Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed July 9, 2007). PDF text: vii, 77 p. UMI publication number: AAT 3247183. Includes bibliographical references. Also available in microfilm and microfiche formats.

Little is known about protein profiles in slow-twitch (MHC I) and fast-twitch (MHC IIa and MHC IIx) human skeletal muscle fibers. Therefore we developed a method of assessing fiber type specific protein content across the continuum of human skeletal muscle fiber types. The method presented here combines the advantages of SDS-PAGE for fiber typing with the common Western Blot (WB) technique. Individual vastus lateralis muscle fibers (n = 264) were isolated and clipped into two portions, one for fiber-typing and one for protein identification. Following fiber type determination, WB destined fiber segments were combined into fiber type specific pools (20 fibers/pool) and assessed for GAPDH, actin, Citrate Synthase, and total p38 content. GAPDH expression was 69%, 92%, 159%, and 200% more abundant in MHC I/IIa, MHC IIa, MHC IIa/IIx, and MHC IIx pools when compared to MHC I, respectively. Inversely, Citrate synthase content was 526%, 497%, 316%, and 47% more abundant in MHC I, MHC I/IIa, MHC IIa, and MHC IIa/IIx when compared to MHC IIx, respectively. Similar to GAPDH, total p38 expression was 67% greater in MHC IIa versus MHC I fibers. These data establish a novel application of WB combined with SDS-PAGE for fiber type specific protein analysis in human skeletal muscle. These initial results show content of particular proteins exist in a hierarchal fashion throughout the continuum of human skeletal muscle fiber types. Application of these methods will enhance our understanding of skeletal muscle health profiles among physically active and clinically based populations. / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science

Bakgrund: Vastus medialis kan delas in i två olika komponenter beroende på fiberriktning. Den nedre delen vastus medialis oblique (VMO) har sitt ursprung från adductor magnus och drar patella medialt medans vastus lateralis (VL) drar patella lateralt. En obalans mellan VMO och VL kan leda till avvikelse i patellas position och rörelse vilket är en orsak till patellofemoralt smärtsyndrom (PFSS). En aktivering av adductor magnus sätter VMO på sträck vilket leder till bättre kontraktionskraft av VMO. Knäböj utförda på instabilt underlag har visat på en ökad aktivering av VMO. Syfte: Syftet var att göra en initial pilotstudie för att undersöka skillnaden i muskelaktivering av VMO vid knäböj på stabilt underlag jämfört med en knäböj på instabilt underlag med samtidig aktiv höftadduktion. Metoden: Friska unga män utförde knäböj på instabilt underlag med aktiv höftadduktion respektive knäböj på stabilt underlag. Utfallsvariablar var EMG-amplitud på VMO och VL samt kvoten VMO:VL. Resultatet: Samtliga fem deltagare fick minskad muskelaktivering av VMO i övningen knäböj på instabilt underlag med aktiv höftadduktion jämfört med knäböj på stabilt underlag. Två av fem deltagare fick högre VMO:VL-kvot i övningen knäböj på instabilt underlag med aktiv höftadduktion. Konklusion: Resultatet tyder på att en knäböj på instabilt underlag med samtidig aktiv höftadduktion jämfört med en knäböj på stabilt underlag inte ger en ökad aktivering av VMO eller en högre VMO:VL-kvot hos friska unga män. Utifrån resultaten och tidigare studier inom området behövs det mer studier med vissa metodologiska förändringar för att en given slutsats ska kunna dras.

Made available in DSpace on 2014-06-12T23:03:32Z (GMT). No. of bitstreams: 2 arquivo8812_1.pdf: 648581 bytes, checksum: 10ce890b7d2ab8a0cd1beaa42e9700d0 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / As distrofias musculares (DM) constituem um grupo heterogêneo de desordens geneticamente determinadas e acompanhadas de destruição progressiva de fibras musculares, que se manifestam com fraqueza progressiva e perda da massa muscular, iniciando-se geralmente na infância. A distrofia muscular de Duchenne (DMD) é uma desordem recessiva ligada ao cromossomo X, sendo considerada a mais comum e grave das distrofias em crianças, para qual não existe terapia efetiva. Este estudo objetivou analisar, através da histoquímica e morfometria, a predominância dos tipos de fibras musculares estriadas esqueléticas em pacientes com DMD. Biópsias do músculo vastus lateralis foram coletadas de cinco pacientes, do sexo masculino, com faixa etária de 13 a 15 anos, com diagnóstico clínico de DMD, no Setor de Neuropatologia do Hospital das Clínicas da Universidade Federal do Rio de Janeiro, no período de agosto de 2004 a junho de 2005. Amostras foram coradas pelo método histoquímico para a ATPase miofibrilar (ATPases 9,6;4,6 e 4,3). A análise morfométrica realizada no nosso estudo revelou que as fibras musculares do tipo I apresentaram valores percentuais maiores do que as fibras IIa e IIb em todos os pacientes; além disso, as fibras musculares do tipo I apresentaram diâmetro e área maiores do que as fibras do tipo IIa e IIb, porém, com valores muito próximos, estando estes resultados de acordo com os achados da literatura. As análises histoquímica e morfométrica realizadas na avaliação dos pacientes dessa pesquisa demonstraram ser ferramentas importantes no auxílio do diagnóstico qualitativo e quantitativo das fibras musculares esqueléticas acometidas nesse tipo de doença

Research data indicates a persistence of elevated muscle glycogen concentration 3 days post-supercompensation in resting athletes. This study expands our earlier findings by determining whether muscle glycogen remains elevated 3, 5, or 7 days post-supercompensation. Seventeen trained male cyclists underwent one bout of exhaustive exercise to deplete muscle glycogen. This was followed by a 3-day consumption of a high carbohydrate/low protein/low fat diet (85:08:07%). Three post-loading phases followed with subjects randomly assigned to either a 3-day, 5-day, or 7-day post-loading maintenance diet of 60% carbohydrate and limited physical activity. Biopsies (50-150 mg) of the vastus lateralis were obtained pre-load (BASELINE), at peak-load (PEAK), and either at 3-day, 5-day, or 7-day post-load (POST). On average, PEAK to POST muscle glycogen concentrations decreased 34, 20 and 46% respectively for the 3-, 5-, and 7-day POST groups. Only the 7-day post-load group's PEAK to POST mean muscle glycogen concentration decreased significantly. In addition, multi-regression analysis indicated that the PEAK glycogen level was the main determinant of the number of days that glycogen levels remained significantly greater than BASELINE. Thus, trained athletes-supercompensated glycogen levels can remain higher than normal for up to 5 days post-loading. The amount of carbohydrate consumed, the level of physical activity, and the magnitude of the glycogen supercompensation determine the interval for which the glycogen levels are elevated.

Strength training is widely used to increase performance in sports with high physical demands. The use of drugs such as anabolic steroids among athletes is a wellknown phenomenon, and the effects of these drugs on physical performance documented. The studies presented in this thesis focused on the mechanisms of muscle fiber hypertrophy in the vastus lateralis and the trapezius muscles of strength trained elite athletes. The main hypothesis was that the muscle adaptations to strength training and anabolic steroids are muscle specific. Biopsies were obtained from the trapezius and the vastus lateralis from three groups of elite power lifters. Nine used drugs, ten did not and seven had previously used drugs. Six sedentary males served as controls. The biopsies were frozen and cut in serial cross sections. Histological and immunohistochemical staining techniques were used to analyze muscle fiber morphology and pathology. Fiber type distribution, fiber area, myonuclei number and distribution, satellite cell number and proportion of split fibers were counted and compared for the two muscles within and between the groups. The main findings were that: a) Muscle fiber hypertrophy by strength training is further increased by anabolic steroids. b) The number of nuclei per muscle fiber is higher in power lifters using anabolic steroids compared to non-steroids using lifters. c) Among power lifters who have withdrawn from anabolic steroid usage and training for several years, the number of myonuclei, both subsarcolemmal and internal, remains high. d) In active power lifters, anabolic steroids have no further effect on the number of satellite cells per fiber. e) Power lifters have a high proportion of split fibers. High intensity resistance training increases muscle strength and banned substances such as testosterone and anabolic steroids can enhance the training effects. The studies on muscle cell morphology presented in this thesis reveals that anabolic steroids and testosterone increases muscle fiber size and adds more nuclei to the muscle cell. Based on the morphological appearance of muscle sections from doped and nondoped power lifters, we conclude that testosterone and anabolic steroids enhances the hypertrophic effects of training without adding new features. The addition of myonuclei by training and doping appears to be longer lasting in some muscles than in others. The high proportion of split fibers in power lifter is probably due to high mechanical stress. The findings and conclusions in this thesis raise questions regarding relevant suspension times for athletes caught with banned substances in the body.

Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science

In the present study the cross sectional areas of individual muscle fibers were investigated with focus on statistical methodology. This thesis includes data from two studies; Resistance Study and Method Study. The Resistance Study analyzes the effect of exercise by comparing muscle fiber area before and after eight weeks of resistance training. Muscle biopsies from the vastus lateralis muscle were obtained from young male participants. The purpose of the Method Study was to examine the variation between right and left leg. Contrary to previous studies, this thesis focuses on individual data rather than on group-based data, and therefore takes a different approach than the previously published articles. This is proven to be successful since information is lost when analyzing group-wise, as the increase in small muscle fibers did not show when analyzing as a group. The results of the Resistance Study is similar to the results of the Method Study. Means and standard deviations have a wide spread both between subjects and between biopsies taken from the same subject. Inference on the 10th and 90th percentiles shows a positive pattern in the Resistance Study, in the sense that both the smallest and the largest muscle fibers have grown as a result of the resistance training. If muscle fiber area is used as a proxy for training effect, the conclusion is that many people seem to have responded well to the training.

Bakgrund: Det har tidigare undersökts hur muskelaktivering skiljer sig åt vid en unilateral (UL) och bilateral (BL) knäextension och observerats ett så kallat “Bilateral limb deficit” (BLD). Forskning saknas däremot kring hur BLD skiljer sig beroende på styrketräningserfarenhet. Syfte: Undersöka om elektromyografisk amplitud (EMGa) skiljer sig i m. vastus lateralis (VL) vid isokinetisk maximal knäextension mellan träningsgrupp (TrG) och icke-träningsgrupp (i-TrG). Metod: 6 kvinnor och 6 män rekryterades till studien. Studiedeltagarna delades i två grupper där en grupp hade utövat styrketräning regelbundet och den andra inte. EMGa och kraft mättes på deltagarna under en maximal isokinetisk knäextension i dynamometer. 6 mätningar utfördes på såväl dominant ben (DB) som icke-dominant ben (i-DB) vid 6 UL och 3 BL knäextensioner. Variablerna analyserades och jämfördes mellan grupperna. Resultat: Den genomsnittliga procentuella skillnaden i TrG var på DB 0% (±12.9) och på i-DB 0.7% (±10.8). I i-TrG var den genomsnittliga procentuella skillnaden på DB 21.3 (±11.9) och på i-DB 18.8 (±14.7). Den procentuella skillnaden mellan grupperna vid BL jämfört med UL muskelaktivering var signifikant i både DB (p=0.014) och i-DB (p=0.035). Vid BL knäextension jämfört med total UL kraft uppmätte TrG 1.5 % mindre kraft och i-TrG 17.5 % mindre kraft vid BL knäextension jämfört med total UL kraft. Kraftmomentet och EMGa visade stor korrelation (r=0.831, p=0.001). Konklusion: Studiens primära fynd indikerar att styrketräning minskar BLD. Detta har troligen sin grund i neural adaption men bekräftande orsak är oklar.

Made available in DSpace on 2016-06-02T20:18:07Z (GMT). No. of bitstreams: 1 TeseGMS.pdf: 970423 bytes, checksum: fcf1b4de681ac0b5b8a61da7e6f0acae (MD5) Previous issue date: 2006-10-06 / The purpose of this study was to investigate onset, amplitude and ratio of electric activity of the vastus medialis oblique (VMO), vastus lateralis oblique (VLO) and vastus lateralis longus (VLL) muscle and the angle of the knee joint flexion at heel strike during walking on a treadmill. Fifteen subjects without (22-SD3 years) and twelve with patellofemoral pain syndrome (21-SD2 years) participated in this study. The subjects walked on a treadmill without and with inclination of 5 degrees for 10 minutes. Eight strides were analyzed for each situation. An eletrogoniometer was used to verify the knee flexion angle and a footswitch sensor to determinate the beginning and the end of each stride. An eletrogoniometer was used to verify the knee flexion and a footswitch sensor to inform the beginning and the end of each stride. The electric activity was recorded by surface electrodes (Ag/AgCl), an EMG device with 8 channels (EMG System of Brazil) and a software of acquisition data (AqDados 7.02.06). The electromyographic (EMG) data was processed by Matlab software, that calculated the onset timing of the muscles, the integral values of EMG signal and the EMG ratio (VMO:VLO and VMO:VLL). Knee flexion angle was significantly less in the subject with patellofemoral pain syndrome when compared with the subjects of control group. In the patellofemoral pain syndrome subjects, the EMG onset of vastus lateralis longus ocurred before that vastus medialis oblique, in contrast no such differences ocurred in the control group both during walking on a flat surface and on an inclined surface.The EMG activity of vastus lateralis longus muscle was significantly greater during walking in graded treadmill in the subjects with patellofemoral pain syndrome in relation to the subjects of the control group. The results also showed that to the electric activity of the vastus lateralis oblique muscles was always less than the electric activity of the vastus medialis oblique and/or vastus lateralis longus muscle in both groups, regardless condition. Furthermore, VMO:VLL and VMO:VLO activity ratios showed no significant differences between groups and conditions. The results of the present study showed that subjects with patellofemoral pain syndrome decreased the angle of the knee joint flexion, increased the EMG activity of the vastus muscles and presented EMG onset of vastus lateralis longus before that vastus medialis oblique during graded treadmill walking, suggesting that 5º of the inclination would not be safe for treatment for patients with patellofemoral pain syndrome. In addtion, findings showed less electric activity of the vastus lateralis oblique muscle in relation to the other stabilizers of patella, suggesting that vastus medialis oblique and vastus lateralis longus muscles maintain patellar alignment while VLO doesn t act as lateral stabilizer of the patella, but it acts in the dynamics of patellofemoral joint during gait. / O objetivo deste estudo foi investigar o o ângulo de flexão do joelho, o tempo de início da ativação muscular (onset), as relações (VMO:VLO e VMO:VLL) e a amplitude da atividade elétrica dos músculos vasto medial oblíquo (VMO), vasto lateral oblíquo (VLO) e vasto lateral longo (VLL) durante caminhar na esteira. Quinze sujeito sem (22±3 anos) e doze com síndrome de dor femoropatelar (21±2 anos) participaram desse estudo. Os sujeitos caminharam em uma esteira elétrica sem inclinação e com inclinação de 5 graus durante aproximadamente 10 minutos, sendo coletadas 8 passadas em cada situação. Foi utilizado um eletrogoniômetro para verificar o ângulo de flexão do joelho e um sensor tipo footswitch para informar o início e o final de cada passada. A atividade elétrica foi captada por meio de eletrodos de superfície simples diferenciais, um eletromiógrafo de 8 canais (EMG System do Brasil) e um programa de aquisição de dados (AqDados 7.02.06). O sinal elétrico obtido foi tratado por meio de rotinas do software Matlab 6.1 que calcularam o onset e a integral matemática da área abaixo da envoltória do sinal retificado e filtrado (amplitude) e as relações VMO:VLL e VMO:VLO. O ângulo de flexão do joelho foi significativamente menor nos sujeitos com síndrome de dor femoropatelar quando comparado com os sujeitos do grupo controle. A atividade do músculo vasto lateral longo foi significativamente anterior a ativação do músculo vasto medial oblíquo nos sujeitos do grupo com síndrome de dor femoropatelar, enquanto o contrário ocorreu nos sujeitos do grupo controle, independente da condição estudada. A amplitude (integral) da atividade elétrica do músculo vasto lateral longo foi significativamente maior durante o caminhar em superfície inclinada nos sujeitos com síndrome de dor femoropatelar em relação aos sujeitos do grupo controle. Os resultados também mostraram que a a atividade elétrica do músculo vasto lateral oblíquo foi sempre menor que a atividade elétrica do músculo vasto medial oblíquo e/ou vasto lateral longo em ambos os grupos, indiferente da condição (plana e inclinada). Além disso, não foram encontradas diferenças significativas nas relações VMO:VLL e VMO:VLO nas duas condições estudadas e em ambos os grupos. Os resultados do presente estudo mostraram que os sujeitos com síndrome de dor femoropatelar diminuiram o ângulo de flexão do joelho, aumentaram a atividade dos músculos vastos e apresentaram ativação do músculo vasto lateral longo precedendo a do músculo vasto medial oblíquo durante o caminhar em superfície inclinada, sugerindo que 5º de inclinação poderia não ser seguro para o tratamento de sujeitos com essa patologia. Além disso, os achados mostraram menor atividade elétrica do músculo vasto lateral oblíquo em relação aos demais estabilizadores patelares, sugerindo que os músculos vasto medial oblíquo e vasto lateral longo mantém o alinhamento patelar enquanto o VLO não é um estabilizador lateral da patela, mas atua na dinâmica da articulação femoropatelar durante o caminhar.