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京都大学 / 新制・課程博士 / 博士(人間健康科学) / 甲第24097号 / 人健博第104号 / 新制||人健||7(附属図書館) / 京都大学大学院医学研究科人間健康科学系専攻 / (主査)教授 黒木 裕士, 教授 青山 朋樹, 教授 松田 秀一 / 学位規則第4条第1項該当 / Doctor of Human Health Sciences / Kyoto University / DFAM

La maladie pulmonaire obstructive chronique (MPOC) est une maladie chronique se situant au 4e rang mondial en terme de mortalité et qui affecte près d’un demi-million de personnes au Québec. Les patients avec une MPOC présentent une détérioration progressive de leur fonction respiratoire, associée notamment à des épisodes de toux et de dyspnée de plus en plus invalidante. La diminution de la tolérance à l’effort, du statut fonctionnel et de la qualité de vie sont des conséquences habituelles de la maladie. Parmi les nombreuses répercussions systémiques caractéristiques de la MPOC, la diminution de la force des muscles locomoteurs est un meilleur prédicteur de mortalité que la fonction respiratoire seule. Son évaluation fait à ce titre partie des recommandations internationales de prise en charge des patients avec une MPOC. Malgré ces recommandations, l’évaluation de la fonction musculaire n’est pas systématique dans les milieux cliniques. Les objectifs de ce mémoire sont donc de faire un état des connaissances recueillies pendant mon cheminement post-gradué et de présenter les résultats d’un projet de recherche visant à 1) évaluer les propriétés métrologiques (fidélité test-retest et validité de construit) et la faisabilité d’un protocole standardisé d’évaluation de la force maximale volontaire isométrique du quadriceps avec un dynamomètre manuel commercial fixé (CMVi-DM) chez des patients avec une MPOC, et 2) déterminer les associations entre la CMVi-DM du quadriceps et la capacité fonctionnelle de ces patients (évaluée avec le test composite Short Physical Performance Battery [SPPB]). Le protocole standardisé de CMVi-DM a démontré une excellente fidélité test-retest et une bonne validité de construit avec les mesures obtenues avec un dynamomètre informatisé (mesure-étalon). Les CMVi-DM étaient faiblement associées avec les sous-composantes de vitesse de marche et d’équilibre du SPPB, mais pas avec le temps pris pour compléter le test de cinq levers de chaise du SPPB ni le score total du test. Ces résultats permettent de conclure qu’un protocole standardisé d’évaluation de la CMVi-DM procure des valeurs reproductibles et valides chez les patients canadiens avec une MPOC, mais que l’évaluation de la force isométrique du quadriceps ne permet pas de statuer sur la capacité fonctionnelle des patients

Thesis (M.Tech.:Chiropractic)-Dept. of Chiropractic, Durban Institute of Technology, 2005 120 leaves / Low back pain has been shown to be associated with inhibition of the lower limb musculature. This inhibition is called arthrogenic muscle inhibition (AMI). Sacroiliac joint dysfunction has been linked with AMI of the ipsilateral and contralateral quadriceps and hamstring muscles. Sacroiliac manipulation has been shown to significantly reduce ipsilateral AMI, however no studies have been conducted to illustrate the effect of sacroiliac manipulation on contralateral AMI. Neither have their been studies to show the presence or extent of spinal dysfunction between the levels of L2-L5 and its significance on muscle inhibition in the quadriceps and hamstring muscles, nor the effect of manipulation of these levels on AMI of the quadriceps and hamstring muscles. The purpose of this study was therefore to determine whether spinal manipulation has an effect on AMI of the contralateral limb as well as that of the ipsilateral limb.

The main aim of this thesis was to examine hamstrings anatomy and its influence on knee flexor muscle function in healthy young men. A secondary aim was to better understand the implications of hamstrings anatomy and function, and their variability, in relation to the risk of strain injury. The functional and conventional H:Q ratios (examined up to high angular velocities) as well as the knee joint angle-specific isometric H:Q ratio exhibited good test-retest reliability at joint positions that closely replicated the conditions of high injury risk. Football players did not exhibit any differences in angle-specific or peak torque H:Q ratios compared to recreationally active controls. Knee extensor and flexor strength, relative to body mass, of footballers and controls was similar for all velocities, except concentric knee flexor strength at 400° s-1 (footballers +40%; P < 0.01). Muscle volume explained 30-71% and 38-58% of the differences between individuals in knee extensors and flexors torque respectively across a range of velocities. A moderate correlation was also found between the volume of these antagonistic muscle groups (R2= 0.41). The relative volume of the knee extensors and flexors explained ~20% of the variance in the isometric H:Q ratio and ~31% in the high velocity functional H:Q ratio. Biceps femoris long head exhibited a balanced myosin heavy chain isoform distribution (47.1% type I and 52.9 % total type II) in young healthy men, while BFlh muscle composition was not related to any measure of knee flexor maximal or explosive strength. Biceps femoris long head proximal aponeurosis area varied considerably between participants (>4-fold) and was not related to biceps femoris long head maximal anatomical cross-sectional area (r= 0.04, P= 0.83). Consequently, the aponeurosis:muscle area ratio exhibited 6-fold variability (range, 0.53 to 3.09; CV= 32.5%). Aponeurosis size was not related to isometric or eccentric knee flexion strength. The findings of this thesis suggest that the main anatomical factor that contributes to knee flexors function in vivo is hamstrings muscle size, while muscle composition and aponeurosis size do not seem to have a significant influence. The high inter-individual variability of the biceps femoris long head proximal aponeurosis size suggests that a disproportionately small aponeurosis may be a risk factor for strain injury. In contrast, biceps femoris long head muscle composition does not seem to explain the high incidence of strain injuries in this muscle. Quadriceps and hamstrings muscle size imbalances contribute to functional imbalances that may predispose to strain injury and correction of any size imbalance may be a useful injury prevention tool. Finally, regular exposure to football training and match-play does not seem to influence the balance of muscle strength around the knee joint.

Embora a analise no domínio da freqüência do sinal Eletromiográfico (EMG) seja empregada na caracterização do processo de fadiga muscular localizada sua aplicação, especificamente a da Freqüência Mediana (Fmed), é pouco explorada para a determinação do Limiar de Fadiga Eletromiográfico (LFE). Neste estudo foram realizadas análises baseadas em procedimentos experimentais executados em três diferentes modalidades de exercício: i) isométrico; ii) isotônico com peso fixo; iii) isotônico no cicloergômetro; onde foi monitorado o comportamento da Fmed do sinal EMG em três porções do músculo quadríceps femoral: vasto lateral, vasto medial e reto femoral. Os resultados demonstraram ser possível determinar o LFE através da monitoração da Fmed, em qualquer modalidade de exercício para todas as três porções musculares avaliadas. Entretanto, para o exercício isométrico e isotônico com peso fixo a qualidade dos ajustes, utilizados para o calculo do LFE, apresentou melhores índices estatísticos em comparação com os resultados obtidos no cicloergômetro. Pode ser considerado um reflexo deste comportamento a menor variação nos valores do LFE observada nas duas primeiras modalidades de exercício. Por conseqüência, nestas modalidades, uma melhor caracterização do LFE, relacionada sua definição teórica, foi observada. A análise complementar das bandas de freqüência isoladas demonstrou a possibilidade de melhoramentos relacionados ao processo metodológico de tratamento do sinal EMG para determinação do LFE. Entende-se que a determinação do LFE é uma temática controversa, porém ao mesmo tempo apresenta um grande potencial de exploração científica caracterizando, neste contexto, a contribuição deste estudo para a área / Tthough the analysis in the frequency domain of the Electromyographic Signal (EMG) was used in the characterization of the localized muscular fatigue process their application, specifically the Median Frequency (MF), is rarely explored for the determination of Electromyographic Fatigue Threshold (EMGFT). In this study analysis based in experimental procedures were executed in three different modalities of exercise: i) isometric; ii) dynamic with fixed load; iii) dynamic in the cycle ergometer; where was monitored the behavior of the EMG signal through the MF in three portions of the quadriceps muscle: vastus lateralis, vastus medialis and rectus femoris. The results demonstrated that the determination of EMGFT through the monitorization of MF was possible, in any modality of exercises for all the three muscular portions evaluated. However for the isometric and dynamic exercise with fixed load the quality of the adjustments, used for estimate the EMGFT, presented better statistical index in comparison with the results obtained in the cycle ergometer. May be considered a reflex of this behavior the smallest variation in the values of EMGFT observed in the first two modalities of exercise. For consequence, in these modalities, a better characterization of EMGFT was observed when related with your theoretical definition. The complemental analysis of the isolated bands of frequency demonstrated the possibility of improvement related in the methodological process of EMG signal processing for determination of EMGFT. The understanding around the determination of EMGFT demonstrated a controversial theme, however at the same time it presents a great potential of scientific exploration characterizing, in this context, the contribution of present study for this area

Background: The incidence of anterior cruciate ligament (ACL) –injury is 3-5 times greater in female athletes compared to male athletes. This may be partially attributed to lower levels of hamstring-quadriceps co-contraction in females with subsequent knee kinematics that increases risk of ACL-injury. Finding training methods that improves co-contraction and increases knee stability is important. Objectives: To evaluate the effects of a new device on hamstring-quadriceps co-contraction and to investigate if training with the device can alter knee kinematics in female athletes. Study design: Controlled experimental study design with repeated measures. Method: Twenty soccer and floor ball athletes were measured with electromyography (EMG) for hamstring-quadriceps co-contraction while performing squats with and without the device. Thirteen athletes also underwent three-dimensional kinematic analyses, measuring knee abduction angles (at initial ground contact and peak angle) during a drop jump, before and after a six week intervention period with the device. Friedman’s test and Wilcoxon signed rank test was used to assess differences and effect sizes (ES) were calculated. Results: Co-contraction was consistently larger on the device (medial side: p&lt;0.001, ES=0.88; lateral side: p&lt;0.001, ES=0.80) and the ratio of medial-to-lateral co-contraction increased (p=0.001, ES=0.79). In the kinematic analysis low adherence rates amongst our subjects meant that the effects of the device on kinematics could not be measured. Conclusion: Performing squats with the new training device stimulates increased hamstring-quadriceps co-contraction and increases the ratio of medial-to-lateral co-contraction. The effects of the device on knee kinematics have yet to be determined.

Pagal pasaulinę sveikatos organizaciją, sveikata — tai fizinė, dvasinė ir socialinė gerovė, o ne tik ligos ar negalios nebuvimas. Svarbus sveikatą veikiantis veiksnys yra aplinkos temperatūra. Kiekvieno žmogaus organizmas puikiai geba prisitaikyti prie kintančių aplinkos temperatūros sąlygų, tačiau skirtingi žmonės įvairiai reaguoja į temperatūros pasikeitimus. Padidėjus žmogaus kūno temperatūrai gali įvykti perkaitimas — hipertermija. Probleminis klausimas. Ar dirbtinėmis sąlygomis sukėlus hipertermiją, moterų organizmas adaptuosis prie jos? Ar hipertermija riboja raumens funkcines galimybes atliekant maksimalaus intensyvumo izometrinius pratimus? Tyrimo tikslas buvo įvertinti aklimatizacijos hipertermijai ��taką moterų organizmui. Tyrimo tikslui pasiekti iškelti uždaviniai: 1. Nustatyti hipertermijos poveikį tiriamųjų širdies susitraukimų dažniui bei pulsiniam spaudimui. 2. Nustatyti tiriamųjų rektalinės, odos, bendrą kūno temperatūrų kaitą ir netenkamą kūno svorį sukėlus hipertermiją. 3. Įvertinti tiriamųjų subjektyvų šiluminį pojūtį, šiluminį komfortą bei šiluminį stresą sukėlus hipertermiją. 4. Nustatyti hipertermijos poveikį maksimaliai valingai jėgai ir centriniam nuovargiui, atliekant 2 min. maksimalų izometrinį krūvį. Išanalizavus tyrimo rezultatus nustatyta, kad septynis kartus kas antrą dieną pasyviai šildant kūną, įmerkiant kojas į vandenį, kur vandens temperatūra 44oC, bei taikant maksimalios valingos jėgos 2 minučių krūvį (MVJ-2 min.), organizmo aklimatizacija... [toliau žr. visą tekstą] / According to the world health organization, health is physical, spiritual and social well-being and not just the absence of illness or disability. An important factor that affects health is the environmental temperature. Every person’s body can adapt well to changing environment conditions, however different people react in a variety of ways to changes in temperature. Increase in human body temperature can lead to overheating - hyperthermia. The goal of the research was to evaluate the effect of acclimatization to hyperthermia to the fatigue of skeletal muscles of adult women when performing maximum intensity isometric exercises. Tasks in order to reach the goal of the research: 1. To determine the effect of hyperthermia to the subjects' heart contraction rate and pulse pressure. 2. To determine the variation of the subjects' rectal, skin and general body temperature and body weight loss during induced hyperthermia. 3. To evaluate the subjective heat sensation, heat comfort and heat stress of the subjects during induced hyperthermia. 4. To determine the effect of hyperthermia to maximum volitional strength and central fatigue when performing maximum 2 min. isometric load. After analysing the results of the research it was found that by passively heating the body every two days seven times in total, by immersing feet into water, whose temperature is 44 oC, and by applying maximum volitional strength 2 minute load (MVJ-2 min.), the acclimatisation of the body to... [to full text]

The broad aim of this thesis was to progress understanding of the neuromechanics of joint stability and injury mechanisms by investigating the interactions between neuromuscular function and balance perturbations as well as the influence of sex and fatigue on these variables. Knee extensor (KE) and plantar flexor (PF) isometric strength parameters (maximum voluntary torque (MVT), explosive voluntary torque (EVT)) were related in young healthy adults. EVT of KE and PF were correlated at 4/5 time points during the rising torque-time curve for all absolute (r = 0.488-0.755) and relative (to body mass (BM) (r = 0.517-0.669) and MVT (r = 0.353-0.480)) expressions of EVT. These results suggest that KE and PF function is related for both maximum and explosive torque. Males were stronger for KE (+89%) and PF (+55%) than females. Males also displayed greater EVT at all time points in KE (+57-109%) and at 50-150 ms in PF (+33-52%). When MVT and EVT were normalised to BM, males continued to be stronger at all time points in KE (+23-60%) and from 100-150 ms (18-20%) in PF. No sex differences were found when EVT was normalised to MVT. Furthermore, sex differences were discovered in muscle morphology. Females had a smaller knee flexor (KF):KE size ratio, a proportionately small sartorius (SA) and gracilis (GR) and a proportionately larger vastus lateralis (VL), potentially predisposing females to greater risk of ACL injury. Females had a larger biceps femoris long head (BFlh) as a proportion of the KF than males, which may contribute to the higher risk of hamstring strain injury (HSI) in males. Regarding explosive performance and perturbation response, explosive PF torque had a weak to moderate correlation with COM displacement (COMD) from 400-500 ms (r = -0.346 to -0.508) and COM velocity (COMV) from 300-500 ms (r = -0.349 to -0.416), with weaker correlations between explosive KE torque and COMV at 400 ms (r = -0.381 to -0.411) but not with COMD. These findings suggest that greater explosive torque results in better control of the COM in response to unexpected perturbations. The effects of football simulated fatigue on these factors resulted in reduced maximal KF and KE torque. However, football simulated fatigue was not found to reduce EVT of either muscle group, or explosive H/Q ratio. Football simulated fatigue resulted in impaired balance response to unexpected perturbation in the posterior but not the anterior direction.

A estimulação elétrica neuromuscular e a laserterapia de baixa potência têm se mostrado isoladamente efetivas no tratamento da osteoartrite de joelho. A estimulação elétrica neuromuscular parece contribuir com a restauração da força e estrutura do músculo quadríceps femoral, enquanto que a laserterapia parece ser efetiva no controle do processo inflamatório e da dor, bem como na regeneração da cartilagem. A hipótese de que a adição da laserterapia à estimulação elétrica neuromuscular poderia reduzir a dor articular associada à inflamação e consequentemente potencializar os efeitos da estimulação elétrica sobre o sistema muscular motivou a realização do presente estudo. O tema da presente tese de Doutorado é o uso combinado da estimulação elétrica neuromuscular e da laserterapia de baixa potência no tratamento da osteoartrite de joelho em idosos: efeitos sobre parâmetros neuromusculares e funcionais. No Capítulo I, um estudo de revisão sistemática classificou os níveis de evidência científica sobre a efetividade da estimulação elétrica neuromuscular no fortalecimento do quadríceps de idosos com osteoartrite de joelho. Após busca sistematizada nas bases de dados, 9 estudos contemplaram os critérios de inclusão e foram incluídos na revisão. Os resultados principais indicam que existe moderada evidência científica a favor do uso da estimulação elétrica neuromuscular sozinha ou combinada com exercício para o fortalecimento muscular isométrico do quadríceps em idosos com OA de joelho. Apesar dos resultados promissores da estimulação elétrica neuromuscular sobre a força, faltam dados na literatura sobre seus efeitos sobre a massa muscular. Além disso, não foram encontrados estudos sobre o potencial do efeito combinado da laserterapia e estimulação elétrica no tratamento da osteoartrite. Para preencher essa lacuna na literatura, dois estudos originais foram desenvolvidos para verificar: (1) a adaptação neuromuscular e funcional dos extensores de joelho de idosos com osteoartrite à estimulação elétrica neuromuscular em combinação à laserterapia de baixa potência (Capítulo II); e (2) as adaptações na arquitetura do principal extensor de joelho e na capacidade funcional de idosos decorrentes do uso combinado da estimulação elétrica neuromuscular e da laserterapia de baixa potência (Capítulo III). Quarenta e cinco idosas com osteoartrite de joelho foram submetidas a um período controle de quatro semanas sem intervenção seguido por um período de oito semanas de intervenção ou com estimulação elétrica neuromuscular, ou com laserterapia ou com estimulação elétrica neuromuscular em adição à laserterapia. Avaliações de torque, eletromiografia, ultrassonografia e testes funcionais foram realizados antes e após o período controle, assim como após de oito semanas de intervenção. Questionário específico sobre a funcionalidade de idosos com osteoartrite foi aplicado antes e depois das intervenções. As três intervenções geraram aumentos no torque, na ativação muscular, bem como melhorias na funcionalidade. Os valores de espessura muscular, área de secção transversa anatômica e ângulo de penação aumentaram após os tratamentos com estimulação elétrica neuromuscular, mas não com laserterapia. Nossos achados sugerem que: (1) a estimulação elétrica sozinha ou combinada à laserterapia é igualmente efetiva para gerar adaptações neuromusculares e funcionais; (2) a estimulação elétrica sozinha ou combinada gera aumentos no ângulo de penação e na espessura muscular, mas não no comprimento fascicular; (3) o ganho de força obtido pela estimulação elétrica é desproporcional aos incrementos neurais e morfológicos; (4) a laserterapia sozinha é capaz de melhorar a funcionalidade do idoso provavelmente por meio da redução da dor e do aumento da ativação muscular; (5) o uso de programa de estimulação elétrica neuromuscular com intensidades e volumes progressivos é efetivo na promoção da hipertrofia muscular; (6) a laserterapia não potencializa os efeitos da estimulação elétrica neuromuscular sobre os parâmetros neuromusculares e funcionais. / Neuromuscular electrical stimulation alone and low-level laser therapy alone have been effective in the treatment of knee osteoarthritis. Neuromuscular electrical stimulation seems to contribute to the reestablishment of strength and structure in the quadriceps muscle, whereas low-level laser therapy seems to contribute to the reduction of the pain and of the inflammatory process and to the promotion of cartilage regeneration. The hypothesis that the association of low-level laser therapy with neuromuscular electrical stimulation could reduce joint pain associated with the inflammation and consequently potentiates the effects of electrical stimulation on the muscular system motivated the present study. The theme of this PhD thesis is the combined use of neuromuscular electrical stimulation and low-level laser therapy in the treatment of knee osteoarthritis in the elderly: effects on neuromuscular and functional parameters. In Chapter I, a systematic review rated levels of scientific evidence on the effectiveness of neuromuscular electrical stimulation on quadriceps strengthening in elderly with knee osteoarthritis. After systematic search in databases, 9 studies contemplated the inclusion criteria and were included in the review. The main results indicate that there is moderate scientific evidence in favour the use of neuromuscular electrical stimulation alone or combined with exercise to strengthen the quadriceps muscle in elderly with knee osteoarthritis. Despite the promising results of neuromuscular electrical stimulation on strength, data are lacking in the literature about its effects on muscle mass. Moreover, no studies were found on the potential effect of the combination of low-level laser therapy and neuromuscular electrical stimulation in the treatment of osteoarthritis. To fill this gap, two original studies were developed to verify: (1) neuromuscular and functional adaptation of knee extensors in elderly patients with osteoarthritis to neuromuscular electrical stimulation in combination with low-level laser therapy (Chapter II); and (2) the changes in the architecture of the vastus lateralis muscle and in the functional ability of elderly patients with osteoarthritis to the combined use of neuromuscular electrical stimulation and low-level laser therapy (Chapter III). Forty-five elderly female individuals with knee osteoarthritis were submitted to a four-week control period with no intervention followed by an eight-week period of intervention with neuromuscular electrical stimulation, low-level laser therapy, or neuromuscular electrical stimulation in combination with low-level laser therapy. Knee extensor evaluations of torque, electromyography, ultrasonography and functional tests were performed before and after the control period as well as after eight weeks of intervention. Questionnaire regarding the functionality of elderly patients with osteoarthritis was applied before and after interventions. The three interventions generated increases in torque, muscle activation, as well as improvements in functionality. The values of muscle thickness, anatomical cross-sectional area and pennation angle increased after treatment with neuromuscular electrical stimulation, but not with low-level laser therapy. Our findings suggest that: (1) electrical stimulation alone or combined with laser therapy is equally effective to generate neuromuscular and functional adaptations; (2) electrical stimulation alone or combined with laser therapy increases pennation angle and muscle thickness, but not fascicle length; (3) gain strength obtained by the electrical stimulation is disproportionate to increases in neural and morphological parameters; (4) low-level laser therapy alone is able to improve the elderly functionality; (5) the use of neuromuscular electrical stimulation with increasing intensities and progressive volumes is effective in promoting muscle hypertrophy; (6) low-level laser therapy does not potentiate the effects of neuromuscular electrical stimulation on neuromuscular and functional parameters.