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Respostas cardiorrespiratórias, neuromuscularese e cinéticas de exercícios de hidroginástica / Cardiorespiratory, neuromuscular and kinetic responses of water aerobic exercisesAlberton, Cristine Lima January 2011 (has links)
O objetivo do presente estudo foi analisar as respostas cardiorrespiratórias, neuromusculares e cinéticas de mulheres realizando exercícios de hidroginástica em diferentes intensidades de esforço. No estudo I, 20 mulheres jovens (24,0 ± 2,5 anos; 163,3 ± 6,7 cm; 60,0 ± 6,7 kg) realizaram quatro sessões de testes progressivos, três correspondentes aos testes aquáticos (corrida estacionária (CE), chute frontal (CF), deslize frontal (DF)) e uma correspondente ao teste em esteira terrestre (EST), com o intuito de determinar e comparar as respostas de frequência cardíaca (FC), consumo de oxigênio ( 2 VO ) e ventilação (Ve ) no primeiro limiar ventilatório (LV1), no segundo limiar ventilatório (LV2) e no máximo esforço (MAX). No estudo II, 15 participantes da amostra realizaram duas sessões, uma no meio aquático (MA) e outra no meio terrestre (MT). O protocolo de testes consistiu na execução dos três exercícios de hidroginástica nas três intensidades pré-determinadas (LV1, LV2 e MAX) com o intuito de determinar o valor de pico da força de reação do solo vertical (Fzpico) e o impulso (IMP). No estudo III, 12 participantes da amostra realizaram uma sessão correspondente ao protocolo experimental, que consistia na execução dos três exercícios de hidroginástica nas três intensidades de esforço previamente avaliadas, com o intuito de determinar as respostas de 2 VO , atividade eletromiográfica (EMG) dos músculos reto femoral (RF), semitendinoso (ST), vasto lateral (VL), porção curta do bíceps femoral (BF), tibial anterior (TA) e gastrocnêmio lateral (GL) e a Fzpico. ANOVA para medidas repetidas de um, dois e três fatores foram utilizadas (α = 0,05). Ao comparar as respostas cardiorrespiratórias entre protocolos de testes progressivos, não foram observadas diferenças significativas entre os exercícios aquáticos para nenhuma das intensidades. No entanto, o protocolo em EST apresentou valores significativamente maiores de FC em todas as intensidades, de 2 VO nas intensidades LV2 e MAX, e de Ve na intensidade LV2. Ao analisar a força de reação do solo, respostas significativamente maiores para Fzpico e IMP foram verificadas para MT comparado a MA. Diferenças significativas foram observadas entre todas as intensidades para Fzpico e IMP no MT, e IMP no MA. Todavia, diferenças significativas foram observadas somente entre LV1 e as demais intensidades para Fzpico no MA. Além disso, no MA, valores de Fzpico significativamente menores foram observados entre o exercício DF e os demais exercícios. Para o sinal EMG, valores significativamente maiores foram observados para CF e menores para CE na atividade de todos os músculos, exceto TA que apresentou maiores respostas para DF comparado aos demais. Além disso, diferenças significativas entre as intensidades foram observadas para todos os grupos musculares. A partir dos resultados, conclui-se que, em um programa de treinamento de hidroginástica, existe a necessidade de realizar-se testes máximos específicos nos exercícios aquáticos, uma vez que as respostas de FC, 2 VO e Ve apresentaram diferenças entre os exercícios de hidroginástica analisados e EST. Outro fator a ser levado em consideração é a escolha da intensidade e dos exercícios a serem prescritos. Se o objetivo for amenizar a ação da Fzpico, exercícios com as características do DF devem ser priorizados, sendo importante salientar que o mesmo apresenta uma intensa atividade neuromuscular para todos os músculos analisados, exceto GL. Além disso, intensidades correspondentes ao LV1 devem ser utilizadas a fim de minimizar a Fzpico, todavia, nessa intensidade a atividade neuromuscular foi significativamente menor para todos os exercícios e músculos analisados. Por outro lado, se o objetivo é trabalhar com altas intensidades, não existe diferença entre a Fzpico correspondente ao esforço máximo e LV2, logo a intensidade máxima pode ser utilizada com a mesma segurança que LV2, apresentando um menor IMP e uma maior ativação EMG para todos os grupos musculares analisados. No entanto, se o objetivo for minimizar a ativação muscular, sugere-se o uso do exercício CE, uma vez que ele pode ser utilizado nas aulas de hidroginástica com a mesma intensidade cardiorrespiratória que os demais exercícios avaliados, induzindo a uma menor fadiga periférica. / The aim of the present study was to analyze the cardiorespiratory, neuromuscular and kinetic responses of women performing water aerobic exercises at different effort intensities. In study I, 20 young women (24.0 ± 2.5 years; 163.3 ± 6.7 cm; 60.0 ± 6.7 kg) performed four progressive test sessions, three corresponding to aquatic tests (stationary running (SR), frontal kick (FK), cross country skiing (CCS)) and one to treadmill (TRE), with the purpose of determining and comparing the heart rate (HR), oxygen uptake ( 2 VO ) and ventilation (Ve ) responses at the first ventilatory threshold (VT1), second ventilatory threshold (VT2) and maximal effort (MAX). In study II, a sample of 15 participants performed two sessions, one in water immersion (WI) and the other on dry land (DL). The test protocol consisted of three water aerobic exercises performed at three pre-determined intensities (VT1, VT2 and MAX) with the purpose of determining the peak vertical ground reaction forces (Fzpeak) and impulse (IMP). In study III, a sample of 12 participants performed one session corresponding to the experimental protocol, which consisted of three water aerobic exercises performed at the three previously evaluated effort intensities, with the purpose of determining the VO2 , electromyographic activity (EMG) of rectus femoris (RF), semitendinosus (ST), vastus lateralis (VL), short head of biceps femoris (BF), tibialis anterior (TA) and gastrocnemius lateralis (GL), and the Fzpeak. One-way, two-way and three-way repeated measures ANOVA were used (α = 0.05). Regarding cardiorespiratory responses to the progressive test protocols, there were no significant differences between aquatic exercises at any intensity. However, the TRE protocol showed significantly higher HR at all intensities, VO2 at intensities corresponding to VT2 and MAX, and Ve at VT2. Analyzing the ground reaction forces, significantly higher values of Fzpeak and IMP were observed for DL compared to WI. It was observed significant difference between all intensities for Fzpeak and IMP on DL, and for IMP in WI. Nevertheless, a difference was observed between VT1 and higher intensities for Fzpeak in WI. In addition, in WI significantly lower Fzpeak values were observed for CCS compared to the other exercises. Regarding the EMG signal, significantly higher muscle activity was found for the FK, and lower for the SR, except in the TA muscle, which presented higher responses for the CCS compared to the other exercises. Moreover, there were significant differences between intensities for all muscle groups. According to the results, it might be concluded that, during water aerobics training is important to perform specific maximal tests in the aquatic exercises, since the HR, VO2 and Ve responses presented differences between water aerobic exercises and TRE. Another important issue that must be considered is the exercise and intensity to be prescribed. Exercises with similar characteristics to the CCS must be priorized if the aim is to attenuate the Fzpeak action, as it is important to highlight that this exercise presents intense neuromuscular activity in all the analyzed muscles, with the exception of GL. In order to minimize the Fzpeak, intensities corresponding to VT1 must be performed. However, the neuromuscular activity was significantly lower for all exercises and muscles analyzed at VT1. On the other hand, there is no difference in the Fzpeak between MAX and VT2; thus the maximal intensity is as safe to use as the VT2, with lower IMP and higher EMG activation in all the analyzed muscle groups. Notwithstanding, if the aim is to minimize the muscular activation, SR is recommended since it can be used during water aerobics with a similar cardiorespiratory intensity to the other evaluated exercises, while inducing lower peripherical fatigue.
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Respostas cardiorrespiratórias, neuromuscularese e cinéticas de exercícios de hidroginástica / Cardiorespiratory, neuromuscular and kinetic responses of water aerobic exercisesAlberton, Cristine Lima January 2011 (has links)
O objetivo do presente estudo foi analisar as respostas cardiorrespiratórias, neuromusculares e cinéticas de mulheres realizando exercícios de hidroginástica em diferentes intensidades de esforço. No estudo I, 20 mulheres jovens (24,0 ± 2,5 anos; 163,3 ± 6,7 cm; 60,0 ± 6,7 kg) realizaram quatro sessões de testes progressivos, três correspondentes aos testes aquáticos (corrida estacionária (CE), chute frontal (CF), deslize frontal (DF)) e uma correspondente ao teste em esteira terrestre (EST), com o intuito de determinar e comparar as respostas de frequência cardíaca (FC), consumo de oxigênio ( 2 VO ) e ventilação (Ve ) no primeiro limiar ventilatório (LV1), no segundo limiar ventilatório (LV2) e no máximo esforço (MAX). No estudo II, 15 participantes da amostra realizaram duas sessões, uma no meio aquático (MA) e outra no meio terrestre (MT). O protocolo de testes consistiu na execução dos três exercícios de hidroginástica nas três intensidades pré-determinadas (LV1, LV2 e MAX) com o intuito de determinar o valor de pico da força de reação do solo vertical (Fzpico) e o impulso (IMP). No estudo III, 12 participantes da amostra realizaram uma sessão correspondente ao protocolo experimental, que consistia na execução dos três exercícios de hidroginástica nas três intensidades de esforço previamente avaliadas, com o intuito de determinar as respostas de 2 VO , atividade eletromiográfica (EMG) dos músculos reto femoral (RF), semitendinoso (ST), vasto lateral (VL), porção curta do bíceps femoral (BF), tibial anterior (TA) e gastrocnêmio lateral (GL) e a Fzpico. ANOVA para medidas repetidas de um, dois e três fatores foram utilizadas (α = 0,05). Ao comparar as respostas cardiorrespiratórias entre protocolos de testes progressivos, não foram observadas diferenças significativas entre os exercícios aquáticos para nenhuma das intensidades. No entanto, o protocolo em EST apresentou valores significativamente maiores de FC em todas as intensidades, de 2 VO nas intensidades LV2 e MAX, e de Ve na intensidade LV2. Ao analisar a força de reação do solo, respostas significativamente maiores para Fzpico e IMP foram verificadas para MT comparado a MA. Diferenças significativas foram observadas entre todas as intensidades para Fzpico e IMP no MT, e IMP no MA. Todavia, diferenças significativas foram observadas somente entre LV1 e as demais intensidades para Fzpico no MA. Além disso, no MA, valores de Fzpico significativamente menores foram observados entre o exercício DF e os demais exercícios. Para o sinal EMG, valores significativamente maiores foram observados para CF e menores para CE na atividade de todos os músculos, exceto TA que apresentou maiores respostas para DF comparado aos demais. Além disso, diferenças significativas entre as intensidades foram observadas para todos os grupos musculares. A partir dos resultados, conclui-se que, em um programa de treinamento de hidroginástica, existe a necessidade de realizar-se testes máximos específicos nos exercícios aquáticos, uma vez que as respostas de FC, 2 VO e Ve apresentaram diferenças entre os exercícios de hidroginástica analisados e EST. Outro fator a ser levado em consideração é a escolha da intensidade e dos exercícios a serem prescritos. Se o objetivo for amenizar a ação da Fzpico, exercícios com as características do DF devem ser priorizados, sendo importante salientar que o mesmo apresenta uma intensa atividade neuromuscular para todos os músculos analisados, exceto GL. Além disso, intensidades correspondentes ao LV1 devem ser utilizadas a fim de minimizar a Fzpico, todavia, nessa intensidade a atividade neuromuscular foi significativamente menor para todos os exercícios e músculos analisados. Por outro lado, se o objetivo é trabalhar com altas intensidades, não existe diferença entre a Fzpico correspondente ao esforço máximo e LV2, logo a intensidade máxima pode ser utilizada com a mesma segurança que LV2, apresentando um menor IMP e uma maior ativação EMG para todos os grupos musculares analisados. No entanto, se o objetivo for minimizar a ativação muscular, sugere-se o uso do exercício CE, uma vez que ele pode ser utilizado nas aulas de hidroginástica com a mesma intensidade cardiorrespiratória que os demais exercícios avaliados, induzindo a uma menor fadiga periférica. / The aim of the present study was to analyze the cardiorespiratory, neuromuscular and kinetic responses of women performing water aerobic exercises at different effort intensities. In study I, 20 young women (24.0 ± 2.5 years; 163.3 ± 6.7 cm; 60.0 ± 6.7 kg) performed four progressive test sessions, three corresponding to aquatic tests (stationary running (SR), frontal kick (FK), cross country skiing (CCS)) and one to treadmill (TRE), with the purpose of determining and comparing the heart rate (HR), oxygen uptake ( 2 VO ) and ventilation (Ve ) responses at the first ventilatory threshold (VT1), second ventilatory threshold (VT2) and maximal effort (MAX). In study II, a sample of 15 participants performed two sessions, one in water immersion (WI) and the other on dry land (DL). The test protocol consisted of three water aerobic exercises performed at three pre-determined intensities (VT1, VT2 and MAX) with the purpose of determining the peak vertical ground reaction forces (Fzpeak) and impulse (IMP). In study III, a sample of 12 participants performed one session corresponding to the experimental protocol, which consisted of three water aerobic exercises performed at the three previously evaluated effort intensities, with the purpose of determining the VO2 , electromyographic activity (EMG) of rectus femoris (RF), semitendinosus (ST), vastus lateralis (VL), short head of biceps femoris (BF), tibialis anterior (TA) and gastrocnemius lateralis (GL), and the Fzpeak. One-way, two-way and three-way repeated measures ANOVA were used (α = 0.05). Regarding cardiorespiratory responses to the progressive test protocols, there were no significant differences between aquatic exercises at any intensity. However, the TRE protocol showed significantly higher HR at all intensities, VO2 at intensities corresponding to VT2 and MAX, and Ve at VT2. Analyzing the ground reaction forces, significantly higher values of Fzpeak and IMP were observed for DL compared to WI. It was observed significant difference between all intensities for Fzpeak and IMP on DL, and for IMP in WI. Nevertheless, a difference was observed between VT1 and higher intensities for Fzpeak in WI. In addition, in WI significantly lower Fzpeak values were observed for CCS compared to the other exercises. Regarding the EMG signal, significantly higher muscle activity was found for the FK, and lower for the SR, except in the TA muscle, which presented higher responses for the CCS compared to the other exercises. Moreover, there were significant differences between intensities for all muscle groups. According to the results, it might be concluded that, during water aerobics training is important to perform specific maximal tests in the aquatic exercises, since the HR, VO2 and Ve responses presented differences between water aerobic exercises and TRE. Another important issue that must be considered is the exercise and intensity to be prescribed. Exercises with similar characteristics to the CCS must be priorized if the aim is to attenuate the Fzpeak action, as it is important to highlight that this exercise presents intense neuromuscular activity in all the analyzed muscles, with the exception of GL. In order to minimize the Fzpeak, intensities corresponding to VT1 must be performed. However, the neuromuscular activity was significantly lower for all exercises and muscles analyzed at VT1. On the other hand, there is no difference in the Fzpeak between MAX and VT2; thus the maximal intensity is as safe to use as the VT2, with lower IMP and higher EMG activation in all the analyzed muscle groups. Notwithstanding, if the aim is to minimize the muscular activation, SR is recommended since it can be used during water aerobics with a similar cardiorespiratory intensity to the other evaluated exercises, while inducing lower peripherical fatigue.
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An Analysis of Infant Bouncing at Different Spring FrequenciesHabib Perez, Olinda D January 2011 (has links)
Infants explore environments through repetitive movements which are constrained or facilitated by the environmental context. The current studies analyzed how typically developing infants bounced in four environments that differed by system natural frequency. Four pre-walking infants (age 9.7 months ±1.8) were placed in four spring conditions with natural spring frequencies of 0.9, 1.15, 1.27 and 1.56 Hz. All infants bounced above the natural spring frequency in all conditions suggesting that they do not solely behave like a mass-spring system. Two patterns of bouncing adaptations were identified. Three infants regulated bounce frequency, while one infant regulated the percentage of time on the ground. When infants matched their bounce frequency to the natural frequency, trunk vertical displacement and joint ranges of motion decreased across conditions and demonstrated a shift from non-spring like to circular spring-like phase planes. Moderate to high correlations were found for inter- and intra-limb coordination. Conversely, when an infant regulated time on the ground, trunk vertical displacement and joint ranges of motion remained the same across conditions and inter- and intra-limb correlations were low to moderate. Phase planes remained circular spring-like for this infant. Asymmetrical loading patterns and decreasing vertical ground reaction forces were found in all infants suggesting that a timing component is always regulated. The difference in bouncing pattern may be indicative of different bouncing skill level.
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Susceptibility to Ankle Sprain Injury between Dominant and Non-Dominant Leg During Jump LandingsPashak, Riley 01 January 2019 (has links)
Ankle sprains are one of the most common injuries within athletics in the United States with approximately one-million student athletes experiencing ankle sprains each year. Studies argue excessive or rapid ankle inversion occurring from jump landings may cause ankle sprains. Also, the effect of limb dominance on risk of ankle sprain is not well documented.
The aim of this study was to determine if there is an affect of leg dominance on landing mechanism of the ankle joint that predisposes either ankle joint to greater risk of ankle sprain.
Twelve recreationally active subjects were recruited and completed four maximal vertical jumps. Ground reaction force, marker position data and maximal vertical jump height were collected using two Bertec Force plates, a 10-camera motion capture system, and a Vertec Vertical Jump Trainer, respectively. Cortex and Visual3D software programs were used to process the motion capture data and to calculate peak vertical ground reaction forces(vGRF), loading rate, and ankle joint moments. There were no statistically significant differences in ankle joint moment or loading rate between limbs, but peak vGRF were significantly higher (p < 0.05) in the non-dominant ankle. The results suggest the non-dominant ankle displays higher injury potential, as the non-dominant leg accumulates a larger peak landing force.
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Determination of Ability to Egress and Ingress Based on Hospital Bed HeightUsmani, Ahmad Raza January 2022 (has links)
No description available.
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The Effect of Arm Swing and Asymmetric Walking on Gait Kinetics in Young AdultsBisson, Nicholas 22 September 2023 (has links)
Introduction: Asymmetric gait is prevalent among older adults as well as in people with gait pathologies (e.g., Parkinson’s disease, following a stroke) and has been linked to a higher risk of falls. While a certain level of gait asymmetry is present in healthy young adults, the simulation of larger asymmetry in this population provides information about efficient strategies to regulate dynamic stability. Research investigating gait asymmetry has described spatiotemporal and kinematic strategies. However, limited information is available regarding changes in gait kinetics.
Research objectives: This thesis aims to determine the gait control strategies utilized by young adults to regulate simulated gait asymmetry combined with different arm movement amplitude. We hypothesized that the hip joint would be the most affected by different arm swing conditions and asymmetric gait. We also hypothesized that asymmetric gait and active arm swing would lead to increased variability in the lower-limb movements.
Methods: Fifteen healthy young adults (23.4±2.8 years, 7 Females) walked with three arm swing conditions (held, normal, and active) during symmetric and asymmetric walking conditions. The CAREN-extended System (Motek Medical, Amsterdam, NL) was used for data collection. Outcome measures included step length and width mean and variability (meanSD), vertical ground reaction forces, and lower-limb joint moment impulse mean and variability (meanSD) in the sagittal and frontal planes.
Results: When comparing arm swing conditions, the active arm swing led to an increase in step width variability, vertical ground reaction forces, hip and knee variability in the sagittal plane, ankle abduction moment for the fast leg, as well as in knee variability in the frontal plane. As for gait symmetry, the asymmetric condition led to increased step width for the fast and slow legs and increased vertical ground reaction forces for the slow leg. The asymmetric condition further prompted adjustments in the frontal and sagittal planes, particularly at the ankle and hip joints during the braking phase, and in the knee joint during the propulsion phase phases when compared to the symmetric walking condition.
Conclusion: Findings suggest that participants increased hip activity to control the effect of arm motion on the trunk to minimize adaptations in the lower-limb joints. The asymmetry condition demonstrated that participants searched for flexible lower-limb strategies aimed at minimizing bilateral differences between the fast and slow legs during asymmetric walking.
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Vertical ground reaction force estimation using position data measured from a markerless motion capture systemScalley, Timothy Brian 31 August 2012 (has links)
No description available.
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The influence of variations in shoe midsole density on the impact force and kinematics of landing in female volleyball playersNolan, Karen J. 25 May 2004 (has links)
No description available.
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Towards Sparse IMU Sensor-Based Estimation of Walking Kinematics, Joint Moments, and Ground Reaction Forces in Multiple Locomotion Modes via Deep LearningHossain, Md Sanzid Bin 01 January 2024 (has links) (PDF)
Acquiring joint kinematics, joint moments, and ground reaction forces (GRFs) during walking is essential for assessing disease progression and health monitoring during rehabilitation. However, spatial and temporal constraints, expert processing, and high costs limit the current gold standard methods, such as optical motion capture systems and floor-embedded force plates. Experts have suggested wearables with machine learning methods to address this issue, but their large sensor count renders them impractical for daily use, and the use of generic algorithms limits their accuracy. As a result, learning kinematics and kinetics in everyday life outside of laboratory settings is challenging. Thus, there is a need for an inexpensive, near-real-time system and an accurate method for estimating kinematics, joint moments, and GRFs. This dissertation proposes using shoe-mounted IMU sensors and deep learning to estimate these parameters across various locomotion modes, reflecting everyday walking conditions. Four different approaches are explored. The first approach uses shoe-embedded IMU sensors with novel deep learning models, DeepBBWAE-Net, Kinetics-FM-DLR-Ensemble-Net, and DL-Kinetics-FM-Net, which outperform state-of-the-art models but are computationally expensive. The second approach introduces Kinematics-Net and Kinetics-MMF-Net, which are lightweight yet maintain similar performance. Sparse IMU sensors on the feet may miss critical walking dynamics, so the third approach proposes a sensor distillation technique, transferring knowledge from a teacher model (trained with full sensors) to a student model (trained with sparse IMUs), enhancing estimation accuracy. Although our models are trained on a substantial number of subjects, deep learning models tend to perform better with larger datasets. Collecting extensive subject data is resource-intensive and time-consuming. Additionally, public datasets often differ in sensor types, locations, and protocols. Our fourth approach addresses this by proposing a domain adaptation technique that transfers knowledge from source datasets to the target dataset, improving performance in the target domain.
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Análise cinética do soco no karatê em postura natural e avançada / Kinetic analysis of the karate punch in natural stance and advancedViero, Fernanda Todeschini 12 December 2011 (has links)
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Previous issue date: 2011-12-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The main objective of this study was to analyze the kinetic characteristics of the punch in karate in natural stance and advanced where the proposed specific objectives were to verify the strength values (component orthogonal to the fixed target) generated by karate straight punch during the impact on fixed target; measuring ground reaction forces in three orthogonal directions: vertical (z), antero-posterior (y) and medio-lateral (x); compare the peak force of the punch normalized by body weight between the natural posture and stance; and compare the percentage of body weight at the time of peak force of the punch between the natural posture and stance. The study included nine practitioners of Traditional Shotokan Karate, male, graduated from the first dan, and over the age of eighteen years, all invited to participate voluntarily in the study. For the collection of ground reaction forces were used two force platforms AMTI model OR6-GT and the analysis of the punch device was developed with a fixed target instrumented. Data collection was divided into two stages, the first was rated the straight punch in front stance and the second was evaluated in a natural posture. We collected data from participants, the anthropometric characteristics taken after heating the same individual adjusted to the pre-determined position, on the force platforms in front of the column, where your equipment with the target fixed for the execution of instrumented punches average level. The kinetic parameters analyzed were interpreted with the aid of a software routine in scilab-5.3.3 (INRA, France). To present the data we used descriptive statistics. Additionally, we used the paired t-test for detecting differences in performance parameters between the punch and natural stance. All tests were carried out using SPSS 17.0 software (SPSS, USA) at a significance level of 5%. The results showed that the absolute values of impact found in this independent study confirm the stance taken karate as the art of teaching the final blow. In terms of ground reaction forces in three orthogonal directions (z, y, x), results were obtained with the forces in the orthogonal directions z and y, being that on the other hand for ortogonal direction x, the same one was rejected ahead of the necessity for a more accurate analysis. As for comparisons were obtained significant results (p <0.05) for the intensities of punches between the advanced and natural postures and non-significant results (p> 0.05) for the percentage weights at the moment of peak force between the punch advanced postures and natural. Finally, it was stressed that it seems the hip rotation is so important in the efficiency of the blow given that you can make a relationship between the intensity obtained from the impact of the blow and magnitude of the binary system generated by the actions of the feet. / O principal objetivo deste estudo foi analisar as características cinéticas do soco no Karatê em postura natural e avançada onde os objetivos específicos propostos foram verificar os valores de força (componente ortogonal ao alvo fixo) gerados pelo soco direto do karatê durante o impacto no alvo fixo; medir forças de reação do solo nas três direções ortogonais: vertical (z), ântero-posterior (y) e médio lateral (x); comparar o pico de força do soco normalizado pelo peso corporal entre a postura natural e a postura avançada; e comparar o percentual do peso corporal no momento de pico de força do soco entre a postura natural e a postura avançada. Participaram deste estudo nove praticantes de Karatê Shotokan Tradicional, do sexo masculino, graduados a partir do 1o dan, e com idade superior a dezoito anos, todos convidados a participar voluntariamente do estudo. Para as coletas das forças de reação do solo foram utilizadas duas plataformas de força AMTI modelo OR6-GT e para a análise do soco foi desenvolvido um dispositivo com o alvo fixo instrumentado. A coleta de dados foi dividida em duas etapas, na primeira foi avaliado o soco direto na postura avançada e na segunda foi avaliado na postura natural. Foram coletados os dados dos participantes, tomadas as características antropométricas e após aquecimento individual, o mesmo ajustou-se à posição pré-estabelecida nas plataformas de força em frente à coluna, onde se encontrava o aparato com o alvo fixo instrumentado para a execução dos socos a nível médio. Os parâmetros cinéticos analisados foram interpretados com auxílio de uma rotina no software Scilab-5.3.3 (INRA, França). Para apresentar os dados foi utilizada a estatística descritiva. Adicionalmente, foi utilizado o teste t pareado para verificar diferenças nos parâmetros da execução do soco entre a postura avançada e natural. Todos os testes foram realizados com auxílio do software SPSS 17.0 (SPSS, EUA) a um nível de significância de 5%. Pelos resultados verificou-se que para os valores absolutos de impacto encontrados neste estudo independente da postura adotada confirmam o karatê como sendo a arte da doutrina do golpe definitivo. No que tange às forças de reação do solo nas três direções ortogonais (z, y, x), respostas foram obtidas para as forças nas direções ortogonais z e y, sendo que em contrapartida para a direção ortogonal x, a mesma foi desprezada diante da necessidade de uma análise mais acurada. Quanto às comparações se obtiveram resultados significativos (p<0,05) para as intensidades dos socos entre as posturas avançada e natural e resultados não significativos (p>0,05) para os pesos percentuais durante o momento de pico de força do soco entre as posturas avançada e natural. Por fim, destacou-se que ao que parece o giro do quadril tem tanta importância na eficiência do golpe haja vista que se pode fazer uma relação entre a intensidade obtida através do impacto do golpe e magnitude do sistema binário gerado pelas ações dos pés.
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