O objetivo do presente estudo foi analisar os efeitos de um treinamento de 12 semanas do Método Pilates (MP) no solo sobre variáveis fisiológicas e biomecânicas da corrida em duas velocidades diferentes. A amostra foi dividida aleatoriamente em dois grupos, sendo 16 para o grupo controle (GC) e 16 para o grupo Pilates (GP). O GC realizou um treinamento de 12 semanas de corrida, enquanto o GP realizou o treinamento de corrida combinado com o treinamento do MP, este realizado em dias alternados. Previamente ao início do treinamento, os sujeitos foram familiarizados com procedimentos e equipamentos. Para análise de desempenho em prova, realizou-se uma prova de 5 quilômetros em pista antes do início do treinamento e após o seu término. Em uma sessão específica de testes foram mensurados o custo metabólico (Cmet) e ativação eletromiográfica nas fases de pré-ativação, fase de apoio e fase de balanço da passada referentes aos músculos obliquus internus abdominis (OI), obliquus externus abdominis (OE), gluteus medius (GM), longissimus (LO), latissimus dorsi (LA), biceps femoris (BF) e vastus lateralis (VA) durante a corrida em esteira nas velocidades de 10km.h-1 e 12km.h- 1. Os dados eletromiográficos foram normalizados através da amplitude isométrica máxima do sinal eletromiográfico obtido em teste específico para cada músculo. As fases de movimento foram definidas através da filmagem de forma sincronizada à coleta EMG no último minuto de cada estágio de corrida. Para a análise entre os grupos, no período prétreinamento, utilizou-se ANOVA one-way. Em caso de distribuição não-paramétrica foi utilizado o teste de Mann-Whitney. As comparações referentes às variáveis de desempenho de corrida, metabólicas, ativação muscular e caracterização da amostra, entre os fatores tempo e grupo, foram realizadas através do modelo de Equações de Estimativas Generalizadas (GEE). Como resultados, em relação ao tempo de 5km, tanto o GC (25,33 ± 0,58 min; 24,61 ± 0,52min. p=0,006) quanto o GP (25,65 ± 0,44 min; 23,23 ± 0,40min. p<0,001) apresentaram uma redução após o treinamento e GP foi significativamente mais rápido (p=0,039) comparado ao GC. Em relação a variável Cmet em 12km.h-1, as análises apresentaram uma melhora significativa quando comparados pré- e pós-treinamento para os dois grupos, e GP (4,33 ±0,07J.kg-1.m-1) teve melhores respostas comparado a GC (4,71±0,11J.kg-1.m-1) no pós-treinamento. O GP apresentou uma menor ativação comparado ao GC na fase de apoio para OI, LO, GM (p<0,05) e na fase de balanço para OE, OI, LO, GM após o treinamento. Entretanto, os músculos BF, VA e LA não apresentaram diferenças entre os grupos. Conclui-se o GP apresentou melhoras significativamente maiores comparadas ao GC no pós-treinamento para tempo de 5km e Cmet12. O GP apresentou redução no percentual de ativação muscular para OI, OE, LO e GM no pós-treinamento e foi menor do que GC evidenciando que um treinamento de corrida associado a um treinamento de MP pode proporcionar uma maior economia de corrida, através de uma menor demanda muscular o que parece influenciar o desempenho em provas de 5km. / The aim of this study was to analyze the effects of a 12-week training of Pilates Method (MP) in the physiological and biomechanical variables of running at two different speeds. The sample was randomly divided into two groups, 16 subjects for the control group (CG) and 16 subjects for the Pilates group (GP). GC held a 12 weeks of a running training program while the GP performed the running training program combined with Pilates training on alternate days. Prior to the start of training, subjects performed a familiarization session with procedures and equipment. For performance evaluation, a five kilometers running test on track was performed before and after the training period. In a specific test session, metabolic cost (Cmet) and EMG activation in the pre-activation, support and swing phase were obtained for obliquus internus abdominis (OI), obliquus externus abdominis (OE), gluteus medius (GM), longissimus (LO), latissimus dorsi (LA), biceps femoris (BF) and vastus lateralis (VA) muscles during treadmill running at speeds of 10km.h-1 and 12km.h-1. The electromyographic data were normalized by maximum isometric amplitude of the electromyographic signal obtained in specifics tests for each muscle. Motion phases were determined through a synchronized shooting during the EMG collection, wich was obtained in the last minute of each of the two running stages. For statistical analysis between groups in the pre-training period one-way ANOVA was performed. In the case of nonparametric data distribution the Mann-Whitney test was applied. Comparisons related to running performance, metabolic variables, muscle activation and characterization of the sample, among the factors time and group, were performed using the Generalized Estimation Equation Model (GEE). Regarding to the 5km performance, both the GC (25.33 ± 0.58 min;. 24.61 ± 0,52min p = 0.006) and the GP (25.65 ± 0.44 min; 23.23 ± 0, 40min. p <0.001) showed a reduction after the training program and GP was significantly faster (p = 0.039) compared to the GC. For the Cmet12 the analysis showed a significant improvement when compared pre- and post-training in both groups. Also,GP (4.33 ± 0.07) had better responses than GC (4.71 ± 0.11 ) in the post-training period. Futhermore, GP had a lower activation compared to the CG in the stance phase for OI, LO, GM (p <0.05) and in the swing phase for OE, OI, LO, GM in post-training period. The BF muscle, VA and LA did not differ between groups. In Conclusion, the GP showed significantly greater improvements compared to the GC in post-training for 5km performance and Cmet12 . Also, GP showed a reduction in the percentage of muscle activation to OI, OE, LO and GM in the post-training and was smaller than GC, showing that a running training associated with a Pilates training program can provide greater running economy through a smaller muscular demand which seems to influence performance in 5km performance test.

No description available.

The forefoot (FF) running pattern has been recently advocated to improve running economy and prevent overuse injuries compared to the rearfoot (RF) pattern. However, these claims have not been supported by empirical evidence. The purpose of this dissertation was to investigate the potential advantages of RF and FF patterns to improve running economy and reduce injury risk in 20 natural RF and 20 natural FF runners. The first study found that the RF group was more economical when performing the RF pattern at a slow, medium, and fast speed vs. FF running. Only running at the fast speed resulted in a difference in economy between footfall patterns in the FF group in which RF running was more economical. Therefore, there is no advantage of FF running for improving running economy. The results of the second study indicated that there was a weak to moderate relationship between Achilles tendon (AT) moment arm length and running with either RF or FF patterns. AT force was greater during FF running, which may increase the risk of developing tendon injury. The third study used a modeling approach to find that FF running resulted in greater elastic energy recoil in the gastrocnemius (GA) and the soleus (SO). However, greater mechanical work overall with FF running resulted in no difference in metabolic cost of the GA between footfall patterns but greater metabolic cost of the SO compared to RF running. The fourth study found that shock attenuation was greater during RF running compared to FF running. Greater shock attenuation during RF running was a result of an increased load imposed on the system. Decomposing the vertical ground reaction force in the frequency domain revealed that RF running may have a greater reliance on passive shock attenuation mechanism whereas the FF pattern may have a greater reliance on active shock attenuation mechanisms. These results suggest that previous speculation that the FF running pattern is more economical was not substantiated. It is likely that each footfall pattern exposes a runner to different types of injuries, rather than one footfall pattern being more injurious than another.

Syfte med denna studie var att undersöka energiförbrukningen vid havspaddling. Energiförbrukningen undersöktes i vila och vid två olika hastigheter (4 och 7 km/h), först med en olastad och sedan med en lastad kajak (20 kg). Dessutom undersöktes hur det passiva motståndet förändrades vid successivt ökad hastigheten. Studien genomfördes i en försöksgrupp med jämn könsfördelning och med varierande ålder och paddlingserfarenhet. I studiens första del uppmättes försökspersonernas hjärtfrekvens i förhållande till syrgasupptag och koldioxidproduktion vid en successivt ökad belastning i en kajakergometer. För varje försöksperson kunde sedan en korrelationskurva beräknas mellan hjärtfrekvens och syrgasupptag. Utifrån den hjärtfrekvens som sedan försökspersonen hade under paddlingen kunde syrgasupptaget beräknas. Vid paddling med en olastad kajak och en hastighet av 4 km/h beräknades syrgasupptaget till 5 ml/kg/min. Vid en hastighet 7 km/h så ökade syrgasupptaget signifikant till 11.5 ml/kg/min (p&lt; 0.05). Vid paddling med en lastad kajak så ökade syrgasupptaget signifikant från 6,5 ml/kg/min vid 4 km/h till 14,5 ml/kg/min (p&lt; 0.05) vid 7 km/h. Om energiförbrukningen beräknas utifrån syrgasupptaget för en person på 75 kg skulle en paddelhastighet på 4 km/h innebära en förbrukning på 458 kJ (107,4 kcal/h) med en olastad kajak och 585 kJ (139.8 kcal/h) med en lastad kajak. Vid 7 km/h var motsvarande värden 1080 kJ (258 kcal/h) (olastad kajak) och 1350 kJ (322 kcal/h) (lastad kajak). Det passiva motståndet ökade exponentiellt med ökad hastighet. / The aim of this study was to examine energy consumption when sea kayaking. The energy consumption was examined at rest and at two different speeds (4 and 7 km/h respectively), first with an empty and then with a packed kayak (20 kg). Moreover, the kayaks’ passive drag in the water was measured in order to examine how this was influenced by the speed through the water. The study was implemented in a group of paddlers with even gender distribution but with varying age and experience. In the first part of the experiment, we measured the participants’ heart frequency, oxygen uptake and carbon dioxide production during gradually increased work load in a kayakergometer. For each test subject correlation curves were constructed from the recorded heart rate and oxygen uptake. Based on the persons heart rate during paddling, oxygen uptake was calculated using the individual regression equation which was calculated in the first part of the experiment. When paddling at 4 km/h with an unpacked kayak, the oxygen uptake was measured to 5 ml/kg/min. At 7 km/h, it increased significantly to 11.5 ml/kg/min (p&lt; 0.05). Paddling with a packed kayak oxygen consumption increased to 6.5 ml/kg/min at 4 km/h and significantly to14.5 ml/kg/min at 7 km/h. If energy consumption is calculated on the basis of oxygen uptake for a person weighing 75 kg, at 4 km/h this corresponds to a consumption of 450 kJ (107.4 kcal/h) when kayaking with an unpacked kayak and 585 kJ (139.8 kcal/h) with a packed ditto. At 7 km/h, energy consumption was calculated to 1080 kJ (258 kcal/h) (empty kayak) and 1350 kJ (322 kcal/h) (packed kayak). The passive drag increased exponentially with increased speed.

Vocal fatigue is among the most debilitating conditions affecting individuals with voice disorders, with little known about its actual metabolic mechanisms. The current study aims to address this issue by investigating the hypothesis that neuromuscular inefficiency, cardiovascular recovery deficits, or both, may play a role in vocal fatigue.

No description available.

Spinal cord injury, whether traumatic or nontraumatic, can partially or completely damage sensorimotor pathways between the brain and the body, leading to heterogeneous gait abnormalities. Mobility impairments also depend on other factors such as age, weight, time since injury, pain, and walking aids used. The ASIA Impairment Scale is recommended to classify injury severity, but is not designed to characterize individual ambulatory capacity. Other standardized tests based on subjective or timing/distance assessments also have only limited ability to determine an individual's capacity. Data-driven techniques have demonstrated effectiveness in analysing complexity in many domains and may provide additional perspectives on the complexity of gait performance in persons with spinal cord injury. The studies in this thesis aimed to address the complexity of gait and functional abilities after spinal cord injury using data-driven approaches. The aim of the first manuscript was to characterize the heterogeneous gait patterns in persons with incomplete spinal cord injury. Dissimilarities among gait patterns in the study population were quantified with multivariate dynamic time warping. Gait patterns were classified into six distinct clusters using hierarchical agglomerative clustering. Through random forest classifiers with explainable AI, peak ankle plantarflexion during swing was identified as the feature that most often distinguished most clusters from the controls. By combining clinical evaluation with the proposed methods, it was possible to provide comprehensive analyses of the six gait clusters.     The aim of the second manuscript was to quantify sensorimotor effects on walking performance in persons with spinal cord injury. The relationships between 11 input features and 2 walking outcome measures - distance walked in 6 minutes and net energy cost of transport - were captured using 2 Gaussian process regression models. Explainable AI revealed the importance of muscle strength on both outcome measures. Use of walking aids also influenced distance walked, and  cardiovascular capacity influenced energy cost. Analyses for each person also gave useful insights into individual performance.     The findings from these studies demonstrate the large potential of advanced machine learning and explainable AI to address the complexity of gait function in persons with spinal cord injury. / Skador på ryggmärgen, oavsett om de är traumatiska eller icke-traumatiska, kan helt eller delvis skada sensoriska och motoriska banor mellan hjärnan och kroppen, vilket påverkar gången i varierande grad. Rörelsenedsättningen beror också på andra faktorer såsom ålder, vikt, tid sedan skadan uppstod, smärta och gånghjälpmedel. ASIA-skalan används för att klassificera ryggmärgsskadans svårighetsgrad, men är inte utformad för att karaktärisera individens gångförmåga. Andra standardiserade tester baserade på subjektiva eller tids och avståndsbedömningar har också begränsad möjlighet att beskriva individuell kapacitet. Datadrivna metoder är kraftfulla och kan ge ytterligare perspektiv på gångens komplexitet och prestation. Studierna i denna avhandling syftar till att analysera komplexa relationer mellan gång, motoriska samt sensoriska funktion efter ryggmärgsskada med hjälp av datadrivna metoder. Syftet med den första studien är att karaktärisera de heterogena gångmönster hos personer med inkomplett ryggmärgsskada. Multivariat dynamisk tidsförvrägning (eng: Multivariate dynamic time warping) användes för att kvantifiera gångskillnader i studiepopulationen. Hierarkisk agglomerativ klusteranalys (eng: hierarchical agglomerative clustering) delade upp gång i sex distinkta kluster, varav fyra hade lägre hastighet än kontroller. Med hjälp av förklarbara AI (eng: explainable AI) identifierades det att fotledsvinkeln i svingfasen hade störst påverkan om vilken kluster som gångmönstret hamnat i. Genom att kombinera klinisk undersökning med datadrivna metoder kunde vi beskriva en omfattande bild av de sex gångklustren. Syftet med den andra manuskriptet är att kvantifiera sensoriska och motoriska faktorerans påverkan på gångförmåga efter ryggmärgsskada. Med hjälp av två Gaussian process-regressionsmodeller identiferades sambanden mellan 11 beskrivande faktorer och 2 gång prestationsmått, nämligen gångavstånd på 6 minuter samt metabola energiåtgång. Med hjälp av förklarbar AI påvisades det stora påverkan av muskelstyrka på både gångsträckan och energiåtgång. Gånghjälpmedlet samt kardiovaskulär kapaciteten hade också betydande påverkan på gångprestation. Enskilda analyser gav insiktsfull information om varje individ. Resultaten från dessa studier visar på potentiella tillämpningar av avancerad maskininlärning och AI metoder för att analysera komplexa relationer mellan funktion och motorisk prestation efter ryggmärgsskada. / <p>QC 20240221</p>

L'ectrostimulation dite conventionnelle (CONV) est délivrée par des impulsions électriques de basse fréquence (≤ 50 Hz), de courte durée (< 400 μs) et de haute intensité. Ce type d'ESNM permet ainsi d'évoquer une contraction musculaire grâce à l'activation directe des axones moteurs et est associé à une fatigue musculaire exagérée par rapport aux contractions volontaires (VOL). Au contraire, lors de l'utilisation d'impulsions de longues durées (1 ms), de hautes fréquences (≥ 80 Hz) et de faibles intensités (i.e. protocole « Wide-Pulse, High-Frequency » (WPHF)), une partie de la force musculaire évoquée aurait pour origine des mécanismes centraux. En effet, une augmentation de la force produite en réponse à WPHF a été rapportée alors que l'intensité de stimulation était constante. Cette « extra force » (EF) refléterait le recrutement par voie réflexe des motoneurones spinaux. L'objectif de ce travail de thèse était de mieux appréhender les mécanismes neurophysiologiques à l'origine de l'EF et d'évaluer les conséquences métaboliques et corticales du protocole WPHF (1 ms - 100 Hz) par rapport à des protocoles d'exercices VOL et de type CONV (50 μs - 25 Hz). Les réponses musculaires des fléchisseurs plantaires et les réponses cérébrales ont été évalué par résonance magnétique nucléaire (la spectroscopie par résonance magnétique du phosphore 31 du muscle et l'imagerie par résonance magnétique fonctionnelle du cerveau) et électrophysiologie (EMG). Ces résultats constituent une première étape importante vers une meilleure prise en charge des pathologies liées à des atteintes du neuromusculaire. / Conventional neuromuscular electrical stimulation (CONV) is delivered via surface electrodes at short pulse duration (< 400 μs), low frequencies (≤ 50 Hz) and high current intensities. The motor unit recruitment pattern of CONV, however, is different from the pattern of voluntary contractions (VOL) and leads to a hastened onset of muscle fatigue. The use of wide-pulses (1ms), high frequencies (100 Hz) (WPHF) and low current intensities might approach the natural activation pattern of VOL by enhancing the neural contribution to force production. Previous studies investigating WPHF reported progressive and unexpected force increments ("Extra Forces") despite a constant stimulation intensity which might reflect the more pronounced activation of sensory pathways within the central nervous system. The objective of this thesis was to investigate this "Extra Force" (EF) phenomenon and to evaluate the efficiency of WPHF (1 ms pulse duration at 100 Hz) in terms of metabolic demand and neural contribution to force production in comparison to CONV NMES (0.05 ms pulse duration at 25 Hz) and VOL. Our experiments comprised electrophysiological (EMG) and nuclear magnetic resonance techniques (31P spectroscopy of the muscle, functional imaging of the brain). The findings should be considered in future studies investigating the potential of NMES in a clinical context as a treatment for neuromuscular pathologies.