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The reliability of anaerobic threshold and the validity of its use as an index of circulorespiratory endurance and performance capacity were investigated using coefficients of correlation and mean scores. Reliability was determined for anaerobic threshold prediction using nonlinear changes in the V̇e exercise intensity curve and for indices associated with anaerobic threshold. The validity of anaerobic threshold was established through comparison of indices related to recognized trials of functional capacity and endurance performance. Significant coefficients of reliability were produced for predicting AT from nonlinear V̇e responses. In addition, respiratory indices associated with anaerobic threshold were also found to be reliable measures of function. The validity of anaerobic threshold indices was specifically related to functional measures described by performance capacity measurements. There was no evidence to suggest that anaerobic threshold represented measures of functional capacity. It was concluded that an aerobic threshold represented a reliable measure of optimum aerobic utilization which closely followed functional measures associated with performance capacity. From results, several implications were posed for the use of anaerobic threshold. First, anaerobic threshold appeared to identify the metabolic components of exercise. Second, its use reflected a functional measure of optimum aerobic utilization. Third, it reflected exercise demand that was less strenuous resulting in fewer physiological and psychological limitations. Fourth, it implied that performance could be evaluated with respect to aerobic/anaerobic functions. A description of the investigation and the comparisons used for the determination of anaerobic threshold reliability and validity are included. / Master of Science

This study intended to determine if, by using coefficients of variation derived from data collected by Fisher [1989], it would be possible to develop prediction equations to discriminate between sincere and deceptive isokinetic knee extension tests, whether these equations could be applied to a new sample, and whether prediction accuracy is dependent on test speed. Fisher [1989] trained 76 college-age males subjects to either give a true maximal response or fake an injury during an isokinetic knee extension/flexion test at 60, 180, and 300 deg/sec. Data were transmitted to a computer running Segmental Curve Analysis [Wynn, 1988; Sebolt and Earles-Price, 1989], which computed six variables for each torque curve: peak torque (PT), torque at five degrees prior to and post-PT (T-5, T+5), area to five degrees prior to PT (A-5), area beyond five degrees post-PT (A+5), and area between five degrees pre- and post-PT (A55). Coefficients of variation were computed for each variable, which were used to develop prediction equations for each speed, and for all speeds combined. The prediction equations accurately predicted condition assignments (p = 0.572 - 0.79) when applied to Fisher's [1989] data. A second sample was solicited, trained, and tested in a manner similar to Fisher [1989], and the same prediction equations were applied. There was no significant difference (p < 0.05) in the prediction accuracy of these equations between their application to Fisher's [1989] data or to data collected in the current study. Furthermore, there appeared to be no significant effect of test speed on prediction accuracy. These data suggest that coefficients of variation could be used to discriminate between sincere and deceptive isokinetic performances. / Master of Science

A growing body of research suggests that the respiratory system may be limited in its ability to meet the demands of increased ventilitory work. This is supported by studies reporting altered contractile properties of the diaphragm in response to increased ventilations. In order to determine if expiratory muscle function is affected by increased ventilitory demand, this study evaluated maximal expiratory pressure, PeMax, in response to two separate short-term, high-intensity exercise trials. Males (n=7) and females (n=5) not currently in active physical training underwent a VO₂ max test and a constant workload of 90% of VO₂ max. PeMax was measured at rest, immediately post exercise, and at one two and five minutes into recovery for both exercise trials. PeMax values were found to decrease 12% and 17% in response to graded and constant workload conditions respectively (P<.05), and this decline persisted throughout the five minute recovery. No Significant relationship was found between magnitude of decline in PeMax and VO₂ max or decline in PeMax and Ve max. These findings suggest that maximal graded exercise as well as exhaustive constant workload exercise corresponding to 90% of VO₂ max provide the ventilitory stimulus great enough to result in a decline in expiratory performance. / Master of Science

Nesta dissertação avaliamos o pico de torque da máxima contração voluntária de diferentes grupos musculares do membro operado e não operado em pacientes submetidos à ressecção de tumores ósseos e reconstrução com endopróteses do joelho (17 pacientes) ou do quadril (11 pacientes). Foi comparado o torque do lado acometido com o não acometido e, no caso do joelho, a redução do torque das ressecções distais do fêmur (8 pacientes) com as proximais da tíbia (9 pacientes). A redução do torque dos grupos musculares responsáveis pelo movimento das articulações estudadas foi definida como a proporção da diferença entre o lado acometido e o não acometido em relação ao torque do lado não acometido. No joelho houve redução do torque extensor de 77,5% e flexor de 29,1%. Não foi encontrada diferença na redução dos torques extensor e flexor entre ressecções proximais da tíbia e distais do fêmur apesar da necessidade de reinserção do ligamento patelar no primeiro caso. A reabilitação apresentou correlação inversa e moderada com a redução do torque, mostrando a importância da atividade física para manutenção ou melhora da força muscular. Nas reconstruções do quadril houve redução de todos os grupos musculares avaliados, sendo maior para os abdutores (39%), que foi o único grupo muscular reinserido à prótese com sutura. Apesar dos resultados funcionais bons e excelentes obtidos pelo questionário Musculoskeletal Tumor Society Rating Scale (MSTS) houve redução significativa da força para todos os grupos musculares estudados. Este estudo é original na medida em que o estudo das forças musculares é pouco explorado nas endopróteses do joelho e inédito nas endopróteses do quadril. Concluímos que não houve diferença significativa da redução da força muscular quando comparadas ressecções do fêmur distal e da tíbia proximal e que a altura da patela, o surgimento de complicações e o tempo de seguimento não influenciaram a redução da força muscular nas ressecções do joelho, mas o maior tempo de reabilitação melhorou o desempenho muscular. Nas reconstruções do quadril a redução da força ocorreu em todos os grupos musculares avaliados, sendo maior para os abdutores (39%). A redução do torque abdutor mostrou ter correlação com os resultados obtidos na avaliação do questionário MSTS. / In this dissertation, the peak torque of the maximum voluntary contraction of different muscle groups of the operated and non-operated limbs was measured in patients submitted to bone tumors resection and reconstruction with knee (17 patients) or hip (11 patients) endoprosthesis. The affected side was compared to the contralateral side and the torque deficit ratio was used to compare distal femur and proximal tibia resections. The torque deficit ratio was defined as the ratio of the torque difference between the affected and non-affected sides in relation to the non-affected side torque. Extension torque deficit ratio of the knee was 77,5% and flexor torque deficit ratio was 29,1%. No difference was found in extensor and flexor torque deficit ratios between distal femur (8 patients) and proximal tibia (9 patients) resections despite the need for reinsertion of the patellar ligament in the latter case. Rehabilitation presented an inverse and moderate correlation with torque deficit ratio, showing the importance of physical activity for maintenance or improvement of muscle strength. Strength reduction was seen in all muscle groups after hip reconstruction and was more intense in abductor muscles (39,0%), which was the only muscle group reinserted to the prosthesis with suture. Despite the good and excellent functional results obtained from the Musculoskeletal Tumor Society Rating Scale (MSTS), there was a significant strength reduction of all studied muscle groups. The need for muscular reinsertion and biomechanical factors did not affect the torque deficit ratio. Muscular strength has been scarcely studied after implantation of knee endoprosthesis and never after hip endoprosthesis which turns this study original. We concluded that there was no significant difference of muscle strength deficit when comparing distal femur and proximal tibia resections and that patellar height, complication upset, and follow-up time did not influence muscle strength in the knee resections, but longer rehabilitation time improves muscle performance in knee reconstructions. In hip reconstructions, the force reduction occurred in all muscle groups evaluated, being higher for the abductors (39,0%). Abductor torque reduction was shown to correlate with the results obtained in the MSTS questionnaire.

Nesta dissertação avaliamos o pico de torque da máxima contração voluntária de diferentes grupos musculares do membro operado e não operado em pacientes submetidos à ressecção de tumores ósseos e reconstrução com endopróteses do joelho (17 pacientes) ou do quadril (11 pacientes). Foi comparado o torque do lado acometido com o não acometido e, no caso do joelho, a redução do torque das ressecções distais do fêmur (8 pacientes) com as proximais da tíbia (9 pacientes). A redução do torque dos grupos musculares responsáveis pelo movimento das articulações estudadas foi definida como a proporção da diferença entre o lado acometido e o não acometido em relação ao torque do lado não acometido. No joelho houve redução do torque extensor de 77,5% e flexor de 29,1%. Não foi encontrada diferença na redução dos torques extensor e flexor entre ressecções proximais da tíbia e distais do fêmur apesar da necessidade de reinserção do ligamento patelar no primeiro caso. A reabilitação apresentou correlação inversa e moderada com a redução do torque, mostrando a importância da atividade física para manutenção ou melhora da força muscular. Nas reconstruções do quadril houve redução de todos os grupos musculares avaliados, sendo maior para os abdutores (39%), que foi o único grupo muscular reinserido à prótese com sutura. Apesar dos resultados funcionais bons e excelentes obtidos pelo questionário Musculoskeletal Tumor Society Rating Scale (MSTS) houve redução significativa da força para todos os grupos musculares estudados. Este estudo é original na medida em que o estudo das forças musculares é pouco explorado nas endopróteses do joelho e inédito nas endopróteses do quadril. Concluímos que não houve diferença significativa da redução da força muscular quando comparadas ressecções do fêmur distal e da tíbia proximal e que a altura da patela, o surgimento de complicações e o tempo de seguimento não influenciaram a redução da força muscular nas ressecções do joelho, mas o maior tempo de reabilitação melhorou o desempenho muscular. Nas reconstruções do quadril a redução da força ocorreu em todos os grupos musculares avaliados, sendo maior para os abdutores (39%). A redução do torque abdutor mostrou ter correlação com os resultados obtidos na avaliação do questionário MSTS. / In this dissertation, the peak torque of the maximum voluntary contraction of different muscle groups of the operated and non-operated limbs was measured in patients submitted to bone tumors resection and reconstruction with knee (17 patients) or hip (11 patients) endoprosthesis. The affected side was compared to the contralateral side and the torque deficit ratio was used to compare distal femur and proximal tibia resections. The torque deficit ratio was defined as the ratio of the torque difference between the affected and non-affected sides in relation to the non-affected side torque. Extension torque deficit ratio of the knee was 77,5% and flexor torque deficit ratio was 29,1%. No difference was found in extensor and flexor torque deficit ratios between distal femur (8 patients) and proximal tibia (9 patients) resections despite the need for reinsertion of the patellar ligament in the latter case. Rehabilitation presented an inverse and moderate correlation with torque deficit ratio, showing the importance of physical activity for maintenance or improvement of muscle strength. Strength reduction was seen in all muscle groups after hip reconstruction and was more intense in abductor muscles (39,0%), which was the only muscle group reinserted to the prosthesis with suture. Despite the good and excellent functional results obtained from the Musculoskeletal Tumor Society Rating Scale (MSTS), there was a significant strength reduction of all studied muscle groups. The need for muscular reinsertion and biomechanical factors did not affect the torque deficit ratio. Muscular strength has been scarcely studied after implantation of knee endoprosthesis and never after hip endoprosthesis which turns this study original. We concluded that there was no significant difference of muscle strength deficit when comparing distal femur and proximal tibia resections and that patellar height, complication upset, and follow-up time did not influence muscle strength in the knee resections, but longer rehabilitation time improves muscle performance in knee reconstructions. In hip reconstructions, the force reduction occurred in all muscle groups evaluated, being higher for the abductors (39,0%). Abductor torque reduction was shown to correlate with the results obtained in the MSTS questionnaire.

Expiratory muscle strength training (EMST) is a resistance exercise targeting the expiratory musculature that has predominated rehabilitation research for cough and swallowing. While there have been consistent improvements in expiratory muscle strength with EMST, and promising findings in cough and swallowing, there remains a substantial gap in our understanding of the physiologic adaptations associated with training and how to optimize rehabilitative outcomes. This dissertation consists of two studies aimed at refining EMST protocols for cough and swallowing rehabilitation. Chapter 1 is an introduction that provides an overview of exercise prescription principles, outlines what is known related to exercise protocols and EMST outcome measures, and finally describes the current research gaps and dissertation aims. Chapter 2 focuses on quantifying the relationship between resistive load and ratings of perceived exertion (RPE) during EMST, examines variability in RPE in healthy adults, and compares RPE using two respiratory devices. In Chapter 3, we examine the impact of modifying exercise parameters on physiologic adaptations and RPE, while also beginning to establish links between EMST, cough, and swallowing by assessing task specificity. Chapter 4 synthesizes the research findings into the greater scientific literature, discusses the clinical implications of this work, outlines limitations, and suggests avenues for future research.

Caffeine is the most widely consumed socially acceptable drug in the world and is commonly used for its ergogenic properties with demonstrated performance enhancing effects in endurance, power and strength based activities. Despite a wealth of evidence concluding a caffeine induced performance benefit, the direct effects of the drug on peripheral physiological processes have not been fully examined. Early works showed high dose caffeine has direct force potentiating effect on skeletal muscle, a notion that has only recently been confirmed by James et al. (2005) to also occur at a maximal human physiological concentration (70µM). The present research, using mouse muscle as a model for mammalian muscle in general, provides an in-depth assessment of the direct effect of physiological concentrations of caffeine on isolated skeletal muscle performance. This research uniquely: quantifies the dose response relationship; assesses the effects of caffeine on maximal and sub maximal muscle power output and fatigue; looks at the relationship between muscles with different fiber type compositions. As high concentrations of caffeine and taurine are a constituent of many energy drinks, the suggested interaction of these ingredients to further potentiate muscle mechanical performance was also assessed. The study further examines how mammalian muscle mechanical properties change over an age range of development to aged, and how this differs between muscles with predominantly different anatomical locations and functions. In light of this the age related direct effect of physiological concentrations of caffeine was assessed in order to examine whether the ergogenic benefit changed with age. The present results demonstrate a direct muscle performance enhancing effect of physiological concentrations of caffeine that is likely to promote greater benefit on long duration endurance based activities. Furthermore, the present study demonstrates that there is no direct effect of physiological concentrations of taurine and no further performance enhancing benefit when combined with caffeine. Finally this research uniquely highlights the muscle specific age related changes in mechanical performance and further indicates that the direct effect of caffeine changes with age.

Introdução: A função principal do ligamento anterolateral (LAL) é a restrição secundária da rotação medial da tíbia, alterando o teste Pivot shift. Os estudos evidenciam uma piora da estabilidade rotacional quando há lesão do LAL associada ao ligamento cruzado anterior (LCA), que é melhorada após a reconstrução combinada desses ligamentos, mas quanto às alterações na função muscular, não há esclarecimento na literatura de como esses indivíduos se comportam. Objetivo: Analisar se há diferença na função muscular flexora e extensora do joelho e abdutora do quadril entre os grupos com indicação para reconstrução combinada do LCA e LAL (grupo LCA+LAL) e reconstrução isolada do LCA (grupo LCA), e secundariamente realizar avaliação clínica e da funcionalidade. Métodos: Avaliação por dinamometria isocinética para o objetivo primário utilizando as velocidades angulares 60º/s para o quadril e 60 e 120º/s para o joelho e para o secundário, uso da escala Lysholm e testes funcionais, como o Single Hop Test e Cross Over Hop Test e avaliação clínica da dor, pela escala visual analógica; translação anterior da tíbia, com o artrômetro (KT-1000) e perimetria do joelho e da coxa (fita métrica). Resultados: Nenhuma diferença foi encontrada quanto a função muscular do quadril e joelho no membro acometido ao se comparar os grupos LCA+LAL e LCA. Entretanto, observou-se um menor trabalho total extensor a 60º/s no membro contralateral ao lesionado observada no grupo LCA+LAL em relação ao grupo LCA e na avaliação da diferença entre os membros houve uma maior diferença entre eles no grupo LCA referente a função extensora do joelho (pico de torque, trabalho total e relação agonista/antagonista) a 60º/s, o que também ocorreu a 120º/s para o trabalho total extensor e relação agonista/antagonista do joelho para esse grupo. Quanto as variáveis secundárias, 68,9% do grupo LCA+LAL referiram dor no joelho e 61,9% no grupo LCA e houve um aumento significativo da translação anterior da tíbia no LCA+LAL em relação ao LCA. Conclusão: Não há diferença entre os grupos LCA+LAL e LCA no que se refere a função muscular do quadril e joelho e funcionalidade. O grupo LCA+LAL apresentou uma maior translação anterior da tíbia em relação ao grupo LCA / Introduction: The main function of the anterolateral ligament (ALL) is the secondary restriction of tibial medial rotation, resulting in a change on the Pivot shift test. Studies show a worse rotational stability when there is an ALL lesion associated with an anterior cruciate ligament (ACL) lesion, which is improved after the combined reconstruction of these ligaments. Regarding the alterations on muscle function, there is no understanding in the literature on how these individuals behave. Purpose: To analyze if there is a difference in the muscle function (knee flexor and extensor and hip abductor) between the groups with indication for combined ACL and ALL reconstruction (ACL+ALL group) and isolated ACL reconstruction (ACL group). Secondarily, to do a clinical and functional evaluation. Methods: Isokinetic dynamometry for the primary objective using 60º/s angular velocities for the hip and 60 and 120º/s for the knee. Secondarily, the use of the Lysholm scale and functional tests, such as Single Hop Test and Cross Over Hop Test and clinical evaluation of pain by visual analogue scale; anterior translation of the tibia, with the arthrometer (KT-1000) and perimetry of the knee and thigh (tape measure). Results: No differences were found regarding hip and knee muscle function in the affected limb when the ACL+ALL and ACL groups were compared. However, there was a lower total extensor work at 60º/s in the limb contralateral to the lesion observed in the ACL+ALL group in relation to the ACL group. Evaluating the difference between the members there was a greater difference between them in the ACL group (peak torque, total work and agonist/antagonist ratio) at 60º/s, which also occurred at 120º/s for total extensor work and knee agonist / antagonist relation for this group. Regarding the secondary variables, 68.9% of the ACL+ALL group reported knee pain and 61.9% in the ACL group, and there was a significant increase in anterior tibial translation in the ACL+ALL group in relation to the ACL group. Conclusion: There is no difference between ACL+ALL and ACL groups regarding hip and knee muscle function and functionality. The ACL+ALL group presented a greater anterior translation of the tibia in relation to the ACL group