1 Introduction
1D | First (dominant) post-perturbation step |
2ND | Second (non-dominant) post-perturbation step |
3D | Third (dominant) post-perturbation step |
4ND | Fourth (non-dominant) post-perturbation step |
5D | Fifth (dominant) post-perturbation step |
6ND | Sixth (non-dominant) post-perturbation step |
6S | Total perturbation response |
ANOVA | Analysis of variances |
AP | Anterior-posterior |
BoS | Base of support |
CoM | Centre of mass |
D | Dominant |
ML | Medio-lateral |
MoS | Margins of stability |
ND | Non-dominant |
NPD | Non-dominant pre-perturbation step |
PD | Dominant pre-perturbation step |
VT | Vertical |
XCoM | Extrapolated centre of mass |
2 Methods
2.1 Participants
2.2 Equipment
2.3 Protocol
2.4 Data analyses
2.4.1 Outcome measures
2.5 Statistical analyses
3 Results
3.1 Baseline walking
Parameter | Young adults | Older adults | Main effect (sides) | Between subjects effect (Group) | Interaction effect (Steps × Group) | ||||
---|---|---|---|---|---|---|---|---|---|
Mean ± SD | Mean ± SD |
F
|
p
|
F
|
p
|
F
|
p
| ||
ML MoS [m] | D | 0.065 ± 0.012 | 0.061 ± 0.013 |
31.339
|
< 0.001
| 1.218 | 0.286 | 0.388 | 0.542 |
ND |
0.053 ± 0.006
|
0.047 ± 0.013
| |||||||
AP MoS [m] | D | 0.169 ± 0.047 | 0.142 ± 0.052 | 2.888 | 0.109 | 1.729 | 0.207 | 1.009 | 0.330 |
ND | 0.175 ± 0.044 | 0.143 ± 0.045 | |||||||
Step time [s] | D | 0.544 ± 0.046 | 0.555 ± 0.033 | 0.015 | 0.905 | 0.285 | 0.600 | 0.113 | 0.741 |
ND | 0.545 ± 0.043 | 0.554 ± 0.032 | |||||||
Step length [m] | D | 0.680 ± 0.066 | 0.656 ± 0.125 | 2.488 | 0.134 | 0.430 | 0.521 | 2.113 | 0.165 |
ND | 0.692 ± 0.066 | 0.656 ± 0.113 | |||||||
Step width [m] | D | 0.126 ± 0.032 | 0.113 ± 0.056 | 1.539 | 0.233 | 0.356 | 0.559 | 0.293 | 0.596 |
ND | 0.126 ± 0.032 | 0.113 ± 0.056 | |||||||
LDSML | – | 1.829 ± 0.294 | 1.798 ± 0.334 | – | – | – | – | – | – |
LDSAP | – | 1.585 ± 0.263 | 1.404 ± 0.262 | – | – | – | – | – | – |
LDSVT | – | 1.826 ± 0.428 | 1.701 ± 0.366 | – | – | – | – | – | – |