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 - 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 -
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 -