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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Physical Exercise Alleviates ADHD Symptoms: Regional Deficits and Development Trajectory

Archer, Trevor, Kostrzewa, Richard M. 01 February 2012 (has links)
The heterogeneous, chronic, and proliferating aspect of attention deficit hyperactivity disorder (ADHD) and comorbidities covers heritability, cognitive, emotional, motor, and everyday behavioral domains that place individuals presenting the condition at some considerable disadvantage. Disruption of "typical developmental trajectories" in the manifestation of gene-environment interactive predispositions implies that ADHD children and adolescents may continue to perform at defective levels as adults with regard to academic achievement, occupational enterprises, and interpersonal relationships, despite the promise of pharmacotherapeutic treatments. Physical exercise provides a plethora of beneficial effects against stress, anxiety, depression, negative affect and behavior, poor impulse control, and compulsive behavior concomitant with improved executive functioning, working memory and positive affect, as well as improved conditions for relatives and care-givers. Brain-derived neurotrophic factor, an essential element in normal brain development that promotes health-associated behaviors and quality-of-life, though reduced in ADHD, is increased markedly by the intervention of regular physical exercise. Functional, regional, and biomarker deficits, as well as hypothalamic-pituitary-adrenal disruptions, have been improved through regular and carefully applied exercise programs. In view of the complications involving ADHD with co-morbidities, such as obesity, the influence of regular physical exercise has not been found negligible. Physical exercise bestows a propensity for eventual manifestation of "redifferentiated" developmental trajectories that may equip ADHD adults with a prognosis that is more adaptive functionally, independent of the applications of other therapeutic agents and treatments.
182

Examination of the Effect of Physical Exercise on Metabolic Control in Type I Insulin-Dependent Youth with Diabetes Mellitus

Brazzi, Gayle Ann 01 May 1981 (has links)
There is evidence for the importance of physical exercise balanced with diet and insulin therapy in the treatment and control of Type I insulin-dependent diabetes mellitus. Recent attention in the literature has focused on the once neglected component of treatment--exercise. A well-controlled exercise state is generally believed to be beneficial for the individual with diabetes. Limited studies are available on the effect of exercise on long-term metabolic control. Before exercise levels can be professionally prescribed for a given population of youth with diabetes, current exercise patterns should be evaluated as to the effect on long-term metabolic control. It is the purpose of this study to examine the effects of exercise balanced with diet and insulin therapy on long-term metabolic control measured by total glycosylated hemoglobin values. The 26 subjects in the study were all Type I insulin-dependent youth with diabetes mellitus. The subjects ranged from 8 to 17 years of age. Sixteen subjects were female and 10 were male. All subjects were Diabetic Clinic outpatients of Primary Children Medical Center located in Salt Lake City, Utah. The research design utilized both descriptive design and statistical analysis. Questionnaries were used by the researcher to collect the data. Described were demographic data, nutrient intake, clinic staff assessment of metabolic control and growth parameters. Statistical analysis using a one-way analysis of variance test was performed to determine relationships between the dependent variable, total glycosylated hemoglobin, and the independent variables--exercise levels, caloric adequacy, insulin dosage administration, and metabolic control assessment. Further statistical tests were completed utilizing the least significant difference test. Among the described data, nutrient intake and growth parameters were compared to standards of a normal non-diabetic population. The nutrient intake of the subjects was well below the standard for iron. Iron was predominantly below the Recommended Dietary Allowance for iron. The growth parameters of the subjects were fairly equally distributed when compared to a normal population. The females showed some growth retardation with four of 16 females (25 percent) falling at or below the 5th percentile for either height or weight. It was found that a majority (88 percent) of the Type I insulin-dependent youth sampled were participating in regular exercise. Further examination of the subjects' exercise patterns demonstrated an influence of exercise on long-term metabolic control. Statistical significance at the 10 percent level was found between the three exercise levels and total glycosylated hemoglobin values. Individuals participating in predominantly moderately heavy activity (7.0-8.0 METS) had the highest degree of metabolic control. The results of the study support the conclusion that physical exercise has an important effect in the long-term metabolic control of youth with Type I insulin-dependent diabetes. A highly statistical significance was found between the clinic staff metabolic control assessment and total glycosylated hemoglobin values. Statistical significance was not found among the other two treatments. Caloric adequacy data failed to show statistical significance with total glycosylated hemoglobin. Insulin dosage administration data also failed to demonstrate a statistical significance with glycosylated hemoglobin.
183

The Effect of a Physical Conditioning Program on Physical Fitness and Health Locus of Control Among Adolescent Substance Abusers

Owen, Guy Madison 05 1900 (has links)
The purpose of this investigation focused on determining the effects of a physical conditioning program on physical fitness and health attitudes on inpatient adolescent male substance abusers during and following participation in a six week fitness program. The fitness measures chosen for this study were the 1 1/2 mile run, skinfold, sit-and-reach, and grip strength. The first four of these measures make up the AAHPERD test battery (AAHPERD, 1980). The Health Attribution Test (Lawlis and Lawlis, 1980) was administered to determine health locus of control.
184

Fysisk träning reducerar ångest : En litteraturstudie / Physical exercise reduce anxiety : A litterature study

Kumlin Lundmark, Anna, Byhmer, Linda January 2021 (has links)
Bakgrund: Ångestsyndrom är vanligt bland befolkningen i Europa och prevalensen ökar. Lidandet för den drabbade individen och belastningen på samhällsekonomin är påtaglig. Fysisk inaktivitet är en av flera riskfaktorer till ångest, vilket innebär att fysisk träning kan vara ett kostnadseffektivt behandlingsalternativ med låg risk för biverkningar. Syfte: Syftet med litteraturstudien var att undersöka effekten av fysisk träning för att minska ångest. Metod: Litteraturstudien innefattar åtta kvantitativa studier som granskades, analyserades och sammanställdes. Sökningar genomfördes i fyra databaser och valda artiklar kvalitetsgranskades. Samtliga studier har använt beprövade mätinstrument för ångest och mätningar gjordes pre-intervention, under intervention samt post- intervention. Resultat: Fysisk träning ger ångestreducerande effekt. Samtliga studier visade en signifikant förändring av ångest från baslinje till slut och fem studier visade även en signifikant förändring för fysisk träning jämfört med en kontrollgrupp. Konklusion: Fysisk träning är en effektiv behandling för personer med ångest och hög ångestkänslighet utan större risk för biverkningar, det är kostnadseffektivt och har flera fördelar då fysisk träning även leder till bättre hälsa. / Background: Anxiety disorders are common among the European population and the proportion of affected increase. The affected individual is suffering, and the economic burden in the society is great. Physical inactivity is a risk factor for anxiety indicating that exercise is a cost-efficient treatment with low risk of side effects. Aim: The aim of this study was to examine the effect of physical exercise to reduce anxiety. Methods: This literature study contains eight quantitative studies that have been reviewed, analyzed and compiled. Searches were made in four databases and the studies were quality analyzed. All of these studies have used well known instruments to measure anxiety. Measures have been made pre-intervention, during intervention and post-intervention. Results: Physical exercise leads to an anxiety reduction. All of the studies showed a significant change in anxiety from baseline to post-intervention and five studies also showed a significant change for physical exercise in comparison to a control group. Conclusion: Physical exercise is an effective treatment for those suffering from anxiety and anxiety sensitivity with a low risk of side effects, it is cost-efficient and have many benefits due to the fact that physical exercise also leads to a better health.
185

Exercise, visuospatial rotation performance and life satisfaction : A study of correlations between physical activity and some presumed benefits

Lilja, Claes January 2017 (has links)
SourceURL:file://localhost/Users/ClaesAct/Dropbox/LNU%20psykologi/Uppsats/Examensarbete_ClaesLilja_HT16_2PS600.doc Physical exercise has been associated with various health benefits, including improved cognitive functioning, well-being and life satisfaction. Other variables that have been found to explain these areas include gender, age, dispositional optimism, meditation practice, and videogame habits. The aim of the present study was to explore whether physical exercise on its own has benefits for visuospatial rotation abilities and life satisfaction. It was also the intention to examine how other known factors of age, gender, dispositional optimism, meditation, and videogames may help predict visuospatial rotation abilities and satisfaction with life. The results showed no significant explanation for visuospatial performance while finding some exercise measurements and physical activity level to have significant correlations with life satisfaction. Dispositional optimism was found to be the strongest indicator of life satisfaction, while gender was determined to not hold explanatory power for either of the criterion variables.
186

Fitness-Related Alterations in Blood Pressure Control: The Role of the Autonomic Nervous System

Smith, Michael Lamar, 1957- 12 1900 (has links)
Baroreflex function and cardiovascular responses to lower body negative pressure during selective autonomic blockade were evaluated in endurance exercise trained (ET) and untrained (UT) men. Baroreflex function was evaluated using a progressive intravenous infusion of phenylephrine HCL (PE) to a maximum of 0.12 mg/min. Heart rate, arterial blood pressure, cardiac output and forearm blood flow were measured at each infusion rate of PE. The reduction in forearm blood flow and concomitant rise in forearm vascular resistance was the same for each subject group. However, the heart rate decreases per unit increase of systolic or mean blood pressure were significantly (P<.05) less in the ET subjects (0.91 ± 0.30 versus 1.62 ± 0.28 for UT). During progressive lower body negative pressure with no drug intervention, the ET subjects had a significantly (P<.05) greater fall in systolic blood pressure (33.8 ± 4.8 torr versus 16.7 ± 3.9 torr). However, the change in forearm blood flow or resistance was not significantly different between groups. Blockade of parasympathetic receptors with atropine (0.04 mg/kg) eliminated the differences in response to lower body negative pressure. Blockade of cardiac sympathetic receptors with metoprolol (0.02 mg/kg) did not affect the differences observed during the control test. It was concluded that the ET subjects were less effective in regulating blood pressure than the UT subjects, because of 1) an attenuated baroreflex sensitivity, and 2) parasympathetic-mediated depression of cardiac and vasoconstrictive responses to the hypotensive stress.
187

Efektivita tréninku paměťových a tělesných schopností u seniorů / The efficiency of memory and physical training of the elderly

Waidingerová, Iveta January 2011 (has links)
The thesis discusses the training of cognitive functions and physical exercise in the elderly population. It concerns the issue of active ageing, which is a very topical one. The theoretical part describes the findings and results of the latest studies mainly in seniors of good cognitive health. The practical part presents the research in how the seniors of good cognitive health respond to the combination of cognitive training, in other words memory training, and physical exercise. Keywords: ageing, active ageing, cognitive function training, memory training, physical exercise
188

Efeitos modulatórios da PTEN sobre a cognição e a plasticidade sináptica em camundongos submetidos a intervenções não-farmacológicas: a dieta intermitente e o exercício físico. / Modulatory effects over cognition and synaptic plasticity of mice under non-pharmacological interventions: intermittent fasting and physical exercise.

Costa, João Victor Cabral 31 May 2017 (has links)
Inicialmente caracterizada como proteína supressora de tumor, a PTEN (phosphatase and tensin deleted on chromosome 10) tem sido objeto de estudo de trabalhos relacionados a outros processos envolvendo proliferação, sobrevivência e migração celulares, apresentando um potencial papel modulatório na neurogênese e plasticidade sináptica. Fatores ambientais, como a dieta intermitente e o exercício físico, também podem modular estes processos, podendo ser utilizados como intervenções para neuroproteção e melhora de déficits de aprendizado e memória. A ausência de PTEN em neurônios ocasiona anomalias anatômicas e funcionais, culminando em sinaptogênese aumentada e redução do LTP e LTD. Levando-se em consideração a potencial modulação da via PI3K/AKT pela dieta intermitente e pelo exercício físico, a avaliação da influência destas intervenções sobre os efeitos da deleção neuronal da PTEN constitui uma interessante ferramenta de estudo para melhor elucidação dos mecanismos associados à plasticidade sináptica. Este trabalho objetivou caracterizar bioquímica e funcionalmente o hipocampo e o córtex de camundongos adultos com deleção neuronal da PTEN, avaliando seus efeitos sob influência de intervenções não-farmacológicas. Para isto, foram utilizados camundongos com nocaute neuronal condicionado da PTEN (PtenloxP/+;Nse-Cre+). Os animais foram submetidos à dieta intermitente ou exercício físico voluntário por um período de 30 dias, avaliados por ensaios comportamentais (labirinto em cruz elevado, campo aberto, reconhecimento do objeto novo ou da localização do objeto, labirinto aquático de Morris e esquiva inibitória) e, posteriormente, foram realizadas as análises de Western Blotting, da atividade da enzima óxido nítrico sintase (NOS) e dosagem do fator neurotrófico derivado do encéfalo (BDNF). A deleção neuronal da PTEN induziu macrocefalia por aumento da massa cortical. A deleção condicionada da PTEN, sob estímulo de intervenção não-farmacológica dieta intermitente ou exercício físico induz um efeito ansiolítico nos animais, no labirinto em cruz elevado. Os resultados do campo aberto, porém, paradoxalmente não reforçam este resultado. Interessantemente, o isolamento social intrínseco ao estudo do exercício físico induziu um aumento do perfil de ansiedade nos animais, independentemente do genótipo ou tratamento. Os resultados do labirinto aquático de Morris não foram conclusivos, porém apontam para um possível déficit de memória espacial nos animais HT, além de, supreendentemente, um efeito deletério do exercício físico também observado nos níveis corticais de BDNF. Na esquiva inibitória, o déficit dos animais HT foi efetivamente resgatado pela dieta e pelo exercício físico. O hipocampo não apresentou alterações bioquímicas significativas. No córtex, pode-se confirmar a diminuição da expressão da PTEN e possível ativação da AKT, embora nenhum efeito sobre os receptores ionotrópicos glutamatérgicos tenha sido observado. O perfil de expressão da Cre recombinase foi validado por meio da linhagem Nse-Cre+;tdTomato+. O estudo da linhagem PtenloxP/+;Nse-Cre+ demonstrou um interessante potencial para avaliação dos efeitos da PTEN sobre a cognição e a plasticidade sináptica, porém um melhor balizamento dos ensaios faz-se necessário, visando a busca de condições de análise dos efeitos observados. Ainda, a expansão dos estudos com a linhagem por meio da utilização de outros estímulos pode constituir uma interessante forma de revelar os efeitos não observados. / First characterized as a tumor suppressor, PTEN (phosphatase and tensin deleted on chromosome 10) has been a target studied in many projects related to processes involving cell proliferation, survival and migration, showing a potential modulatory role in controlling neurogenesis and synaptic plasticity. Environmental factors, such as intermittent fasting and physical exercise, can also modulate those processes, thus having the potential of being applied as neuroprotective interventions aiming to improve learning and memory deficits. PTEN absence in neurons cause anatomical and functional anomalies, culminating in increased synaptogenesis and LTP and LTD reduction. Considering the potential of intermittent fasting and physical exercise to exert a modulatory role over the PI3K/AKT pathway, the assessment of the influence of these interventions over the effects of PTEN neuronal deletion is of great interest, as it can help better elucidate the mechanisms of synaptic plasticity. This work aimed to functionally and biochemically assess the hippocampus and the cortex of adult mice with a conditioned neuronal deletion of PTEN (PtenloxP/+;Nse-Cre+), evaluating its effects under the influence of non-pharmacological interventions. Animals were submitted to an intermittent fasting or to a voluntary physical exercise protocol for 30 days, then assessed by behavioral (elevated plus maze, open field, novel object or object location recognition tests, Morris water maze, and passive avoidance) and biochemical (Western blotting, nitric oxide synthase activity, BDNF levels) assays. The neuronal PTEN deletion induced macrocephaly through an increase in cortical mass. Also, under the stimuli of non-pharmacological interventions intermittent fasting or physical exercise the deletion induced an anxiolytic effect on the elevated plus maze assay. On the other hand, the open field results were paradoxical. Interestingly, social isolation an intrinsic factor from the physical exercise protocol induced an increase in the anxiety behavior, independently of genotype or treatment. Results from the Morris water maze assay were not conclusive, however they pointed to a likely spatial memory deficit on animals with the PTEN deletion. Surprisingly, a deleterious effect of physical exercise was also observed an effect found on BDNF levels as well. At the passive avoidance test, the deficit from the HT group was effectively rescued by either intermittent fasting and physical exercise. The hippocampus did not show any significant biochemical alterations. However, the decreased PTEN expression was confirmed in the cortex, as well as the possible AKT activation, although any effect over the glutamatergic ionotropic receptor was found. The Cre recombinase expression profile was validated through the reporter lineage Nse-Cre+;tdTomato+. The study of PtenloxP/+;Nse-Cre+ lineage showed great potential of assessing PTEN effects on cognition and synaptic plasticity. However, a deeper standardization of parameters is recommended in order to better evaluate the observed effects. In addition, by expanding the study of this lineage through the application of other stimuli could constitute an interesting way of revealing these non-observed results.
189

Análise da modulação autonômica do coração em repouso e atividade eletromiográfica relacionada à variabilidade da frequência cardíaca durante o exercício dinâmico em cicloergômetro / Analysis of the autonomic modulation of the heart in rest and activity electromyographic related the heart rate variability during dynamic exercise in cicle ergometer

Silva, Cristiano Sales da 22 November 2002 (has links)
A variabilidade da freqüência cardíaca (VFC) tem sido utilizada como um marcador fisiológico do controle autonômico do coração, enquanto a eletromiografia de superfície (EMGs) tem mostrado ser uma ferramenta útil de análise para avaliar a resposta muscular frente ao exercício físico. Assim os objetivos do presente estudo foram: avaliar o controle autonômico do coração a partir das respostas da freqüência cardíaca e de sua variabilidade nas condições de repouso, nas posições supina e sentada, e durante teste de esforço físico dinâmico contínuo do tipo rampa (TEFDC-R). Avaliar a atividade eletromiográfica durante o TEFDC-R e ainda verificar a correlação entre a atividade eletromiográfica e a variabilidade da freqüência cardíaca durante o TEFDC-R. Metodologia: estudou se 10 homens, ativos, saudáveis, jovens (23,7 ± 3,02 anos) em repouso, nas posições supina e sentada, e durante TEFDC-R, com incrementos de 20 Watts (W) por minuto. Os dados de freqüência cardíaca e dos intervalos R-R (ms) foram coletados em tempo real, batimento a batimento, durante o repouso e o exercício. A EMGs integrada foi coletada do músculo vasto lateral (VL) nos 20 segundos finais de cada minuto durante o TEFDC-R. Análise dos dados: foram calculados os valores médios da freqüência cardíaca (FC) em bpm e dos intervalos R-R (iR-R) em ms em repouso durante os 15 minutos e o índice temporal RMSSD dos iR-R (ms) e da FC (bpm) nessas condições. Durante o TEFDC-R, foi obtida a média da FC (bpm) e o RMSSD dos iR-R (ms) nos 20 s finais de cada minuto de exercício paralelamente a análise da EMGs pelo índice RMS da amplitude do sinal em microvolts. Metodologia estatística: Para a análise estatística utilizou-se os testes não paramétricos de Wilcoxon para amostras pareadas, de Friedman para medidas repetidas seguido de técnicas de comparações múltiplas com o teste de Dunn e análise de correlação de Spearman. Foram considerados níveis de significância de á=0,05. Resultados: os dados apresentam significância estatística (p<0,05) nas seguintes análises: 1) menor FC (bpm) e maior iR-R (ms) médios em supino em relação a sentado; 2) maior VFC em supino quando comparado a sentado; 3) FC (bpm) média e RMSSD dos iR-R (ms), durante o TEFDC-R, entre a potência de 4 W e os intervalos a partir de 55 e 60 W; 4) aumento do índice RMS da EMGs entre 4 W e a partir do intervalo de 57 e 60 W; 5) correlação entre RMS e RMSSD (rs=-0,64), entre FC e RMS (rs=0,61) e entre FC (bpm) e RMSSD (rs=-0,76). Conclusões: nossos dados sugerem que houve uma alteração no balanço vago-simpático com predominância vagal na posição supina quando comparada com a sentada. Mostram ainda, uma associação entre o incremento de potências durante o exercício físico com o aumento do recrutamento de fibras musculares com concomitante aumento da freqüência cardíaca e diminuição da VFC. Essa associação é atribuída tanto ao comando de controle central como dos mecanismos reflexos periféricos, ativados a partir das aferências das fibras musculares do grupo III (ergoceptores) e do grupo IV (metaboloreceptores). Sugerindo o trânsito de informações advindos do córtex motor ativando as fibras musculares e paralelamente à área cardiovascular, modulando o sistema nervoso autonômico do coração / Heart rate variability (HRV) has been used as a physiological marker of heart autonomic control, while surface electromyography (SEMG) has shown to be a useful analysis tool for evaluating muscular response to physical exercise. Therefore, the purpose of the present research was to evaluate heart autonomic control beginning from heart rate (HR) answers and its variability (HRV) in rest conditions, in supine and seating positions, and during test of dynamic physical exercise continuous of ramp type (TDPEC-R). We also intended to evaluate electromyographic activity during TDPEC-R and analyze correlation between HRV and SEMG during test of dynamic physical exercise continuous of ramp type (TDPEC-R). Methodology: Ten men; young (23,7 ± 3,02 years), healthy and with an active life style; were followed up during TDPEC-R in rest, supine and seating positions, with 20 W increments per minute. The HR and R-R intervals (R-RI) data were recorded on a beat-to-beat basis in real time during rest and exercise. Integrated SEMG was collected from vastus lateralis muscle captured during the last 20 seconds of each minute during TDPEC-R. Analysis of the data: HR average values were calculated [in beats per minute (bpm)] and R-RI, in rest condition for 15 minutes. RMSSD temporal index of R-RI and HR were calculated in both conditions. During TDPEC-R, the average HR and RMSSD of R-RI was achieved in the last 20 s of each minute of exercise in parallel with SEMG analysis by RMS index of signal width in microvolts. Statistics Methodology: Wilcoxon nonparametric tests were used for paired samples, Friedman’s for repeated measures followed by multiple comparisons techniques with Dunn test and correlation analysis of Spearman. a=0.05 was the considered level of significance. Results: the data presented statistic significance (p<0,05) in the following analyses: 1) lower HR (bpm) and R-RI (ms) average values in supine than in seating position; 2) higher HRV values in supine in comparison to seating position; 3) average HR (bpm) and xiii RMSSD of R-RI (ms) values, during TDPEC-R, between potency of 4 W and intervals starting from 55 and 60 W; 4) increase of RMS index of SEMG between 4 W and starting from interval of 57 and 60 W; 5) correlation between RMS and RMSSD (rs=-0.64), between HR and RMS (rs=0.61) and between HR (bpm) and RMSSD (rs=-0.76). Conclusions: our data suggest that there was an alteration in vagal- sympathetic balance with vagal predominance in supine position in comparison to seating position. The data also demonstrate association between power increment during physical exercise with increase of muscular fibers recruitment with simultaneous HR increase and HRV decrease. This association is attributed to central control command as well as to outlying reflexes mechanisms, activated from afferent muscular fibers of groups III (ergoreceptors) and IV (metaboreceptors). Which suggests information traffic from the motor cortex, activating muscular fibers, and parallel to cardiovascular area, modulating the autonomous nervous system of the heart
190

Estimativa das forças e torques articulares em seres humanos durante o andar em piscina com água rasa / Estimates of joint forces and torques during human walking in pool with shallow water

Orselli, Maria Isabel Veras 19 May 2008 (has links)
O ambiente aquático é um recurso bastante utilizado na prática de atividade física, reabiltação e lazer. No entanto, apesar de seu amplo uso, pouco se sabe sobre a demanda mecânica a que nosso corpo está sujeito durante a atividade física neste ambiente. O conhecimento das cargas sobre o corpo durante exercícios em água poderá permitir uma melhor compreensão das adaptações realizadas pelo ser humano para se movimentar neste ambiente e, ainda, auxiliar na prescrição correta de atividades físicas. O objetivo deste trabalho foi, portanto, estimar as forças e torques articulares sobre o tornozelo, joelho e quadril de adultos jovens, saudáveis, durante o andar em ambiente terrestre e aquático (água rasa). Para tanto, conduzimos um experimento no qual 10 indivíduos caminharam com velocidade auto-selecionada nos dois ambientes. Durante o andar medimos as componentes da força de reação do solo, usando uma plataforma de força, e filmamos os movimentos, com auxílio de um de sistema de aquisição de imagens. As forças e torques internos foram determinadas através da técnica da dinâmica inversa e de estimativas das forças de arrasto e respectivos torques, realizadas a partir da teoria das faixas (\"strip theory\"). Os resultados referentes à cinemática articular e descritiva e às forças de reação do solo foram, no geral, semelhantes aos resultados apresentados em estudos anteriores, indicando que não há mudanças na coordenação dos movimentos articulares nem re- organização temporal da passada durante o andar em água. Entretanto, foi possível perceber mudanças nos sentidos dos torques articulares durante o ciclo para o joelho e o quadril, sugerindo que, para manter a mesma coordenação articular sob a ação do empuxo e do arrasto, é necessário promover mudanças nos padrões dos torques internos nestas articulações. Com relação à articulação do tornozelo, os resultados mostram que há diminuição nos torques articulares necessários para gerar a flexão plantar durante o apoio. A estimativa das forças de arrasto se mostrou adequada para descrever a situação experimental, o que indica que os valores apresentados neste estudo são adequados para descrever a carga mecânica no aparelho locomotor durante o andar em piscina com água rasa. / The aquatic environment is a resource often used for the practice of physical activity, rehabilitation, and leisure. However, despite its extensive use, little is known about the mechanical demand that our body is subjected during physical activity in this environment. The knowledge of the load on the human body during water exercise will give us a greater understanding of the adaptations of the human being in water and assist the health professional to the correct prescription for physical activities. The goal of this work was, therefore, to estimate the internal joint forces and moments on the ankle, knee, and hip joints of young healthy adults during walking in the terrestrial and aquatic (shallow water) environments. For that, we conducted an experiment in which 10 subjects walked with self-selected speed in both environments. During the experiment, we measured the components of ground reaction forces, with a force plate, and recorded the subject\'s movements with a video analysis system. To find the forces and moments we used the inverse dynamics procedure and the calculation of drag forces and moments were based on the strip theory. The results concerning the joints and descriptive kinematics and the ground reaction forces were, in general, similar to the results presented in previous studies, indicating that there aren\'t changes in the coordination of joint movements or a re-organization of the stride during walking in water. Meanwhile, we were able to see changes in the directions of joint moments during the gait cycle for the knee and hip joints, suggesting that to keep the same joint coordination under the action of drag and buoyancy, it is necessary to promote changes in the patterns of internal moments in these joints. As for the ankle, the results showed that there is a decrease in joint moments necessary to generate the plantar flexion during the support phase. The estimation of the drag forces was adequate to describe the experimental situation, which suggests that the values presented here can describe correctly the mechanical load on the locomotor system during walking in shallow water.

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