INTRODUÃÃO. O termo fragilidade à aplicado aos indivÃduos idosos com alto risco para quedas, hospitalizaÃÃo, institucionalizaÃÃo e morte. Embora fragilidade esteja associada a quedas, os mecanismos exatos dessa associaÃÃo ainda nÃo estÃo suficientemente estabelecidos, o que pode limitar as intervenÃÃes nessa Ãrea. A alteraÃÃo da postura poderia ser um fator que nos idosos frÃgeis favoreceria a maior ocorrÃncia de quedas. Sendo assim, abordagens voltadas para a melhoria da postura poderiam ser importantes para a reduÃÃo de quedas em idosos. InvestigaÃÃes sobre a ocorrÃncia de alteraÃÃo da postura em idosos com fragilidade nÃo estÃo disponÃveis. OBJETIVO. Estimar as medidas angulares posturais entre idosos (idade de 60 anos ou mais) frÃgeis, prÃ-frÃgeis e nÃo-frÃgeis residentes em Ãrea urbana de Fortaleza, CearÃ. MÃTODOS. Foram avaliadas medidas angulares posturais, cujas alteraÃÃes implicam em prejuÃzo na dinÃmica corporal e risco de quedas, por meio do software de avaliaÃÃo postural â SAPO. No perÃodo de marÃo de 2009 a outubro de 2010, foram avaliados 158 idosos, na idade de 60 a 92 anos, oriundos de um inquÃrito realizado nos domicÃlios de uma Ãrea urbana da cidade de Fortaleza-CE, distribuÃdos em trÃs categorias: nÃo frÃgeis, prÃ-frÃgeis, e frÃgeis, seguindo os critÃrios de classificaÃÃo proposto no estudo de Fried et al., 2001. A relaÃÃo entre as medidas posturais e presenÃa de fragilidade ajustada para potenciais confundidores, foi estimada por meio de regressÃo logÃstica multivariada. RESULTADOS. Os indicadores posturais: posiÃÃo da cabeÃa anteriorizada (<36 graus), joelho flexum (<172 graus), tornozelo em dorsiflexÃo (<77 graus), pernas tortas (&#8805;185 graus) apresentaram-se significativamente associados à fragilidade depois de ajustados para gÃnero, idade e IMC. CONCLUSÃO. AlteraÃÃes posturais estÃo associadas à fragilidade em idosos. A identificaÃÃo dos indicadores posturais associados à fragilidade pode orientar intervenÃÃes fisioterÃpicas que minimizem os desfechos indesejÃveis, como quedas e reduÃÃo das atividades fÃsicas. / RATIONALE. The term frailty is applied to aged individuals with high risk for falls, hospitalization, institutionalization and death. Frailty is associated with falls, but this association has not yet been sufficiently established, which may limit the intervention in this area. We hypothesized that posture would be a factor that would be associated with the elderly fragile taking it to a higher occurrence of falls in frailty. Approaches focused on improving posture could be important for the reduction of falls in elderly people. Investigations on the occurrence of postural alterations in elderly patients with frailty are not available. OBJECTIVE. This study aimed estimate the postural angular measures among frail, pre-fragile and non-fragile older adults (60 years or more) living in the urban area of Fortaleza, CearÃ. METHODS. Angular postural measures wich alterations are associated with impaired body dynamics and high risk of falls were evaluated. The postural analysis was interpreted by the software of postural evaluation â (software of postural evaluation â SAPO). 158 elderly aging from 62 to 90 years old were evaluated from March 2009 to October 2010 and distributed in three categories: non fragile, pre-fragile, and frail accordingly to classification criteria proposed by Fried et al., 2001. The adjustment for potential confounders relationship between postural measures and presence of frailty was estimated through a multivariate logistic regression. RESULTS. Position of the head protruded (<36 degrees), knee flexed (<172 degrees), ankle dorsiflexion (<77 degrees), legs pies (&#8805;185 degrees) were significantly associated with frailty after being adjusted for gender, age and BMI. CONCLUSION. Posture changes are associated with frailty and the identification of indicators associated with postural fragility can lead to interventions that minimize the undesirable outcomes such as falls and reduction of physical activities and operationalize valuable strategies towards preventive clinical practice.

Asthma cannot be cured, but it can be managed. Asthma management is a public health issue that is complex. Medication, asthma triggers, age, and the environment are all factors that impact asthma management. There is a gap in research in terms of what lifestyle characteristics need to be in place in order for adults to manage asthma. Shaw found that posture care is a lifestyle variable that should be explored as it relates to asthma management in older adults. The Life University Clinic (Marietta, GA) sees asthmatic patients daily and teaches them about a posture care routine through a program called Straighten Up. Based on the health belief model, this study explored how the Straighten Up routine exercises impacted asthma management in adult asthmatic patients with severe asthma (n =304 ). Ordinal regression and logistic regression was used to analyze the relationships between using the Straighten Up posture exercises (independent variable) for 3 months with 3 dependent variables: patients' sleep patterns (night time awakenings due to asthma), use of quick relief medication, and hospitalizations (ER Visits) due to asthma. Straighten Up posture exercises reduced night time sleep interruptions, but not hospitalizations due to asthma or the use of quick relief medications. For persons with asthma, Straighten Up could be an additional tool to manage their asthma and reduce the known impacts of sleep deprivation including accidents, memory loss, and heart disease. For organizations who serve asthmatics, Straighten Up could be an additional resource to share with the population they serve. As a result of this study, Straighten Up exercises are recommended for adult asthmatics with severe asthma as part of their asthma management plan.

No description available.

Thesis (M.Sc. (Human Movement Science))--North-West University, Potchefstroom Campus, 2007.

The aim of this study was to determine the combined effects of high-heeled shoes and load carriage on gait and posture adaptation. Furthermore, the adaptation of gait and posture to the combined two conditions was examined by a comparison of the measured parameters between experienced and novice groups. 30 participants underwent a quantitative measurement of temporospatial, kinematic, and kinetic parameters of hip, knee, and ankle on both loaded and unloaded limbs using 3D motion analysis. Double support time and stride length increased during high-heeled gait and the magnitude of alteration was greater with a load. Increased plantarflexion was main cause of raised heel. Ankle plantarflexor moment increased with high-heeled but decreased with load carriage. As a result, plantarflexor moment diminished, in addition knee extensor moment exaggerated further. Hip extensor moment increased with heel height but not with load weight, however, hip angle was affected only by the load.

The aim of this study was to determine the combined effects of high-heeled shoes and load carriage on gait and posture adaptation. Furthermore, the adaptation of gait and posture to the combined two conditions was examined by a comparison of the measured parameters between experienced and novice groups. 30 participants underwent a quantitative measurement of temporospatial, kinematic, and kinetic parameters of hip, knee, and ankle on both loaded and unloaded limbs using 3D motion analysis. Double support time and stride length increased during high-heeled gait and the magnitude of alteration was greater with a load. Increased plantarflexion was main cause of raised heel. Ankle plantarflexor moment increased with high-heeled but decreased with load carriage. As a result, plantarflexor moment diminished, in addition knee extensor moment exaggerated further. Hip extensor moment increased with heel height but not with load weight, however, hip angle was affected only by the load.

L'impesanteur est un environnement qui induit un stress physiologique aux systèmes circulatoire et respiratoire. En dehors des missions spatiales, les effets physiologiques de l'impesanteur doivent être étudiés par l'entremise de modèles simulant cet environnement. Parmi ces modèles, on compte les vols paraboliques, la position inclinée de -7 degrés tête vers le bas par rapport à l'horizontale et l'immersion dans l'eau jusqu'au cou. Par contre, bien que ces modèles aient été validés, certains d'entre eux présentent des limites importantes. Par exemple, les vols paraboliques sont d'une durée d'environ 25-35 secondes ce qui permet seulement d'étudier les effets de très courte durée de l'impesanteur. L'immersion dans l'eau jusqu'au cou ne tient pas compte du gradient hydrostatique du cou à la tête. La présente étude a pour objectif de comparer la position inclinée de -7 degrés tête vers le bas par rapport à l'horizontale à l'immersion complète dans l'eau. Les variables considérées sont: le volume courant (VC), le débit ventilatoire (VE), l'intervalle RR moyen, le pNN50, le SDNN, les basses fréquences (BF) et hautes fréquences (HF) et l'équilibre sympathovagal (BF/HF). L'hypothèse expérimentale était que la variabilité du rythme cardiaque soit atténuée lors de l'immersion complète dans l'eau par rapport à celle enregistrée en position inclinée -7 degrés par rapport à l'horizontale tête vers le bas. Les résultats de la présente étude démontrent qu'il n'y a pas de différences significatives entre l'immersion complète dans l'eau et la position inclinée de -7 degrés tête vers le bas par rapport à l'horizontale à p < 0,10 lorsque l'on considère les variables énoncées ci-dessus. Ces résultats ont mené au rejet par analyse statistique de l'hypothèse expérimentale ce qui permet de conclure que l'immersion complète dans l'eau induit un stress physiologique équivalent à celui de la position inclinée de -7 degrés tête vers le bas par rapport à l'horizontale. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Immersion dans l'eau, Position inclinée, Variabilité du rythme cardiaque, Arythmie sinusale respiratoire, Impesanteur.

During centrally orchestrated movements, the nervous system must distinguish between appropriate and inappropriate reflexes. I studied local postural flexion reflexes of the crayfish that are evoked by unexpected touch. An isolated abdomen was used which permitted recording and stimulating of tailfan afferents, nerve cord interneurons, and postural motor neurons. Stimulation of the afferents evoked a postural flexion response of the medium tonic and large phasic motor neurons of the superficial flexor nerve; a flexion motor program was then excited by stimulating descending interneurons. Afferent stimulation evoked a smaller motor response during the motor program than before or after. These results indicate that the postural reflex responses to sensory stimulation are inhibited at a site presynaptic to the motor neurons during the flexion motor program. Application of Picrotoxin (blocked inhibition) to the primary afferent-to-mechanosensory interneuron synapse did not prevent the modulation of the postural flexion reflex during the flexion motor program.

Neural mechanisms determining temporal muscle activity patterns during postural control are not well understood. We hypothesize that a feedback control mechanism can predict both temporal extensor muscle EMG and CoM kinematics (acceleration, velocity, and displacement) during postural perturbations before and following peripheral neuropathy to group I afferents induced by pyridoxine intoxication. We introduce a feedback model for analyzing temporal EMG patterns that decomposes recorded electromyogram (EMG) signals into the sum of three center of mass (CoM) feedback components. EMG and CoM kinematics during postural responses due to support surface translations were measured before and 14 days after somatosensory loss in cats. We successfully predicted EMG before and after peripheral neuropathy by modeling a standing cat as an inverted pendulum and decomposing temporal EMG patterns using a simulation with time delayed feedback loop of CoM kinematics. This model accounts for over 60% of the total temporal variability of recorded extensor EMG patterns. Feedback gains for acceleration, velocity and position necessary to predict EMGs before and after sensory loss were different. For intact animals, more that 90% of the initial burst of EMG were due to CoM acceleration feedback, while later portions were due entirely to velocity and position feedback. After peripheral neuropathy, the initial burst was absent and the acceleration gain was significantly reduced when compared to the acceleration gain of intact animals for extensor muscles (p lt 0.05). By successfully decomposing EMG into three kinematic gains, a quantitative comparison of temporal EMG patterns before and after peripheral neuropathy is possible. The reduction of acceleration gain in sensory loss cats suggests that group I afferents provide necessary information that is used as acceleration feedback.

We studied the effects of varying perturbation magnitude and direction on the postural control process of the central nervous system (CNS) caused by perturbation, before and after sensory loss. The electromyogram (EMG) response to a postural perturbation can be composed by a weighted sum of the center of mass (CoM) kinematics. We extended an existing CoM feedback model which predicted EMG of one muscle for unidirectional perturbations; we used recorded data of bidirectional perturbations, which caused muscle activity in anterior as well as posterior muscles. Modeling the CNS as two delayed feedback controllers, we reconstructed the EMGs of two antagonistic muscles simultaneously that were recorded during postural perturbation experiments on cats. Minimizing the error between predicted and recorded EMG and CoM kinematics, we were able to identify controller gains that would result in the best prediction of the recorded EMGs. We hypothesized that the weights on the CoM kinematics remained constant independent of variations in perturbation magnitude or reversed perturbation direction. We applied our model to data from bidirectional perturbations with varying magnitude, with which the cats were perturbed for a short time in one direction and a longer time in the opposite direction. The gains showed small variation for EMG predictions following long perturbations; however, the prediction of EMG following the initial displacement resulted in large gain variations. We showed that these variations were caused by our optimization methods, which was not able to consistently identify controller gains for short initial movements. Using the weights identified for unidirectional perturbations, we were able to predict muscle activity for both directions with the same gains. This suggests that the weights of the CoM kinematics for each muscle did not change for varying perturbation magnitude. We conclude that varying EMG shapes were induced solely by the variation of the CoM kinematics. We repeated the investigations on data that was recorded from cats suffering from sensory loss and found reduced CoM acceleration feedback.