TY - JOUR
A1 - Lin, Chiao-I
A1 - Khajooei, Mina
A1 - Engel, Tilman
A1 - Nair, Alexandra
A1 - Heikkila, Mika
A1 - Kaplick, Hannes
A1 - Mayer, Frank
T1 - The effect of chronic ankle instability on muscle activations in lower extremities
JF - PLOS ONE / Public Library of Science
N2 - Background/Purpose
Muscular reflex responses of the lower extremities to sudden gait disturbances are related to postural stability and injury risk. Chronic ankle instability (CAI) has shown to affect activities related to the distal leg muscles while walking. Its effects on proximal muscle activities of the leg, both for the injured- (IN) and uninjured-side (NON), remain unclear. Therefore, the aim was to compare the difference of the motor control strategy in ipsilateral and contralateral proximal joints while unperturbed walking and perturbed walking between individuals with CAI and matched controls.
Materials and methods
In a cross-sectional study, 13 participants with unilateral CAI and 13 controls (CON) walked on a split-belt treadmill with and without random left- and right-sided perturbations. EMG amplitudes of muscles at lower extremities were analyzed 200 ms after perturbations, 200 ms before, and 100 ms after (Post100) heel contact while walking. Onset latencies were analyzed at heel contacts and after perturbations. Statistical significance was set at alpha≤0.05 and 95% confidence intervals were applied to determine group differences. Cohen’s d effect sizes were calculated to evaluate the extent of differences.
Results
Participants with CAI showed increased EMG amplitudes for NON-rectus abdominus at Post100 and shorter latencies for IN-gluteus maximus after heel contact compared to CON (p<0.05). Overall, leg muscles (rectus femoris, biceps femoris, and gluteus medius) activated earlier and less bilaterally (d = 0.30–0.88) and trunk muscles (bilateral rectus abdominus and NON-erector spinae) activated earlier and more for the CAI group than CON group (d = 0.33–1.09).
Conclusion
Unilateral CAI alters the pattern of the motor control strategy around proximal joints bilaterally. Neuromuscular training for the muscles, which alters motor control strategy because of CAI, could be taken into consideration when planning rehabilitation for CAI.
KW - Ankles
KW - Walking
KW - Electromyography
KW - Hip
KW - Skeletal joints
KW - Knees
KW - Legs
KW - Musculoskeletal injury
Y1 - 2020
U6 - https://doi.org/10.1371/journal.pone.0247581
SN - 1932-6203
VL - 16
IS - 2
PB - PLOS
CY - San Francisco
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 - GEN
A1 - Risch, Lucie
A1 - Stoll, Josefine
A1 - Schomöller, Anne
A1 - Engel, Tilman
A1 - Mayer, Frank
A1 - Cassel, Michael
T1 - Intraindividual Doppler Flow Response to Exercise Differs Between Symptomatic and Asymptomatic Achilles Tendons
T2 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - Objective: This study investigated intraindividual differences of intratendinous blood flow (IBF) in response to running exercise in participants with Achilles tendinopathy.
Design: This is a cross-sectional study.
Setting: The study was conducted at the University Outpatient Clinic.
Participants: Sonographic detectable intratendinous blood flow was examined in symptomatic and contralateral asymptomatic Achilles tendons of 19 participants (42 ± 13 years, 178 ± 10 cm, 76 ± 12 kg, VISA-A 75 ± 16) with clinically diagnosed unilateral Achilles tendinopathy and sonographic evident tendinosis.
Intervention: IBF was assessed using Doppler ultrasound “Advanced Dynamic Flow” before (Upre) and 5, 30, 60, and 120 min (U5–U120) after a standardized submaximal constant load run.
Main Outcome Measure: IBF was quantified by counting the number (n) of vessels in each tendon.
Results: At Upre, IBF was higher in symptomatic compared with asymptomatic tendons [mean 6.3 (95% CI: 2.8–9.9) and 1.7 (0.4–2.9), p < 0.01]. Overall, 63% of symptomatic and 47% of asymptomatic Achilles tendons responded to exercise, whereas 16 and 11% showed persisting IBF and 21 and 42% remained avascular throughout the investigation. At U5, IBF increased in both symptomatic and asymptomatic tendons [difference to baseline: 2.4 (0.3–4.5) and 0.9 (0.5–1.4), p = 0.05]. At U30 to U120, IBF was still increased in symptomatic but not in asymptomatic tendons [mean difference to baseline: 1.9 (0.8–2.9) and 0.1 (-0.9 to 1.2), p < 0.01].
Conclusion: Irrespective of pathology, 47–63% of Achilles tendons responded to exercise with an immediate acute physiological IBF increase by an average of one to two vessels (“responders”). A higher amount of baseline IBF (approximately five vessels) and a prolonged exercise-induced IBF response found in symptomatic ATs indicate a pain-associated altered intratendinous “neovascularization.”
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 746
KW - achilles tendinopathy
KW - tendinosis
KW - neovascularization
KW - ultrasound
KW - advanced dynamic flow
KW - sonography
Y1 - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-542865
SN - 1866-8364
SP - 1
EP - 8
PB - Universitätsverlag Potsdam
CY - Potsdam
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 - 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 - 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 - Henschke, Jakob
A1 - Zecher, Mahli Megan
A1 - Mayer, Frank
A1 - Engel, Tilman
T1 - Contralateral repeated bout effect following preconditioning exercises
BT - a systematic review
JF - Sport sciences for health
N2 - Background Recent studies indicate the existence of a repeated bout effect on the contralateral untrained limb following eccentric and isometric contractions. Aims This review aims to summarize the evidence for magnitude, duration and differences of this effect following isometric and eccentric preconditioning exercises. Methods Medline, Cochrane, and Web of science were searched from January 1971 until September 2020. Randomized controlled trials, case-control studies and cross-sectional studies were identified by combining keywords and synonyms (e.g., "contralateral", "exercise", "preconditioning", "protective effect"). At least two of the following outcome parameters were mandatory for study inclusion: strength, muscle soreness, muscle swelling, limb circumference, inflammatory blood markers or protective index (relative change of aforementioned measures). Results After identifying 1979 articles, 13 studies were included. Most investigations examined elbow flexors and utilized eccentric isokinetic protocols to induce the contralateral repeated bout effect. The magnitude of protection was observed in four studies, smaller values of the contralateral when compared to the ipsilateral repeated bout effect were noted in three studies. The potential mechanism is thought to be of neural central nature since no differences in peripheral muscle activity were observed. Time course was examined in three investigations. One study showed a smaller protective effect following isometric preconditioning when compared to eccentric preconditioning exercises. Conclusions The contralateral repeated bout effect demonstrates a smaller magnitude and lasts shorter than the ipsilateral repeated bout effect. Future research should incorporate long-term controlled trials including larger populations to identify central mechanisms. This knowledge should be used in clinical practice to prepare immobilized limbs prospectively for an incremental load.
KW - musculoskeletal physiological phenomena
KW - muscle damage
KW - adaptation
KW - Crossover
KW - muscle soreness
KW - isometric contraction
Y1 - 2021
U6 - https://doi.org/10.1007/s11332-021-00804-0
SN - 1824-7490
SN - 1825-1234
VL - 18
IS - 1
SP - 1
EP - 10
PB - Soringer Italia
CY - Milan
ER -