Refine
Year of publication
Document Type
- Article (30)
- Postprint (10)
- Conference Proceeding (8)
- Other (5)
- Doctoral Thesis (1)
- Working Paper (1)
Language
- English (55)
Is part of the Bibliography
- yes (55)
Keywords
- EMG (8)
- sonography (5)
- achilles tendinopathy (4)
- kinematics (4)
- Achilles and patellar tendon (3)
- Stumbling (3)
- advanced dynamic flow (3)
- electromyography (3)
- low back pain (3)
- non-athletes (3)
- perturbation (3)
- stumbling (3)
- training adaptation (3)
- ultrasound (3)
- young athletes (3)
- Ankles (2)
- Core (2)
- Electromyography (2)
- Gait perturbation (2)
- Hip (2)
- Knees (2)
- Legs (2)
- MiSpEx* (2)
- Musculoskeletal injury (2)
- Perturbation (2)
- Skeletal joints (2)
- Split-belt treadmill (2)
- Walking (2)
- athletes (2)
- biomechanics (2)
- diagnostic techniques and procedures (2)
- eccentric (2)
- echo intensity (2)
- exercise (2)
- exercise induced muscle damage (2)
- gait (2)
- inflammation (2)
- instability (2)
- interleukin-6 (2)
- internleukin-10 (2)
- isokinetics (2)
- kinetics (2)
- muscle fatigue (2)
- muscle quality (2)
- muscle strength (2)
- neovascularization (2)
- neuromuscular (2)
- overhead athlete (2)
- phase angle (2)
- reliability (2)
- repeated bout effect (2)
- rotator cuff (2)
- runners (2)
- shoulder joint (2)
- tendinosis (2)
- trunk muscles (2)
- tumor necrosis factor-α (2)
- unstable resistance training (2)
- validation study (2)
- wearable devices (2)
- Ankle (1)
- Crossover (1)
- EMC (1)
- Gait (1)
- Gang (1)
- Inertial measurement units (1)
- Isokinetics (1)
- Lifting (1)
- Lower extremity (1)
- Lower-extremity perturbations (1)
- MISPEX (1)
- MiSpEx (1)
- Motion analysis (1)
- Perturbationen (1)
- Reflexaktivität (1)
- Reliability (1)
- Rumpf (1)
- Running (1)
- Rückenschmerz (1)
- Scapular dyskinesis (1)
- Scapulohumeral rhythm (1)
- Scapulothoracic (1)
- Stolpern (1)
- Treadmill (1)
- Treadmill walking (1)
- Trunk (1)
- Trunk kinematics (1)
- adaptation (1)
- avoid magnetometers (1)
- back motion assessment (1)
- balance (1)
- body composition (1)
- combined training (1)
- concentric training (1)
- conomics (1)
- core (1)
- curve analysis (1)
- drift correction (1)
- eccentric training (1)
- elite athletes (1)
- exercise treatments (1)
- feedback (1)
- feedforward (1)
- human motion analysis (1)
- intratendinous blood flow (1)
- isokinetic testing (1)
- isometric contraction (1)
- joint angle (1)
- joint angle estimation (1)
- kinematic parameters (1)
- kinetic parameters (1)
- lumbopelvic (1)
- mid-portion achilles tendinopathy (1)
- muscle damage (1)
- muscle soreness (1)
- musculoskeletal (1)
- musculoskeletal physiological phenomena (1)
- open science (1)
- pipe (1)
- political science (1)
- prevention (1)
- reflex (1)
- reflexes (1)
- replication (1)
- reproduction (1)
- research transparency (1)
- running (1)
- scapular muscle activity (1)
- sensorimotor parameters (1)
- shoulder (1)
- skinfold thickness (1)
- split-belt treadmill (1)
- subcutaneous adipose tissue (1)
- training intervention (1)
- trunk (1)
- trunk and hip coordination (1)
- ultrasonography (1)
- validation against optical motion capture (1)
- water (1)
- water pipe (1)
Institute
- Department Sport- und Gesundheitswissenschaften (42)
- Strukturbereich Kognitionswissenschaften (6)
- Extern (3)
- Hochschulambulanz (3)
- Humanwissenschaftliche Fakultät (2)
- Department Psychologie (1)
- Fachgruppe Volkswirtschaftslehre (1)
- Fakultät für Gesundheitswissenschaften (1)
- Gesundheitsmanagement (1)
- Institut für Ernährungswissenschaft (1)
Acute ankle sprain leads in 40% of all cases to chronic ankle instability (CAI). CAI is related to a variety of motor adaptations at the lower extremities. Previous investigations identified increased muscle activities while landing in CAI compared to healthy control participants. However, it remains unclear whether muscular alterations at the knee muscles are limited to the involved (unstable) ankle or are also present at the uninvolved leg. The latter might potentially indicate a risk of ankle sprain or future injury on the uninvolved leg. Purpose: To assess if there is a difference of knee muscle activities between the involved and uninvolved leg in participants with CAI during perturbed walking. Method: 10 participants (6 females; 4 males; 26±4 years; 169±9 cm; 65±7 kg) with unilateral CAI walked on a split-belt treadmill (1m/s) for 5 minutes of baseline walking and 6 minutes of perturbed walking (left and right side, each 10 perturbations). Electromyography (EMG) measurements were performed at biceps femoris (BF) and rectus femoris (RF). EMG amplitude (RMS; normalized to MVIC) were analyzed for 200ms pre-heel contact (Pre200), 100ms post heel contact (Post100) and 200ms after perturbation (Pert200). Data was analyzed by paired t-test/Wilcoxon test based on presence or absence of normal distribution (Bonferroni adjusted α level p≤ 0.0125). Results: No statistical difference was found between involved and uninvolved leg for RF (Pre200: 4±2% and 11± 22%, respectively, p= 0.878; Post100: 10± 5 and 18±31%, p=0.959; Pert200: 6±3% and 13±24%, p=0.721) as well as for BF (Pre200: 12±7% and 11±6, p=0.576; Post100: 10±7% and 9±7%, p=0.732; Pert200: 7±4 and 7±7%, p=0.386). Discussion: No side differences in muscle activity could be revealed for assessed feedforward and feedback responses (perturbed and unperturbed) in unilateral CAI. Reduced inter-individual variability of muscular activities at the involved leg might indicate a rather stereotypical response pattern. It remains to be investigated, whether muscular control at the knee is not affected by CAI, or whether both sides adapted in a similar style to the chronic condition at the ankle.
Background
Back pain patients (BPP) show delayed muscle onset, increased co-contractions, and variability as response to quasi-static sudden trunk loading in comparison to healthy controls (H). However, it is unclear whether these results can validly be transferred to suddenly applied walking perturbations, an automated but more functional and complex movement pattern. There is an evident need to develop research-based strategies for the rehabilitation of back pain. Therefore, the investigation of differences in trunk stability between H and BPP in functional movements is of primary interest in order to define suitable intervention regimes. The purpose of this study was to analyse neuromuscular reflex activity as well as three-dimensional trunk kinematics between H and BPP during walking perturbations.
Methods
Eighty H (31m/49f;29±9yrs;174±10cm;71±13kg) and 14 BPP (6m/8f;30±8yrs;171±10cm;67±14kg) walked (1m/s) on a split-belt treadmill while 15 right-sided perturbations (belt decelerating, 40m/s2, 50ms duration; 200ms after heel contact) were randomly applied. Trunk muscle activity was assessed using a 12-lead EMG set-up. Trunk kinematics were measured using a 3-segment-model consisting of 12 markers (upper thoracic (UTA), lower thoracic (LTA), lumbar area (LA)). EMG-RMS ([%],0-200ms after perturbation) was calculated and normalized to the RMS of unperturbed gait. Latency (TON;ms) and time to maximum activity (TMAX;ms) were analysed. Total motion amplitude (ROM;[°]) and mean angle (Amean;[°]) for extension-flexion, lateral flexion and rotation were calculated (whole stride cycle; 0-200ms after perturbation) for each of the three segments during unperturbed and perturbed gait. For ROM only, perturbed was normalized to unperturbed step [%] for the whole stride as well as the 200ms after perturbation. Data were analysed descriptively followed by a student´s t-test to account for group differences. Co-contraction was analyzed between ventral and dorsal muscles (V:R) as well as side right:side left ratio (Sright:Sleft). The coefficient of variation (CV;%) was calculated (EMG-RMS;ROM) to evaluate variability between the 15 perturbations for all groups. With respect to unequal distribution of participants to groups, an additional matched-group analysis was conducted. Fourteen healthy controls out of group H were sex-, age- and anthropometrically matched (group Hmatched) to the BPP.
Results
No group differences were observed for EMG-RMS or CV analysis (EMG/ROM) (p>0.025). Co-contraction analysis revealed no differences for V:R and Srigth:Sleft between the groups (p>0.025). BPP showed an increased TON and TMAX, being significant for Mm. rectus abdominus (p = 0.019) and erector spinae T9/L3 (p = 0.005/p = 0.015). ROM analysis over the unperturbed stride cycle revealed no differences between groups (p>0.025). Normalization of perturbed to unperturbed step lead to significant differences for the lumbar segment (LA) in lateral flexion with BPP showing higher normalized ROM compared to Hmatched (p = 0.02). BPP showed a significant higher flexed posture (UTA (p = 0.02); LTA (p = 0.004)) during normal walking (Amean). Trunk posture (Amean) during perturbation showed higher trunk extension values in LTA segments for H/Hmatched compared to BPP (p = 0.003). Matched group (BPP vs. Hmatched) analysis did not show any systematic changes of all results between groups.
Conclusion
BPP present impaired muscle response times and trunk posture, especially in the sagittal and transversal planes, compared to H. This could indicate reduced trunk stability and higher loading during gait perturbations.
Background
Back pain patients (BPP) show delayed muscle onset, increased co-contractions, and variability as response to quasi-static sudden trunk loading in comparison to healthy controls (H). However, it is unclear whether these results can validly be transferred to suddenly applied walking perturbations, an automated but more functional and complex movement pattern. There is an evident need to develop research-based strategies for the rehabilitation of back pain. Therefore, the investigation of differences in trunk stability between H and BPP in functional movements is of primary interest in order to define suitable intervention regimes. The purpose of this study was to analyse neuromuscular reflex activity as well as three-dimensional trunk kinematics between H and BPP during walking perturbations.
Methods
Eighty H (31m/49f;29±9yrs;174±10cm;71±13kg) and 14 BPP (6m/8f;30±8yrs;171±10cm;67±14kg) walked (1m/s) on a split-belt treadmill while 15 right-sided perturbations (belt decelerating, 40m/s2, 50ms duration; 200ms after heel contact) were randomly applied. Trunk muscle activity was assessed using a 12-lead EMG set-up. Trunk kinematics were measured using a 3-segment-model consisting of 12 markers (upper thoracic (UTA), lower thoracic (LTA), lumbar area (LA)). EMG-RMS ([%],0-200ms after perturbation) was calculated and normalized to the RMS of unperturbed gait. Latency (TON;ms) and time to maximum activity (TMAX;ms) were analysed. Total motion amplitude (ROM;[°]) and mean angle (Amean;[°]) for extension-flexion, lateral flexion and rotation were calculated (whole stride cycle; 0-200ms after perturbation) for each of the three segments during unperturbed and perturbed gait. For ROM only, perturbed was normalized to unperturbed step [%] for the whole stride as well as the 200ms after perturbation. Data were analysed descriptively followed by a student´s t-test to account for group differences. Co-contraction was analyzed between ventral and dorsal muscles (V:R) as well as side right:side left ratio (Sright:Sleft). The coefficient of variation (CV;%) was calculated (EMG-RMS;ROM) to evaluate variability between the 15 perturbations for all groups. With respect to unequal distribution of participants to groups, an additional matched-group analysis was conducted. Fourteen healthy controls out of group H were sex-, age- and anthropometrically matched (group Hmatched) to the BPP.
Results
No group differences were observed for EMG-RMS or CV analysis (EMG/ROM) (p>0.025). Co-contraction analysis revealed no differences for V:R and Srigth:Sleft between the groups (p>0.025). BPP showed an increased TON and TMAX, being significant for Mm. rectus abdominus (p = 0.019) and erector spinae T9/L3 (p = 0.005/p = 0.015). ROM analysis over the unperturbed stride cycle revealed no differences between groups (p>0.025). Normalization of perturbed to unperturbed step lead to significant differences for the lumbar segment (LA) in lateral flexion with BPP showing higher normalized ROM compared to Hmatched (p = 0.02). BPP showed a significant higher flexed posture (UTA (p = 0.02); LTA (p = 0.004)) during normal walking (Amean). Trunk posture (Amean) during perturbation showed higher trunk extension values in LTA segments for H/Hmatched compared to BPP (p = 0.003). Matched group (BPP vs. Hmatched) analysis did not show any systematic changes of all results between groups.
Conclusion
BPP present impaired muscle response times and trunk posture, especially in the sagittal and transversal planes, compared to H. This could indicate reduced trunk stability and higher loading during gait perturbations.
Stumbling led to an increase in ROM, compared to unperturbed gait, in all segments and planes. These increases ranged between 107 +/- 26% (UTA/rotation) and 262 +/- 132% (UTS/lateral flexion), significant only in lateral flexion. EMG activity of the trunk was increased during stumbling (abdominal: 665 +/- 283%; back: 501 +/- 215%), without significant differences between muscles. Provoked stumbling leads to a measurable effect on the trunk, quantifiable by an increase in ROM and EMG activity, compared to normal walking. Greater abdominal muscle activity and ROM of lateral flexion may indicate a specific compensation pattern occurring during stumbling. (C) 2015 Elsevier Ltd. All rights reserved.
The aim of this study was to investigate the effect of a 6-week sensorimotor or resistance training on maximum trunk strength and response to sudden, high-intensity loading in athletes. Interventions showed no significant difference for maximum strength in concentric and eccentric testing (p>0.05). For perturbation compensation, higher peak torque response following SMT (Extension: +24Nm 95%CI +/- 19Nm; Rotation: + 19Nm 95%CI +/- 13Nm) and RT (Extension: +35Nm 95%CI +/- 16Nm; Rotation: +5Nm 95%CI +/- 4Nm) compared to CG (Extension: -4Nm 95%CI +/- 16Nm; Rotation: -2Nm 95%CI +/- 4Nm) was present (p<0.05).