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Fig. 2. (a) Gait width and (b) gait speed at 3 measurements (T0, T1, T2) for preferred and maximal gait speed (gait condition). *Indicates significant
post-hoc effects of time for gait width. #Indicates significant post-hoc effects of time on preferred gait speed.
There was also a significant time effect on gait speed
(F(2,42) = 5.458, p = 0.008) as well as a significant
time × gait condition interaction (F(2,42) = 5.399,
p = 0.008). Compared with baseline, the preferred gait
speed had increased by 8.3% at T1 (p = 0.001) and by
11.5% at T2 (p < 0.001). In contrast, no significant
changes from baseline were observed in the maximal
gait speed (Fig. 2b).
Instrumented balance assessments
Changes in leg angles across time could only be statisti-
cally tested if side steps were made at all measurements
(T0–T2). As some participants failed to make any side
steps (i.e. only made cross steps) or grabbed the rai-
ling system before stepping, a total of 19 participants
could be included in the analysis of trials with known
perturbation direction and 13 in the analysis of trials
with unknown directions. The mean limit of stability
was 2.135 m/s 2 (range 0.375–4.375 m/s 2 ).
For the known direction perturbations, the leg
angle showed a main effect of time (F(2,36) = 12.053,
p < 0.001). There was an increase of 5.9% in leg angle
from baseline to T1 (p = 0.003), which persisted at T2
(8.0%; p = 0.001). In contrast, leg angle for the unk-
nown direction perturbations did not show a significant
effect of time (F(2,24) = 0.107, p = 0.899) (see Fig. 3a).
For the known direction perturbations, there was a
significant effect of time on success rate (χ 2 (2) = 12.559,
p = 0.002). Compared with the 70% success rate at ba-
seline, participants were more successful at T1 (90%;
p = 0.007), which result tended to persist at T2 (90%;
p = 0.075). For the unknown direction perturbations,
no significant effects of time were found (χ 2 (2) = 4.388,
p = 0.111) (see Fig. 3b).
Physical tests
Hip adductor muscle tone showed a significant time
effect (χ 2 (2) = 33.890, p < 0.001). The MAS scores
decreased from baseline to T1 (p < 0.001), and subse-
quently increased from T1 to T2 (p = 0.001), although
they did not reach the baseline values (T0 vs T2,
p = 0.001). Hip adductor muscle strength also showed a
Fig. 3. (a) Leg angle and (b) success rate at 3 measurements (T0, T1, T2) for known and unknown perturbation directions. #Indicates significant
post-hoc effects of time in known perturbation directions. *Indicates significant effect of time.
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