Submitted by Pedro de Camargo Guizelini null (pedroguizepa@hotmail.com) on 2018-03-14T16:56:07Z No. of bitstreams: 1 Dissertação Pedro Guizelini - Repositorio.pdf: 2007705 bytes, checksum: d596b79d35b56dca87fdf230055fb823 (MD5) / Approved for entry into archive by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br) on 2018-03-14T18:02:51Z (GMT) No. of bitstreams: 1 guizelini_pc_me_rcla.pdf: 1825856 bytes, checksum: ac375acb4fff466e5fdfa4ff2d5c2bf1 (MD5) / Made available in DSpace on 2018-03-14T18:02:51Z (GMT). No. of bitstreams: 1 guizelini_pc_me_rcla.pdf: 1825856 bytes, checksum: ac375acb4fff466e5fdfa4ff2d5c2bf1 (MD5) Previous issue date: 2018-02-28 / A inclinação da curva força-tempo, obtida durante contrações voluntárias explosivas é definida como taxa de desenvolvimento de força (TDF). Como a TDF reflete a capacidade de desenvolver rapidamente força muscular, ela tem sido considerada uma importante ferramenta para a análise de performance desportiva, principalmente em esportes onde contrações explosivas e/ou ações funcionais (locomoção e manutenção do equilíbrio) são necessárias. Vários protocolos de treinamento com diferentes características (intensidade, número de series, número de repetições, duração) têm produzido melhora significante na TDF. Nesses estudos, vários mecanismos fundamentais para a melhora da TDF foram identificados. No entanto, não há clareza sobre os efeitos que diferentes aspectos do treinamento – tais como o tipo de contração, a velocidade da contração, especificidade de posição corporal entre teste e treinamento e a duração do treinamento - têm sobre a melhora da TDF. Sendo assim, esses aspectos continuam elusivos e são necessárias mais evidências. Então, o objetivo deste estudo foi realizar uma revisão sistemática da literatura sobre a influência do treinamento resistido na TDF em adultos. Adicionalmente, o objetivo da presente meta-análise foi investigar, através da meta regressão, os efeitos das variáveis específicas de treinamento: 1) intenção de realizar o movimento de forma explosiva, independente da velocidade; 2) tipo de treinamento; 3) especificidade; 4) duração total do treinamento na TDF. A busca sistemática na literatura foi realizada em bases de dados eletrônicas desde o início até Marco de 2017, e os estudos descrevendo o efeito do treinamento resistido na TDF em adultos saudáveis foram considerados elegíveis. Dezoito estudos relevantes foram incluídos após a revisão sistemática, compreendendo um total de 527 indivíduos saudáveis. O treinamento resistido proporcionou um efeito benéfico moderado na TDF (% mudança = 27,17, 95%LC 18,22 a 36,81, p < 0,001). O treinamento resistido realizado com ações musculares explosivas e alta velocidade de contração (i.e.,treinamento explosivo) teve um efeito superior na melhora da TDF quando comparado ao treinamento isométrico e de força. No entanto, as contrações musculares explosivas realizadas durante o treinamento de força (i.e., alta carga e baixa velocidade) e o treinamento isométrico não parecem ser capazes de induzir a uma maior melhora de TDF do que o treinamento sem contrações musculares explosivas. Assim, até o momento, ainda não é possível se identificar se a elevada TDF contrátil por si só é o principal estímulo do treinamento para a melhora da TDF na fase inicial da contração (i.e., < 100 ms). / The slope of the moment (force)-time curve recorded during explosive voluntary contractions has been defined as the rate of force development (RFD). The RFD can be measured at different time intervals from the onset of the muscle contraction, and has been classified as RFD early (< 100 ms) and RFD late (> 100 ms). Since RFD reflects the capacity to rapidly develop muscle force, it has been considered an important tool for the analysis of sports performance, specifically in explosive-type sports and functional tasks (e.g. locomotion and postural balance). Several training protocols with different characteristics (intensity, number of sets, number of repetitions, duration) have produced significant improvement in RFD. In these studies, mechanisms have been identified that are important for RFD enhancement after different resistance training protocols. However, there is no clarity about the effects of different training variables – such as contraction type, contraction speed, body position specificity between training and testing and training duration – on RFD. Therefore, these aspects remain elusive and more data is needed. Thus, the purpose of the present systematic review and meta-analysis is to determine the general effects of resistance training on RFD in adults. Furthermore, the present meta-analysis, using meta-regression, examines how specific training variables, such as: 1) intention of performing explosive muscle actions irrespective of high velocity movements; 2) training type; 3) specificity; and 4) total training duration affect RFD. A systematic literature search on electronic databases was performed up to March 2017, and the studies describing the resistance training effect on RFD in healthy adults were considered eligible. Eighteen relevant studies were included after systematic review, comprehending a total of 527 healthy individuals. Resistance training yielded a moderate beneficial effect on RFD (% change = 27,17, 95%CI 18,22 to 36,81, p < 0,001). Resistance training performed with explosive muscle actions and high contraction velocity (i.e., explosive training) had a superior effect on RFD improvement, when compared to isometric and strength training. However, explosive muscle contractions performed during strength training (i.e., high loads and low velocity) and isometric training don’t seem to be able to induce a higher RFD improvement when compared to training without explosive muscle contractions. Thus, the actual data does not allow identifying the high contractile RFD per se, as the main training stimulus for early RFD enhancement. (i.e., < 100 ms).

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Muskeln oszillieren nachgewiesener Weise mit einer Frequenz um 10 Hz. Doch was geschieht mit myofaszialen Oszillationen, wenn zwei neuromuskuläre Systeme interagieren? Die Dissertation widmet sich dieser Fragestellung bei isometrischer Interaktion. Während der Testmessungen ergaben sich Hinweise für das Vorhandensein von möglicherweise zwei verschiedenen Formen der Isometrie. Arbeiten zwei Personen isometrisch gegeneinander, können subjektiv zwei Modi eingenommen werden: man kann entweder isometrisch halten – der Kraft des Partners widerstehen – oder isometrisch drücken – gegen den isometrischen Widerstand des Partners arbeiten. Daher wurde zusätzlich zu den Messungen zur Interaktion zweier Personen an einzelnen Individuen geprüft, ob möglicherweise zwei Formen der Isometrie existieren. Die Promotion besteht demnach aus zwei inhaltlich und methodisch getrennten Teilen: I „Single-Isometrie“ und II „Paar-Isometrie“. Für Teil I wurden mithilfe eines pneumatisch betriebenen Systems die hypothetischen Messmodi Halten und Drücken während isometrischer Aktion untersucht. Bei n = 10 Probanden erfolgte parallel zur Aufzeichnung des Drucksignals während der Messungen die Erfassung der Kraft (DMS) und der Beschleunigung sowie die Aufnahme der mechanischen Muskeloszillationen folgender myotendinöser Strukturen via Mechanomyo- (MMG) bzw. Mechanotendografie (MTG): M. triceps brachii (MMGtri), Trizepssehne (MTGtri), M. obliquus externus abdominis (MMGobl). Pro Proband wurden bei 80 % der MVC sowohl sechs 15-Sekunden-Messungen (jeweils drei im haltenden bzw. drückenden Modus; Pause: 1 Minute) als auch vier Ermüdungsmessungen (jeweils zwei im haltenden bzw. drückenden Modus; Pause: 2 Minuten) durchgeführt. Zum Vergleich der Messmodi Halten und Drücken wurden die Amplituden der myofaszialen Oszillationen sowie die Kraftausdauer herangezogen. Signifikante Unterschiede zwischen dem haltenden und dem drückenden Modus zeigten sich insbesondere im Bereich der Ermüdungscharakteristik. So lassen Probanden im haltenden Modus signifikant früher nach als im drückenden Modus (t(9) = 3,716; p = .005). Im drückenden Modus macht das längste isometrische Plateau durchschnittlich 59,4 % der Gesamtdauer aus, im haltenden sind es 31,6 % (t(19) = 5,265, p = .000). Die Amplituden der Single-Isometrie-Messungen unterscheiden sich nicht signifikant. Allerdings variieren die Amplituden des MMGobl zwischen den Messungen im drückenden Modus signifikant stärker als im haltenden Modus. Aufgrund dieser teils signifikanten Unterschiede zwischen den beiden Messmodi wurde dieses Setting auch im zweiten Teil „Paar-Isometrie“ berücksichtigt. Dort wurden n = 20 Probanden – eingeteilt in zehn gleichgeschlechtliche Paare – während isometrischer Interaktion untersucht. Die Sensorplatzierung erfolgte analog zu Teil I. Die Oszillationen der erfassten MTG- sowie MMG-Signale wurden u.a. mit Algorithmen der Nichtlinearen Dynamik auf ihre Kohärenz hin untersucht. Durch die Paar-Isometrie-Messungen zeigte sich, dass die Muskeln und die Sehnen beider neuromuskulärer Systeme bei Interaktion im bekannten Frequenzbereich von 10 Hz oszillieren. Außerdem waren sie in der Lage, sich bei Interaktion so aufeinander abzustimmen, dass sich eine signifikante Kohärenz entwickelte, die sich von Zufallspaarungen signifikant unterscheidet (Patchanzahl: t(29) = 3,477; p = .002; Summe der 4 längsten Patches: t(29) = 7,505; p = .000). Es wird der Schluss gezogen, dass neuromuskuläre Komplementärpartner in der Lage sind, sich im Sinne kohärenten Verhaltens zu synchronisieren. Bezüglich der Parameter zur Untersuchung der möglicherweise vorhandenen zwei Formen der Isometrie zeigte sich bei den Paar-Isometrie-Messungen zwischen Halten und Drücken ein signifikanter Unterschied bei der Ermüdungscharakteristik sowie bezüglich der Amplitude der MMGobl. Die Ergebnisse beider Teilstudien bestärken die Hypothese, dass zwei Formen der Isometrie existieren. Fraglich ist, ob man überhaupt von Isometrie sprechen kann, da jede isometrische Muskelaktion aus feinen Oszillationen besteht, die eine per Definition postulierte Isometrie ausschließen. Es wird der Vorschlag unterbreitet, die Isometrie durch den Begriff der Homöometrie auszutauschen. Die Ergebnisse der Paar-Isometrie-Messungen zeigen u.a., dass neuromuskuläre Systeme in der Lage sind, ihre myotendinösen Oszillationen so aufeinander abzustimmen, dass kohärentes Verhalten entsteht. Es wird angenommen, dass hierzu beide neuromuskulären Systeme funktionell intakt sein müssen. Das Verfahren könnte für die Diagnostik funktioneller Störungen relevant werden. / Muscles oscillate with a frequency of about 10 Hz. But what happens with myofascial oscillations if two neuromuscular systems interact? The dissertation is devoted to this question during isometric interaction. The test measurements provide hints for the presence of possibly two different forms of isometric muscle action. When two persons work against each other, each individual can subjectively choose to take up one of two modes: one can either hold isometrically – thus resist the force of the partner – or one can push isometrically – and therefore work against the resistance of the partner. In addition to the measurements to determine the interaction of neuromuscular systems, measurements with single individuals were done to evaluate the question, if probably two forms of isometric muscle action exist. The doctoral thesis consists of two separate parts concerning the content and methodology: I “Single Isometric” and II “Coupled Isometric”. For part I the hypothetical measurement modes - “holding” and “pushing” during isometric muscle action - were examined using a pneumatic system. During the measurements of n = 10 subjects the signal of pressure, force (strain gauge) and acceleration were recorded. Furthermore, the detection of the mechanic muscle oscillations of the following myotendinal structures occurred via Mechanomyo- (MMG) and Mechanotendography (MTG), respectively: triceps brachii muscle (MMGtri), tendon of triceps brachii muscle (MTGtri) and obliquus externus abdominis muscle (MMGobl). Each test person performed at 80 % of MVC six 15-seconds-measurements (three at holding and three at pushing mode, respectively; break: 1 min.) as well as four fatigue measurements (two at holding and two at pushing mode, respectively; break: 2 min.). In order to compare the two measurement modes holding and pushing, the amplitude of the myofascial oscillations as well as the force endurance were used. Significant differences between the holding and the pushing mode appeared especially when looking at the characteristics of fatigue. Subjects in the holding mode yielded earlier than during the pushing one (t(9) = 3.716; p = .005). In the pushing mode the longest isometric plateau amounts 59.4 % of the overall duration of the measurement. During holding it lasted 31.6 % (t(19) = 5.265, p = .000). The amplitudes of the single-isometric-measurements did not differ significantly. But the amplitude of the MMGobl varied significantly stronger during the pushing mode comparing to the holding one. Due to these partly significant differences between both measurement modes, this setting was considered for the second part „Coupled-Isometric“, too. For the coupled-isometric-measurements n = 20 subjects – divided into same-sex couples – were investigated during isometric interaction. The placement of the sensors is analogous to part I. The oscillations of the recorded MMG- and MTG-signals were analyzed regarding their coherence inter alia by algorithms of non-linear dynamics. Through the coupled-isometric-measurements it was shown, that also during isometric interaction the muscles and the tendons of both neuromuscular systems oscillate at the known frequency range of 10 Hz. Moreover, the systems are able to coordinate them in such a manner, that a significant coherence appears. This differed significantly from random pairings (number of patches: t(29) = 3.477; p = .002; Sum of 4 longest patches: t(29) = 7.505; p = .000). Thus it is concluded that neuromuscular complementary partners are able to synchronize themselves in the sense of coherent behavior. Regarding the parameters concerning the possibly existing forms of isometric muscle action, a significant difference at the coupled-isometric-measurements between holding and pushing appeared with respect to the characteristics of fatigue as well as the amplitudes of the MMGobl. The results of both sub studies strengthen the hypothesis that two forms of isometric muscle action exist. It is questionable whether one can talk of isometry at all, since each isometric muscle action consists of fine oscillations. This excludes a by definition postulated isometry. It is proposed to exchange this term with homeometry. The results of the coupled-isometric-measurements show inter alia, that neuromuscular systems are able to coordinate their myotendinal oscillations, so that coherent behavior arises. It is supposed that for this both systems have to be functionally intact. This procedure could become relevant for diagnostics of functional disorders.

The presented work is concerned with the development and application of an ultrasonic detection scheme suitable for the monitoring of muscle dynamics with high temporal - down to 5 µs - and spatial resolution - down to 0.78 µm. A differential detection scheme has been developed to monitor the variations of the velocity of longitudinal polarized ultrasound waves travelling in contracting and relaxing muscle, compensating for variations of the path length by referencing to a frame. The observed time dependent variations of the time-of-flight of the ultrasonic waves caused by variations in the muscle and in addition by minor deformations of the enclosure are detected each separately and synchronously and are evaluated differentially. Beside of the detected increase of the speed of sound observed for contracted muscle with respect to the relaxed state of about 0.6%, the recovery time from maximum isometric contraction is quantified and relaxation processes are observed for the recovery phase following the isometric contraction. The developed ultrasonic calliper was employed to monitor both, the brain controlled and externally excited muscle dynamics with sampling intervals down to 10 ms synchronously with signals relating to the excitation. Monitored are the activation, hold, and relaxation phase for maximum voluntary isometric contraction of the gastrocnemius muscle. A so far not reported post tetanus overshoot and subsequent exponential recovery are observed. Both are attributed to the muscle as suggested by combined monitoring with EMG and are modelled with a lumped mechanical circuit containing an idealized bidirectional linear motor unit, ratchet, damper, and springs. Both, the rapid contraction and relaxation phases require a high order filter or alternatively a kernel filter, attributed to the nerve system as suggested by external electric stimulation. The respective response function is modelled by an electrical lumped circuit. Together with a reaction time and occasionally observed droops in the hold phase, both adjusted empirically, the monitored response is represented in close approximation by the combined electrical and mechanical lumped circuits. The respectively determined model parameters provide a refined evaluation scheme for the performance of monitored athletes. Valuable parameters relate to the latent period, the muscle response time, the activation and deactivation dynamics, a possible droop and other instabilities of the hold phase, and parameters characterizing the relaxation phase including the observed post tetanus overshoot and subsequent contraction. Monitored and modelled are also the different processes involved in active muscle dynamics including isotonic, isometric, and eccentric contraction or stretching. The developed technology provides time sequential observation of these processes and registration of their path in the extension and force parameter space. Under suitable conditions the closed-loop cycles of mind controlled human muscle movements proceed along characteristic lines coinciding with well identifiable elementary processes. The presentation of the monitored processes in the extension and force parameter space allows the determination of the mechanical energy expenditure for the observed different muscle actions. An elementary macroscopic mechanical model has been developed, suitable to express the basic features of the monitored muscle dynamics.

The presented work is concerned with the development and application of an ultrasonic detection scheme suitable for the monitoring of muscle dynamics with high temporal - down to 5 µs - and spatial resolution - down to 0.78 µm. A differential detection scheme has been developed to monitor the variations of the velocity of longitudinal polarized ultrasound waves travelling in contracting and relaxing muscle, compensating for variations of the path length by referencing to a frame. The observed time dependent variations of the time-of-flight of the ultrasonic waves caused by variations in the muscle and in addition by minor deformations of the enclosure are detected each separately and synchronously and are evaluated differentially. Beside of the detected increase of the speed of sound observed for contracted muscle with respect to the relaxed state of about 0.6%, the recovery time from maximum isometric contraction is quantified and relaxation processes are observed for the recovery phase following the isometric contraction. The developed ultrasonic calliper was employed to monitor both, the brain controlled and externally excited muscle dynamics with sampling intervals down to 10 ms synchronously with signals relating to the excitation. Monitored are the activation, hold, and relaxation phase for maximum voluntary isometric contraction of the gastrocnemius muscle. A so far not reported post tetanus overshoot and subsequent exponential recovery are observed. Both are attributed to the muscle as suggested by combined monitoring with EMG and are modelled with a lumped mechanical circuit containing an idealized bidirectional linear motor unit, ratchet, damper, and springs. Both, the rapid contraction and relaxation phases require a high order filter or alternatively a kernel filter, attributed to the nerve system as suggested by external electric stimulation. The respective response function is modelled by an electrical lumped circuit. Together with a reaction time and occasionally observed droops in the hold phase, both adjusted empirically, the monitored response is represented in close approximation by the combined electrical and mechanical lumped circuits. The respectively determined model parameters provide a refined evaluation scheme for the performance of monitored athletes. Valuable parameters relate to the latent period, the muscle response time, the activation and deactivation dynamics, a possible droop and other instabilities of the hold phase, and parameters characterizing the relaxation phase including the observed post tetanus overshoot and subsequent contraction. Monitored and modelled are also the different processes involved in active muscle dynamics including isotonic, isometric, and eccentric contraction or stretching. The developed technology provides time sequential observation of these processes and registration of their path in the extension and force parameter space. Under suitable conditions the closed-loop cycles of mind controlled human muscle movements proceed along characteristic lines coinciding with well identifiable elementary processes. The presentation of the monitored processes in the extension and force parameter space allows the determination of the mechanical energy expenditure for the observed different muscle actions. An elementary macroscopic mechanical model has been developed, suitable to express the basic features of the monitored muscle dynamics.:Table of Contents Chapter 1 1. Introduction 1 1.1 Monitoring of muscle biomechanics 1 1.2 Detection methods in biomechanics 2 1.3 Ultrasound in biomechanical application 5 1.4 Skeletal muscle 6 1.5 Activation of skeletal muscle 8 1.6 Catatonus effect 10 Chapter 2 2. Concepts and methods in ultrasonic motion monitoring 12 2.1 Ultrasound 12 2.2 Specific concepts of the developed ultrasonic detection scheme 16 2.2.1 Time-of-flight 17 2.2.2 Cross correlation 18 2.2.3 Concepts of cross correlation 19 2.2.4 Chirp technique 19 Chapter 3 3. Ultrasonic monitoring of the muscle extension 21 3.1 Data analysis 21 3.2 Application of the developed monitoring scheme 23 3.2.1 Fast signal and data acquisition mode 23 3.2.2 Monitoring with off-line evaluation 24 3.2.3 Method 26 3.2.4 Data evaluation 27 3.3 Quasi-continuous monitoring scheme 28 3.3.1 Slow with on-line data processing and display 29 3.3.2 Fast with data storage only 30 3.4 Monitoring with on-line evaluation 34 3.4.1 Application involving monitoring of athletic performance 36 3.4.2 Data evaluation 37 3.4.3 Summary 42 3.5 Comparative study of pre and post physical loading session 43 3.5.1 Method 43 3.5.2 Results 44 3.5.3 Summary 45 Chapter 4 4. High resolution monitoring of the velocity of ultrasound in contracting and relaxing muscle 47 4.1 Methods 49 4.2 Results and evaluation 51 4.2.1 Poission’s ratio for isometrically contracted muscle 52 4.3 Summary 53 Chapter 5 5. Monitoring of muscle dynamics, muscle force, and EMG 56 5.1 Synchronous monitoring of muscle dynamics with muscle force 56 5.1.1 Force-length dynamics under all-out isometric contraction 56 5.1.1.1 Method 56 5.1.1.2 Result and evaluation 58 5.1.2 Force-length dynamics of equal holding monitoring 62 5.1.2.1 Method 62 5.1.2.2 Results and evaluation 63 5.1.3 Summary 67 5.2 Synchronous monitoring of muscle movement with EMG 69 5.2.1 Method 69 5.2.2 Results and evaluation 70 5.3 Synchronous monitoring of muscle movement, EMG and muscle force 73 5.3.1 Method 73 5.3.2 Results and evaluation 74 5.3.3 Summary 77 Chapter 6 6. Monitoring of skeletal muscle dynamics under isometric contraction and modelling of the non-linear response including post tetanus effects 80 6.1 Method 82 6.2 Data analysis 82 6.3 Results and evaluation 82 6.3.1 Mechanical model 83 6.3.2 Equations relating to modelling 85 6.3.3 Comparison of experimental results and modelling 91 6.3.4 Electrical lumped circuit 93 6.4 Summary 100 Chapter 7 7. Lumped Circuit Model and Energy Transfer for quasi-static approximation 101 7.1 Basic muscle model and biomechanical processes 102 7.1.1 Muscle model 102 7.1.2 Force in the muscular motoric processes 104 7.2 Method 104 7.3 Results of experimental observations of muscle action 106 7.3.1 Muscle force and closed-loop contraction dynamics 106 7.3.2 Muscle work considerations 109 7.4 Summary 110 Chapter 8 8.1 Ultrasonic calliper 112 8.2 Interpretation of sound velocity variation in muscle 114 8.3 Monitored muscle dynamics 118 8.4 Isometric muscle action and tetanus effect 121 8.5 Quasi-static muscle action 125 8.6 Summarizing statement with a moderate outlook 126 References 128 Acknowledgements 140 Selbständigkeitserklärung 141