TY - GEN A1 - Engel, Tilman A1 - Schraplau, Anne A1 - Wochatz, Monique A1 - Kopinski, Stephan A1 - Sonnenburg, Dominik A1 - Schomöller, Anne A1 - Risch, Lucie A1 - Kaplick, Hannes A1 - Mayer, Frank T1 - Feasability of An Eccentric Isokinetic Protocol to Induce Trunk Muscle Damage: A Pilot Study T2 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Eccentric exercise is discussed as a treatment option for clinical populations, but specific responses in terms of muscle damage and systemic inflammation after repeated loading of large muscle groups have not been conclusively characterized. Therefore, this study tested the feasibility of an isokinetic protocol for repeated maximum eccentric loading of the trunk muscles. Nine asymptomatic participants (5 f/4 m; 34±6 yrs; 175±13 cm; 76±17 kg) performed three isokinetic 2-minute all-out trunk strength tests (1x concentric (CON), 2x eccentric (ECC1, ECC2), 2 weeks apart; flexion/extension, 60°/s, ROM 55°). Outcomes were peak torque, torque decline, total work, and indicators of muscle damage and inflammation (over 168 h). Statistics were done using the Friedman test (Dunn’s post-test). For ECC1 and ECC2, peak torque and total work were increased and torque decline reduced compared to CON. Repeated ECC bouts yielded unaltered torque and work outcomes. Muscle damage markers were highest after ECC1 (soreness 48 h, creatine kinase 72 h; p<0.05). Their overall responses (area under the curve) were abolished post-ECC2 compared to post-ECC1 (p<0.05). Interleukin-6 was higher post-ECC1 than CON, and attenuated post-ECC2 (p>0.05). Interleukin-10 and tumor necrosis factor-α were not detectable. All markers showed high inter-individual variability. The protocol was feasible to induce muscle damage indicators after exercising a large muscle group, but the pilot results indicated only weak systemic inflammatory responses in asymptomatic adults. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 773 KW - exercise KW - eccentric KW - muscle fatigue KW - trunk muscles KW - isokinetics KW - repeated bout effect KW - inflammation KW - exercise induced muscle damage KW - interleukin-6 KW - internleukin-10 KW - tumor necrosis factor-α Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-557409 SN - 1866-8364 SP - E9 EP - E17 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Engel, Tilman A1 - Schraplau, Anne A1 - Wochatz, Monique A1 - Kopinski, Stephan A1 - Sonnenburg, Dominik A1 - Schomöller, Anne A1 - Risch, Lucie A1 - Kaplick, Hannes A1 - Mayer, Frank T1 - Feasability of An Eccentric Isokinetic Protocol to Induce Trunk Muscle Damage: A Pilot Study JF - Sports Medicine International Open N2 - Eccentric exercise is discussed as a treatment option for clinical populations, but specific responses in terms of muscle damage and systemic inflammation after repeated loading of large muscle groups have not been conclusively characterized. Therefore, this study tested the feasibility of an isokinetic protocol for repeated maximum eccentric loading of the trunk muscles. Nine asymptomatic participants (5 f/4 m; 34±6 yrs; 175±13 cm; 76±17 kg) performed three isokinetic 2-minute all-out trunk strength tests (1x concentric (CON), 2x eccentric (ECC1, ECC2), 2 weeks apart; flexion/extension, 60°/s, ROM 55°). Outcomes were peak torque, torque decline, total work, and indicators of muscle damage and inflammation (over 168 h). Statistics were done using the Friedman test (Dunn’s post-test). For ECC1 and ECC2, peak torque and total work were increased and torque decline reduced compared to CON. Repeated ECC bouts yielded unaltered torque and work outcomes. Muscle damage markers were highest after ECC1 (soreness 48 h, creatine kinase 72 h; p<0.05). Their overall responses (area under the curve) were abolished post-ECC2 compared to post-ECC1 (p<0.05). Interleukin-6 was higher post-ECC1 than CON, and attenuated post-ECC2 (p>0.05). Interleukin-10 and tumor necrosis factor-α were not detectable. All markers showed high inter-individual variability. The protocol was feasible to induce muscle damage indicators after exercising a large muscle group, but the pilot results indicated only weak systemic inflammatory responses in asymptomatic adults. KW - exercise KW - eccentric KW - muscle fatigue KW - trunk muscles KW - isokinetics KW - repeated bout effect KW - inflammation KW - exercise induced muscle damage KW - interleukin-6 KW - internleukin-10 KW - tumor necrosis factor-α Y1 - 2021 U6 - https://doi.org/10.1055/a-1757-6724 SN - 2367-1890 VL - 6 SP - E9 EP - E17 PB - Thieme CY - Stuttgart ET - 1 ER - TY - THES A1 - Wochatz, Monique T1 - Influence of different loading conditions on scapular movement and scapular muscle activation patterns T1 - Der Einfluss verschiedener Lastsituationen auf Bewegungs- und Aktivitätsmuster des Schulterblatts N2 - The scapula plays a significant role in efficient shoulder movement. Thus, alterations from typical scapular motion during upper limb movements are thought to be associated with shoulder pathologies. However, a clear understanding of the relationship is not yet obtained.. Scapular alterations may only represent physiological variability as their occurrence can appear equally as frequent in individuals with and without shoulder disorders. Evaluation of scapular motion during increased load might be a beneficial approach to detect clinically relevant alterations. However, functional motion adaptations in response to maximum effort upper extremity loading has not been established yet. Therefore, the overall purpose of this research project was to give further insight in physiological adaptations of scapular kinematics and their underlying scapular muscle activity in response to high demanding shoulder movements in healthy asymptomatic individuals. Prior to the investigation of the effect of various load situation, the reproducibility of scapular kinematics and scapular muscle activity were evaluated under maximum effort arm movements. Healthy asymptomatic adults performed unloaded and maximal loaded concentric and eccentric isokinetic shoulder flexion and extension movements in the scapular plane while scapular kinematics and scapular muscle activity were simultaneously assessed. A 3D motion capture system (infra-red cameras & reflective markers) was utilized to track scapular and humerus motion in relation to the thorax. 3D scapular position angles were given for arm raising and lowering between humerus positions of 20° and 120° flexion. To further characterize the scapular pattern, the scapular motion extent and scapulohumeral rhythm (ratio of scapular and humerus motion extent) were determined. Muscle activity of the upper and lower trapezius and the serratus anterior were assessed with surface electromyography. Amplitudes were calculated for the whole ROM and four equidistant movement phases. Reliability was characterized by overall moderate to good reproducibility across the load conditions. Irrespective of applied load, scapular kinematics followed a motion pattern of continuous upward rotation, posterior tilt and external rotation during arm elevation and a continuous downward rotation, anterior tilt and internal rotation during arm lowering. However, kinematics were altered between maximal loaded and unloaded conditions showing increased upward rotation, reduced posterior tilt and external rotation. Further, the scapulohumeral rhythm was decreased and scapular motion extent increased under maximal loaded movements. Muscle activity during maximum effort were of greater magnitude and differed in their pattern in comparison to the continuous increase and decrease of activity during unloaded shoulder flexion and extension. Relationships between scapular kinematics and their underlying scapular muscle activity could only be identified for a few isolated combinations, whereas the majority showed no associations. Scapular kinematics and scapular muscle activity pattern alter according to the applied load. Alterations between the load conditions comply in magnitude and partially in direction with differences seen between symptomatic and asymptomatic individuals. Even though long-term effects of identified adaptations in response to maximum load are so far unclear, deviations from typical scapular motion or muscle activation should not per se be seen as indicators of shoulder impairment. However, evaluation of alterations in scapular motion and activation in response to maximum effort may have the potential to identify individuals that are unable to cope with increased upper limb demands. Findings further challenge the understanding of scapular motion and stabilization by the trapezius and serratus anterior muscles, as clear relationships between the underlying scapular muscle activity and scapular kinematics were neither observed during unloaded nor maximal loaded shoulder movements. N2 - Das Schulterblatt ist entscheidend für die uneingeschränkte Bewegung und Positionierung der oberen Extremität. Atypische Bewegungsmuster des Schulterblatts werden deshalb oft mit Schulterpathologien in Verbindung gebracht, obwohl die zugrundeliegenden Mechanismen noch nicht ausreichend geklärt sind. Abweichungen stellen möglicherweise nur eine Form physiologischer Variabilität dar, da Veränderungen der Schulterblattbewegung sowohl bei Personen mit als auch ohne Schulterbeschwerden auftreten können. Die Beurteilung der Schulterblattbewegung unter erhöhten Lastbedingungen könnte hilfreich bei der Differenzierung von funktionellen und klinisch relevanten Veränderungen sein. Jedoch sind physiologische Anpassungen der Schulterblattkinematik in Reaktion auf maximale Anforderungen während einer Bewegungsaufgabe der oberen Extremität bisher nicht untersucht. Das Ziel dieses Forschungsprojektes war es deshalb weitere Erkenntnisse hinsichtlich physiologischer Anpassungen der Schulterblattkinematik und ihrer zugrundeliegenden Muskelaktivität zu erlangen. Bevor die Effekte verschiedener Belastungssituationen untersucht wurden, erfolgte die Beurteilung der Reproduzierbarkeit der Schulterblattkinematik sowie der Aktivitätslevel schulterblattstabilisierender Muskeln unter maximaler Anstrengung. Gesunde asymptomatische Erwachsene führten isokinetische Schulterbewegungen in Flexion und Extension unter unbelasteten sowie maximal belasteten Bedingungen durch. Zeitgleich wurde die Schulterblattkinematik sowie die Aktivität schulterstabilisierender Muskeln erfasst. Mit Hilfe eines 3D Kamera Systems (Infrarotkameras & reflektierende Marker) wurden Winkelpositionen des Schulterblatts für Humerus-Positionen zwischen 20° und 120° Flexion bestimmt. Zur weiteren Charakterisierung der Schulterblattbewegung wurde das Ausmaß der Schulterblattrotation sowie der skapulohumerale Rhythmus (Verhältnis von Schulterblatt- und Humerus-Bewegung) ermittelt. Während der Schulterbewegungen wurde die Muskelaktivität des oberen und unteren Trapezius sowie des Serratus anterior mit Oberflächen-Elektromyographie erfasst. Aktivitätslevel wurden für das gesamte Bewegungsausmaß sowie für einzelne Bewegungsphasen berechnet. Eine moderate bis gute Reproduzierbarkeit der Winkelpositionen des Schulterblatts sowie der Aktivitätslevel der schulterblattstabilisierenden Muskulatur konnte unter den verschiedenen Lastbedingungen erreicht werden. Unabhängig von der applizierten Last folgte das Schulterblatt einer kontinuierlichen Aufwärtsrotation, Rückwärtsneigung und Außenrotation während der Schulterflexion und einer kontinuierlichen Abwärtsrotation, Vorwärtsneigung und Innenrotation während der Schulterextension. Bei maximalen Belastungen zeigte das Schulterblatt jedoch eine gesteigerte Aufwärtsrotation sowie eine verringerte Rückwärtsneigung und Außenrotation im Vergleich zur unbelasteten Schulterbewegung. Der skapulohumerale Rhythmus verringerte sich und auch das Ausmaß der Schulterblattrotation war unter maximaler Last erhöht. Die Muskelaktivität zeigte sich unter maximaler Anstrengung nicht nur im Ausmaß gesteigert sondern wies auch ein verändertes Aktivitätsmuster im Verlauf der Bewegungen im Vergleich zur kontinuierlichen Zu- und Abnahme der Aktivität während unbelasteter Bedingungen auf. Korrelationen zwischen dem Ausmaß der Schulterblattrotation und dem Aktivitätslevel der Schulterblattmuskulatur konnten nur für einige wenige isolierte Kombinationen identifiziert werden, während die Mehrheit keine Assoziationen zeigte. Die Kinematik des Schulterblatts und die Aktivitätsmuster der Schulterblattmuskulatur ändern sich in Abhängigkeit der Belastung. Veränderungen der Kinematik und Aktivitätsmuster entsprechen dabei im Ausmaß und teilweise in der Ausrichtung den bekannten Unterschieden zwischen symptomatischen und asymptomatischen Populationen. Obwohl die langfristigen Auswirkungen dieser veränderten Schulterblattkinematik unter maximalen Belastungen bislang unklar sind, sollten Abweichungen von der typischen Bewegung des Schulterblatts sowie bekannter Aktivitätsmuster per se nicht als Indikatoren für eine Beeinträchtigung der Schulterfunktion angesehen werden. Dennoch könnten Untersuchungen der Schulterblattkinematik sowie der Aktivität schulterblattrotierender und –stabilisierender Muskeln unter erhöhten Anforderungen Personen identifizieren die aufgrund mangelnder Anpassung die gesteigerten Lasten nicht kompensieren können. Ein klares Zusammenspiel von Schulterblattkinematik und rotierender sowie stabilisierender Schulterblattmuskulatur ließ sich weder unter unbelasteten noch maximal belasteten Bedingungen aufzeigen. KW - scapular kinematics KW - 3D motion analysis KW - scapular muscles KW - electromyography KW - Schulterblattkinematik KW - 3D-Bewegungsanalyse KW - Schulterblattmuskulatur KW - Elektromyografie Y1 - 2021 ER - TY - JOUR A1 - Schomöller, Anne A1 - Risch, Lucie A1 - Kaplick, Hannes A1 - Wochatz, Monique A1 - Engel, Tilman A1 - Schraplau, Anne A1 - Sonnenburg, Dominik A1 - Huppertz, Alexander A1 - Mayer, Frank T1 - Inter-rater and inter-session reliability of lumbar paraspinal muscle composition in a mobile MRI device JF - BJR : an international journal of radiology, radiation oncology and all related sciences / British Institute of Radiology N2 - Objective: To assess the reliability of measurements of paraspinal muscle transverse relaxation times (T2 times) between two observers and within one observer on different time points.
Methods: 14 participants (9f/5m, 33 +/- 5 years, 176 +/- 10 cm, 73 +/- 12 kg) underwent 2 consecutive MRI scans (M1,M2) on the same day, followed by 1 MRI scan 13-14 days later (M3) in a mobile 1.5 Tesla MRI. T2 times were calculated in T-2 weighted turbo spin- echo-sequences at the spinal level of the third lumbar vertebrae (11 slices, 2 mm slice thickness, 1 mm interslice gap, echo times: 20, 40, 60, 80, 100 ms) for M. erector spinae (ES) and M. multifidius (MF). The following reliability parameter were calculated for the agreement of T2 times between two different investigators (OBS1 & OBS2) on the same MRI (inter rater reliability, IR) and by one investigator between different MRI of the same participant (intersession variability, IS): Test-Retest Variability (TRV, Differences/Mean*100); Coefficient of Variation (CV, Standard deviation/Mean*100); Bland-Altman Analysis (systematic bias = Mean of the Differences; Upper/Lower Limits of Agreement = Bias+/-1.96*SD); Intraclass Correlation Coefficient 3.1 (ICC) with absolute agreement, as well as its 95% confidence interval.
Results: Mean TRV for IR was 2.6% for ES and 4.2% for MF. Mean TRV for IS was 3.5% (ES) and 5.1% (MF). Mean CV for IR was 1.9 (ES) and 3.0 (MF). Mean CV for IS was 2.5% (ES) and 3.6% (MF). A systematic bias of 1.3 ms (ES) and 2.1 ms (MF) were detected for IR and a systematic bias of 0.4 ms (ES) and 0.07 ms (MF) for IS. ICC for IR was 0.94 (ES) and 0.87 (MF). ICC for IS was 0.88 (ES) and 0.82 (MF).
Conclusion: Reliable assessment of paraspinal muscle T2 time justifies its use for scientific purposes. The applied technique could be recommended to use for future studies that aim to assess changes of T2 times, e.g. after an intense bout of eccentric exercises. Y1 - 2021 U6 - https://doi.org/10.1259/bjr.20210141 SN - 0007-1285 SN - 1748-880X VL - 94 IS - 1127 PB - Wiley CY - Bognor Regis ER - TY - JOUR A1 - Wochatz, Monique A1 - Rabe, Sophie A1 - Engel, Tilman A1 - Müller, Steffen A1 - Mayer, Frank T1 - Scapular kinematics during unloaded and maximal loaded isokinetic concentric and eccentric shoulder flexion and extension movements JF - Journal of electromyography & kinesiology : official journal of the International Society of Electrophysiology and Kinesiology N2 - Characterization of scapular kinematics under demanding load conditions might aid to distinguish between physiological and clinically relevant alterations. Previous investigations focused only on submaximal external load situations. How scapular movement changes with maximal load remains unclear. Therefore, the present study aimed to evaluate 3D scapular kinematics during unloaded and maximal loaded shoulder flexion and extension. Twelve asymptomatic individuals performed shoulder flexion and extension movements under unloaded and maximal concentric and eccentric loaded isokinetic conditions. 3D scapular kinematics assessed with a motion capture system was analyzed for 20° intervals of humeral positions from 20° to 120° flexion. Repeated measures ANOVAs were used to evaluate kinematic differences between load conditions for scapular position angles, scapulohumeral rhythm and scapular motion extent. Increased scapular upward rotation was seen during shoulder flexion and extension as well as decreased posterior tilt and external rotation during eccentric and concentric arm descents of maximal loaded compared to unloaded conditions. Load effects were further seen for the scapulohumeral rhythm with greater scapular involvement at lower humeral positions and increased scapular motion extent under maximal loaded shoulder movements. With maximal load applied to the arm physiological scapular movement pattern are induced that may imply both impingement sparing and causing mechanisms. KW - Isokinetics KW - Motion analysis KW - Scapular dyskinesis KW - Scapulohumeral rhythm KW - Scapulothoracic Y1 - 2020 U6 - https://doi.org/10.1016/j.jelekin.2021.102517 SN - 1050-6411 SN - 1873-5711 VL - 57 PB - Elsevier CY - Amsterdam ER -