TY  - CHAP
A1  - Engel, Tilman
A1  - Müller, Juliane
A1  - Müller, Steffen
A1  - Reschke, Antje
A1  - Kopinski, Stephan
A1  - Mayer, Frank
T1  - Validity and reliability of a new customised split-belt treadmill provoking unexpected walking perturbations
T2  - Medicine and science in sports and exercise : official journal of the American College of Sports Medicine
Y1  - 2013
SN  - 0195-9131
SN  - 1530-0315
VL  - 45
IS  - 5
SP  - 462
EP  - 462
PB  - Lippincott Williams & Wilkins
CY  - Philadelphia
ER  - 
TY  - JOUR
A1  - Engel, Tilman
A1  - Mueller, Juliane
A1  - Kopinski, Stephan
A1  - Reschke, Antje
A1  - Mueller, Steffen
A1  - Mayer, Frank
T1  - Unexpected walking perturbations: Reliability and validity of a new treadmill protocol to provoke muscular reflex activities at lower extremities and the trunk
JF  - Journal of biomechanics
N2  - Instrumented treadmills offer the potential to generate standardized walking perturbations, which are particularly rapid and powerful. However, technical requirements to release adequate perturbations regarding timing, duration and amplitude are demanding. This study investigated the test-retest reliability and validity of a new treadmill perturbation protocol releasing rapid and unexpected belt perturbations to provoke muscular reflex responses at lower extremities and the trunk. Fourteen healthy participants underwent two identical treadmill walking protocols, consisting of 10 superimposed one-sided belt perturbations (100 ms duration; 2 m/s amplitude), triggered by a plantar pressure insole 200 ms after heel contact. Delay, duration and amplitude of applied perturbations were recorded by 3D-motion capture. Muscular reflex responses (within 200 ms) were measured at lower extremities and the trunk (10-lead EMG). Data was analyzed descriptively (mean +/- SD). Reliability was analyzed using test-retest variability (TRV%) and limits of agreement (LoA, bias +/- 1.96*SD). Perturbation delay was 202 14 ms, duration was 102 +/- 4 ms and amplitude was 2.1 +/- 0.01 m/s. TRV for perturbation delay, duration and amplitude ranged from 5.0% to 5.7%. LoA reached 3 +/- 36 ms for delay, 2 +/- 13 ms for duration and 0.0 +/- 0.3 m/s for amplitude. EMG amplitudes following perturbations ranged between 106 +/- 97% and 909 +/- 979% of unperturbed gait and EMG latencies between 82 +/- 14 ms and 106 +/- 16 ms. Minor differences between preset and observed perturbation characteristics and results of test-retest analysis prove a high validity with excellent reliability of the setup. Therefore, the protocol tested can be recommended to provoke muscular reflex responses at lower extremities and the trunk in perturbed walking. (C) 2017 Elsevier Ltd. All rights reserved.
KW  - Perturbation
KW  - Stumbling
KW  - Gait
KW  - Treadmill
KW  - Reliability
KW  - MiSpEx
Y1  - 2017
U6  - https://doi.org/10.1016/j.jbiomech.2017.02.026
SN  - 0021-9290
SN  - 1873-2380
VL  - 55
SP  - 152
EP  - 155
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - CHAP
A1  - Reschke, Antje
A1  - Müller, Juliane
A1  - Müller, Steffen
A1  - Engel, Tilman
A1  - Mayer, Frank
T1  - Three-dimensional spine kinematics during perturbed treadmill walking - a pilot study
T2  - Medicine and science in sports and exercise : official journal of the American College of Sports Medicine
Y1  - 2013
SN  - 0195-9131
SN  - 1530-0315
VL  - 45
IS  - 5
SP  - 172
EP  - 172
PB  - Lippincott Williams & Wilkins
CY  - Philadelphia
ER  - 
TY  - JOUR
A1  - Müller, Juliane
A1  - Müller, Steffen
A1  - Engel, Tilman
A1  - Reschke, Antje
A1  - Baur, Heiner
A1  - Mayer, Frank
T1  - Stumbling reactions during perturbed walking: Neuromuscular reflex activity and 3-D kinematics of the trunk - A pilot study
JF  - Journal of biomechanics
N2  - 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.
KW  - Trunk kinematics
KW  - Treadmill walking
KW  - Gait perturbation
KW  - EMG
Y1  - 2016
U6  - https://doi.org/10.1016/j.jbiomech.2015.09.041
SN  - 0021-9290
SN  - 1873-2380
VL  - 49
SP  - 933
EP  - 938
PB  - Elsevier
CY  - Oxford
ER  -