Différents types d'entraînement sont disponibles pour améliorer la qualité de vie des personnes âgées. Cependant, l'entraînement le plus efficace pour améliorer l'équilibre et diminuer le risque de chuter demeure une question actuelle. Il a été démontre qu'un entraînement par biofeedback visuel peut améliorer l'équilibre et la demande attentionnelle des personnes âgées. Et d'après les études avec les patients cardiaques et ceux souffrant d'un traumatisme crânien, un entraînement par réalité virtuelle pourrait être bénéfique pour l'entraînement de l'équilibre chez les personnes âgées. Le but de cette étude était de comparer l'efficacité d'un entraînement d'équilibre dynamique par réalite virtuelle et par biofeedback visuel pour améliorer l'équilibre et la demande attentionnelle des personnes âgées. Au total, 24 personnes âgées en bonne santé ont participé à un programme d'entraînement de 10 semaines à une fréquence de 2 fois par semaine. Les participants s'entraînant par réalité virtuelle (n = 12) devaient jongler avec un ballon virtuel alternant de gauche à droite de façon imprévisible. (Abstract shortened by UMI.)

The purpose of this study was to examine the process of resonance and overall experience of four endurance athletes participating in a 6-week resonance-based intervention. A second objective was to assess the impact of the intervention on the athletes' cycling performance, subjective well-being, and intrinsic motivation. This 16-week study was a multiple case, single-subject design comprising three phases: (1) a 5-week baseline period, (2) a 6-week resonance-based intervention period, and (3) a 5-week post-intervention period. The resonance-based intervention consisted of four in-depth, open-ended, and semi-structured interviews using the Resonance Performance Model (RPM. Newburg et al., 2002) as a framework and daily reflective journalling. The athletes also participated in a follow-up interview 5 weeks following the intervention to discuss whether or not they continued to apply resonance in their life and experienced any benefits from participating in the study. Measures of cycling performance, life satisfaction, positive and negative affect, and intrinsic motivation were taken twice weekly during the three phases of the study. Qualitative results were analyzed deductively based on the components of the RPM, whereas quantitative results were analyzed using the split-middle technique for single-subject designs. Although quantitative analyses provided mixed evidence for the value of the intervention, qualitative results showed that all four endurance athletes perceived that they enhanced their performance, well-being, and intrinsic motivation for both practices and races that occurred during the intervention. They also reported a significant increase in self-awareness, a positive change in focus from outcome to process, and an empowered ability to manage their emotional responses to events. Practical implications for using the RPM with athletes and other populations in exercise and health settings are discussed.

This study investigated whether self-modeling would positively affect intermediate level figure skaters' self-efficacy, state anxiety, motivation, and jump performance more than physical practice alone. Twelve female skaters (M = 13.38 years of age, SD = 1.35) participated in a four week study where they received a self-modeling intervention (SM) for one jump and no modeling (SM-C) for a second jump. They were also compared with a separate control group (CON) of 7 skaters (M = 14.20 years of age, SD = 2.35) who received no intervention for both jumps. Analyses revealed no significant differences between the three conditions. This indicates that while no transfer effects existed between the SM and SM-C conditions, the self-modeling intervention also failed to enhance figure skaters' psychological and physical performance. The athletes' skill level, their perception of the intervention, the characteristics of the task, and the type of self-modeling employed are all discussed as possible explanations for this lack of results. Further empirical examination of self-modeling is recommended to clarify these issues.

The present study aimed to document three athletes' in depth-stories to examine their application of resonance and how it influenced their experience of their sport and life. Each athlete took part in a resonance-based intervention involving seven interviews held approximately every second week, three non-intrusive interviews conducted at the site of competitions, daily reflective journaling, reading a book on resonance (Newburg, 2004), and a post-intervention interview four weeks after the end of the intervention. Two means of analysis were used; deductive categorization and narrative analysis. Two individuals developed and applied their personal process of resonance. As a result, they felt the way they wanted to feel in their endeavors, and enjoyed an increased sense of control and acceptance of themselves and their environment. The three athletes' stories shed light on the importance of reflection and ownership in the process of resonance. This study also sheds light on the role of the facilitator in the intervention.

Lerner, Baker, and Lerner's (1985) Goodness-of-Fit model was adopted as a framework to investigate the influence of varied contexts (football and society) and associated body type ideals on body image. Determining that expectations concerning players' body types existed in the context of football tested the first assumption of the model; both mesomorphic and endomorphic body types were desired. The second assumption was framed by considering that players either match or mismatch the body ideal of each context. Out of 145 participants, 68% matched the expectations of both contexts, 30% mismatched at least one context, and 2% mismatched both contexts. The last assumption maintains that an individual will receive positive feedback if he matches the expectations of a context, resulting in positive psychosocial adjustment, and negative feedback because of a mismatch will result in negative psychosocial adjustment if a mismatch occurs. Our data contradicted the first component of this last assumption; the majority of participants who mismatched one or both contexts reported positive feedback scores (72.3%). The second component was supported, however, as participants who received positive feedback from both contexts generated the highest body image scores (M = 4.08, SD = 0.64) as compared to those who reported negative feedback in one or both contexts (M = 3.61, SD = 0.81, d = 0.69). Unique to this study was questioning the role that valuing the context played. Higher body image scores were observed for participants who valued society, both contexts, or neither context combined compared to participants who valued the sport context alone (M = 4.02, SD = 0.65; M = 3.81, SD = 0.84, respectively). Due to the small effect (d = 0.28), however, value might not add to this model.

Purpose. The primary aim of this thesis was to examine the changes in body heat content (DeltaHb) during exercise. Specifically, Study #1 compared DeltaHb and changes in mean body temperature (DeltaT¯b) and DeltaHb from thermometry with direct calorimetry. Study #2 sought to examine the effect of DeltaH b on different time-responses of measures of body temperature. Methods. Study #1 - Forty-one subjects (23 females) performed 60--90 min of cycling exercise at 40% V˙O2peak. DeltaHb, core, muscle and skin temperatures were measured by direct calorimetry, and DeltaH b was also estimated from conventional thermometry equations. Study #2 - Sixteen subjects (8 females) performed 60 min of cycling exercise at 70 W. Changes in DeltaHb as a function of heat gain and heat loss, core and skin temperatures were measured. Results. Study #1 - Measurements of DeltaHb and DeltaT¯b by direct calorimetry were significantly greater than by conventional thermometry (p < 0.01). Study #2 - Esophageal and tympanic temperatures and whole-body heat loss achieved steady values at a significantly earlier time than rectal temperature (p < 0.01). Conclusions. Study #1 - The calculation of DeltaHb by thermometry underestimates body heat content when compared to direct calorimetry, and estimates of DeltaHb by thermometry, must be revised to a three compartment model that includes muscle temperature. Study #2 - As rectal temperature achieved steady state later than all other measures of temperature and heat flow, it best indicates when whole-body thermal steady-state has been reached.

Le vieillissement s'accompagne généralement d'un déclin des capacités sensorielles. Le présent travail visait donc à déterminer comment la perception tactile des formes est modifiée avec l'âge. Quarante-cinq sujets ont été recrutés et répartis en deux groupes d'âge. Les sujets devaient explorer activement des stimuli de différentes complexités spatiales soit de simples grillages, soit des lettres en relief comme stimulus complexe avec la pulpe de l'index de la main dominante. Pour les formes simples, les sujets devaient répondre si le grillage était orienté verticalement ou horizontalement selon l'axe du doigt. Pour les formes complexes, les sujets devaient identifier la lettre présentée. Les résultats ont montré que le groupe âge exhibait un déclin marqué dans la capacité à discriminer des formes tactilement, et que ce déclin était encore plus marqué dans le cas des formes complexes. Le facteur "âge" constituait la principale source de variance expliquant la performance de discrimination de formes et un impact différentiel de l'âge pour la performance dans les deux tâches a également été révélé. Il existait aussi un lien étroit entre les seuils de résolution spatiale estimés avec des grillages et la capacité à identifier des lettres tactilement. Enfin, des différences qualitatives ont aussi été observées entre les deux groupes dans les patrons d'identification pour la reconnaissance de lettres. Ces données confirment que la perception tactile des formes est grandement affectée par le vieillissement normal et le fait que la discrimination de formes complexes montre un déclin plus important que celle de formes simples suggère que des altérations additionnelles sont présentés au niveau du traitement central de l'information tactile spatiale dans le vieillissement normal.

The purpose of this project was to quantify and analyze the changes that occur to the moments of force and moment powers at the joints of the lower extremity during stair and ramp descent. Methods. A sample population of five male and five female volunteers were asked to walk five times down a 10-degree ramp at normal gait speed, followed by five stair descent trials. Results and discussion. Stair descent has a larger eccentric plantar flexor peak at the ankle joint during weight acceptance. The knee exhibits slightly larger eccentric knee extensor peaks during ramp descent at push - off and there was higher loading of the hip during ramp descent as compared with stair descent. The higher ankle powers at FS during stair descent reveal a concern for those people suffering from ankle pathology and the larger hip and knee peaks during ramp descent is of concern to those with hip and knee problems. These results could be used in the rehabilitative considerations of patients with hip, knee and ankle replacements and as a baseline for future research. (Abstract shortened by UMI.)

Functional knee bracing has been shown to alter lower limb joint mechanics, which may protect the anterior cruciate ligament. Many knee braces have been studied, however, the effects of brace alignment or brace type on lower limb joint mechanics are not known. This study was conducted to determine whether the use of a functional knee brace, the type of brace used or its alignment relative to the knee causes biomechanical or neuromuscular alterations to gait. Ten healthy participants took part in all conditions: walking with a shell and soft shell brace, each aligned according to the manufacturers' specifications; walking with each brace distally misaligned by 1 cm as well as walking without a brace. A motion analysis and force plate system was used to determine the three-dimensional angular impulse, peak joint moments and peak joint angles of the ankle, knee and hip. Electromyographic data were used to support the kinetic data. All data were time normalized to one stride. In addition, kinetic data were normalized to body mass and kinematic data were normalized to the standing position. In comparison to unbraced walking, the shell brace in its aligned position significantly reduced the peak ankle plantarflexor moment. Additionally, there was a decreased peak knee flexion angle with the aligned shell and soft shell braces as well as an increased peak knee adduction angle and a reduced peak knee internal rotation angle with the aligned shell brace. Although there were alterations in lower limb mechanics during walking, induced primarily by the shell type functional brace, these changes were not deemed to considerably alter joint loading at the knee.

L'objectif du présent travail était de déterminer et de comparer le patron de modulation de l'excitabilité corticomotrice lié à l'observation, l'imagerie et l'imitation d'actions chez les jeunes âges de moins de 30 ans (n=21), les personnes âgées de plus de 55 ans (n=19) et les personnes atteintes de la maladie de Parkinson (MP) (n=11). L'action présentée sur un écran d'ordinateur 17" illustrait la main d'une personne coupant une pièce de matériel à l'aide d'une paire de ciseaux. Les potentiels moteurs évoqués induits à l'aide de la stimulation magnétique transcrânienne étaient mesurés dans le premier interosseux dorsal (FDI) et dans le court abducteur du cinquième doigt (ADM) dans quatre conditions: (1) repos, (2) observation de l'action, (3) imagerie motrice de l'action et (4) imitation de l'action. Chez les jeunes participants, l'imitation produisait la plus grande facilitation lorsque comparée au repos, suivi de l'observation et de l'imagerie qui induisaient des facilitations comparables. Ces facilitations étaient sélectives au muscle FDI puisque, dans le muscle ADM, seule l'imitation était associée à une facilitation corticomotrice. Chez les personnes âgées, le patron de facilitations était relativement semblable à celui observé chez les jeunes, à la différence que les facilitations notées dans le FDI étaient aussi présentes dans l'ADM. Quant aux patients avec la MP, les facilitations associées aux conditions d'observation et d'imagerie se sont avérées variables et inconsistantes par rapport aux personnes contrôlés du même âge. La diminution de la sélectivité chez les personnes âgées ainsi que les déficits des facilitations clicz les personnes atteintes de la MP cadrent bien avec la théorie de simulation motrice proposée par Jeannerod (2001). En effet, de tels déficits sont similaires à ceux observés chez ces populations lors de l'exécution réelle (notamment une diminution de la dextérité manuelle chez les personnes âgées et des troubles d'activation motrice chez les personnes atteintes de la MP) et appuient donc l'hypothèse selon laquelle il existerait une équivalence au niveau neural entre les états associés à la production d'actions motrices, que celles-ci soient exécutées réellement, simplement observées ou simulées mentalement.