals between sets. Maximal and submaximal strength were assessed at baseline and after 6 weeks of RT with 1-RM and 10-RM testing for the bench press (BP), lat pulldown (LPD), triceps pulley extension (TE) and biceps curl (BC), respectively. Two-way ANOVA for the 1-RM and 10-RM tests indicated a significant group x time interaction. The 1-RM values significantly increased for all exercises in both groups (P<0.05), but were not significantly different between groups. However, effect size (ES) data indicated that the LG-SM group exhibited a greater magnitude of gains (1-RM and 10-RM) for the BP and LPD exercises. Conversely, ES indicated that the SM-LG group exhibited a greater magnitude of gains (1-RM and 10-RM) for the TE and BC exercises. In conclusion, the results suggest that upper body movements should be prioritized and performed according to individual needs to maximize maximal and submaximal strength. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine.

Efeito do exercício com pesos em diferentes intensidades e volumes na sensibilidade à dor em idosas hipertensas e normotensas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito agudo dos exercícios com pesos sobre os níveis de leptina, adiponectina e fator de necrose tumoral alfa em adultos não treinados

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

Diferenciação hemogasimétrica, hemoconcentradora e da glicemia em testes de exaustão muscular usando cinco, quatro ou três exercícios

Em trabalho anterior, observou-se que diferentes grupamentos musculares submetidos ao teste de exaustão (TE) com pesos respondem semelhantemente com hemoconcentração, acidose e aumento da glicemia, entretanto, com variações grupomuscular dependentes. Nesse estudo, é comparado o efeito do impacto provocado pelo TE envolvendo, conjuntamente, 5, 4 ou 3 exercícios por meio da análise desses marcadores bioquímicos. Foram estudados 21 indivíduos do sexo masculino (20-32 anos) voluntários, familiarizados com treinamento em musculação, estratificados em três grupos de acordo com o número de exercícios: grupo 5 ( n= 6) 5 exercícios (Extensão do cotovelo, desenvolvimento pela frente, supino reto, levantamento terra e agachamento), grupo 4 (n= 7) 4 exercícios (Supino reto, rosca direta com barra, agachamento hack, tríceps no pulley), grupo 3 (n= 8) 3 exercícios (Agachamento hack, supino reto, rosca direta ) . Todos foram submetidos à sobrecarga inicial de 80% de uma repetição máxima (1RM), até a exaustão, em seguida, com auxílio externo e sem interrupção do exercício, a carga foi reduzida em 20% do peso, até a impossibilidade de continuidade de realização do exercício com a carga mínima (20% de 1RM). O sangue coletado em veia cubital antes (At) e imediatamente após (Ap) o TE foi analisado para indicadores hemogasimétricos (pH, pO2, pCO2, HCO- 3), hemoconcentração (Ht) e glicemia. O efeito do TE sobre cada variável (At/Ap) foi avaliado comparando-se os grupos por meio de ANOVA-medidas repetidas para significância de p=0,05. Houve significância (p<0,05) na elevação do Ht, glicose e pO2 e redução do pH, PCO2 e HCO- 3, Entretanto houve diferença significativa entre os grupos apenas em relação ao HCO- 3, no qual este apresentou maior variação no G4 em relação ao demais. Assim, esses marcadores sistêmicos respondem a exaustão muscular de modo semelhante ao envolvimento de 3,4 ou 5 grupamentos musculares

Uma análise da eficiência de uma transmissão CVT

This undergraduate thesis evaluates the effects of temperature variation of the air inside the CVT gearbox on the performance of a Continuously Variable Transmission (CVT). The CVT used in the tests was manufactured by Gaged Engineering (GX9 model) and is currently used in a Baja prototype. It’s a mechanically operated CVT, which the movement of the pulley plates varies according to the drive shaft rotation, shifting the belt along the diameter, and varying the transmission ratio. The purpose of this work is to analyze the change in the slip factor, coefficient that compares the variation between the actual transmission ratio and the ratio of geometric transmission, and its correlation with the power variation. A test bench was built and some tests were performed, indicating that was possible to achieve output power ratios of 1.75 [ℎ

Redução do tempo de setup de máquinas de usinagem em uma industria automobilística

Continuous improvement of industrial processes is one way to become companies more competitive in the market. For this, a fairly widespread use is the methodology of lean production systems, by eliminating waste. One of the tools of these systems is the method of rapid exchange of die or also called SMED, which will be applied in this study. The study aims to develop proposals for reducing the time of set up of two machines in two machining lines, watching also the ergonomics and safety conditions in this operations. The set up time reduction is justified among others, due to increase the machine productivity. In applying the connecting rod machining line, there were two types of exchange. Reductions in time to set up proposals reached values of 47% to one of them, and 55% to the other. It is important to underline that to reach this result, there was no need for large investments. In the application in block machining line, was developed an improvement in the ergonomic area. It was placed a pulley block that came to increase the time of tool change. Aiming to improve the security of the exchange, without productivity loss, the method was applied to reduce this time. It was developed two proposals.: the first would reduce that time by 19%, and does not require many resources of the company. The second involves the parallelization of the exchange, so that the reduction is 48%. However, this proposal requires one more manpower at the time of exchange and it is not always possible

Análise da cinética do VO2 no domínio severo do crawl em condição atada de nado

Pós-graduação em Desenvolvimento Humano e Tecnologias - IBRC

Capacidade de força dos membros superiores em competidores de montaria em touros

This study did evaluate the handgrip strength capacity of bull riding practitioners and recreational practitioners in order to obtain parameters of the muscular fitness of subjects undertaken this sports practice. Twenty right-handed subjects were grouped into bull riding athletes (10 individuals at AMT: 174.5 ± 5.2 cm of height, 78.9 ± 12 kg of body weight, 24.7 ± 6.1 years, and 13,8 ± 2.4% for body fat) and non-athletes (10 subjects n-AMR: 178.5 ± 7.3 cm of height, 81.2 ± 8.8kg of body weight, 21.7 ± 2.3 years, and 13.8 ± 1.9% of body fat). They were underwent to protocols of handgrip strength evaluation by a standard and specific dynamometry (simulating a bull riding posture) of right (DPD e DED) e left (DEP e DEE) hands. The dynamic force values from one repetition to maximum test (1RM) were either obtained in conventional load-based system for upper limbs exercises. The values were compared by the test-t for independent data, assuming ρ ≤ 0.05. The relationship between the values of strength from handgrip and dynamic exercises were drawn by Pearson correlation. The results of the AMT to DPD (43.8 ± 6.8kgf), DPE (39.4 ± 7.7kgf), DED (44.9 ± 5.6kgf), and DEE (39.8 ± 8.3kgf). For the n-AMT in DPD (47.0 ± 3.0kgf), DPE (42.2 ± 6.1kgf), DED (49.2 ± 1.5kgf), and DEE (46.2 ± 4.1kgf). Significant difference was observed between DED and DEE. The strength tests of 1RM at bench press (73.2 ± 12.0kg and 82.0 ± 12.0kg), arm-curl (45.2 ± 8.9kg and 43.8 ± 8.9kg), triceps pulley (67.0 ± 6.3kg and 72.0 ± 6.3kg), and pulley (73.5 ± 8.5kg and 73.7 ± 7.5kg) for groups n-AMT and AMT did not showed differences. Correlations were showed between all handgrip tests and elbow flexor force for AMT, and between DPD and elbow extensor, abductor, adductor and extensor of shoulder for n-AMT. influences to the performance of the force dynamometry. It could be concluded that handgrip force and dynamic strength of upper limbs did not were putative responses for bull riding practice.

Perfil antropométrico e força de membros superiores em competidores de montaria em touros

A força de preensão manual tem sido relatada como determinante no desempenho de empunhadura em modalidades como lutas e escalada. Este estudo teve por propósito avaliar a aptidão de força isotônica máxima e de preensão manual em praticantes e não praticantes de montaria em touros, a fim de obter parâmetros de referência desta população. Foram avaliados 20 sujeitos em dois grupos, sendo 10 classificados como atletas de montaria e 10 não-atletas. A avaliação da força de preensão manual foi realizada em dinamômetro em posição convencional (DP) e específica (DE), com ambas as mãos (D e E). A força isotônica máxima foi determinada pelo teste de uma repetição máxima (1RM) e também foram obtidas medidas de circunferência dos segmentos, bem como a composição corporal por protocolo de dobras cutâneas. Os valores das variáveis foram comparados pelo teste-t (ρ ≤ 0,05) para dados independentes. As relações entre os valores de força e características antropométricas foram traçadas pelo coeficiente de Pearson. Os resultados para AMT em DPD (43.8±6.8 kgf), DPE (39.4±7.7 kgf), DED (44.9±5.6 kgf) e DEE (39.8±8.3 kgf) comparados aos apresentados por n-AMT em DPD (47.0±3.0 kgf), DPE (42.2±6.1 kgf), DED (49.2±1.5 kgf) e DEE (46.2±4.1 kgf) apresentaram diferenças apenas para DED e DEE. A força nos testes de 1RM (supino reto: 73.2±12.0 kg e 82.0±12.0 kg; rosca direta: 45.2±8.9 kg e 43.8±8.9 kg; tríceps pulley: 67.0±6.3 kg e 72.0±6.3 kg; e puxada posterior: 73.5±8.5 kg e 73.7±7.5 kg) não mostram diferenças entre os grupos. A influência sobre a dinamometria apresenta-se diferente entre os grupos, sendo relevante a força de flexão do cotovelo em AMT e a antropometria e força isotônica para n-AMT. Conclui-se que as características morfo-funcionais de membros superiores não demandam especificidade à montaria em touros.

Anthropometric profile and upper-limbs strength of bull rider s competitors

A força de preensão manual tem sido relatada como determinante no desempenho de empunhadura em modalidades como lutas e escalada. Este estudo teve por propósito avaliar a aptidão de força isotônica máxima e de preensão manual em praticantes e não praticantes de montaria em touros, a fim de obter parâmetros de referência desta população. Foram avaliados 20 sujeitos em dois grupos, sendo 10 classificados como atletas de montaria e 10 não-atletas. A avaliação da força de preensão manual foi realizada em dinamômetro em posição convencional (DP) e específica (DE), com ambas as mãos (D e E). A força isotônica máxima foi determinada pelo teste de uma repetição máxima (1RM) e também foram obtidas medidas de circunferência dos segmentos, bem como a composição corporal por protocolo de dobras cutâneas. Os valores das variáveis foram comparados pelo teste-t (ρ ≤ 0,05) para dados independentes. As relações entre os valores de força e características antropométricas foram traçadas pelo coeficiente de Pearson. Os resultados para AMT em DPD (43.8±6.8 kgf), DPE (39.4±7.7 kgf), DED (44.9±5.6 kgf) e DEE (39.8±8.3 kgf) comparados aos apresentados por n-AMT em DPD (47.0±3.0 kgf), DPE (42.2±6.1 kgf), DED (49.2±1.5 kgf) e DEE (46.2±4.1 kgf) apresentaram diferenças apenas para DED e DEE. A força nos testes de 1RM (supino reto: 73.2±12.0 kg e 82.0±12.0 kg; rosca direta: 45.2±8.9 kg e 43.8±8.9 kg; tríceps pulley: 67.0±6.3 kg e 72.0±6.3 kg; e puxada posterior: 73.5±8.5 kg e 73.7±7.5 kg) não mostram diferenças entre os grupos. A influência sobre a dinamometria apresenta-se diferente entre os grupos, sendo relevante a força de flexão do cotovelo em AMT e a antropometria e força isotônica para n-AMT. Conclui-se que as características morfo-funcionais de membros superiores não demandam especificidade à montaria em touros.