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. 2017 Dec 27;12(12):e0190135. doi: 10.1371/journal.pone.0190135

Table 1. Means and standard deviations of kinematic parameters.

Step Posture p-value/F-value
ES
RE TF1 TF2 Posture Step Posture × Step
TrunkTD (deg) L 6.2±3.4 30.4±6.2 47.3±6.9
U-1 6.1±3.3 29.8±6.3 46.6±5.2
U0 5.2±5.6 26.2±6.5 43.8±5.9
U+1 12.6±4.4 32.6±6.7 48.9±3.9
TrunkTO (deg) L 5.0±3.4 29.7±5.1 45.9±7.6
U-1 5.2±5.4 23.9±10.1 43.1±3.9
U0 11.5±5.0 24.2±13.1 49.1±6.2
U+1 7.5±5.4 27.0±11.3 46.2±4.0
Normalized CoMTD L 1.12±0.02 1.10±0.02 1.08±0.02 0.00/120 0.00/144 0.00/5.96
U-1 1.12±0.02 1.07±0.08 1.07±0.02
U0 1.16±0.03 1.14±0.03 1.11±0.03a 0.95 0.96 0.49
U+1 1.06±0.02 1.05±0.02 1.04±0.03
Normalized CoMTO L 1.12±0.02 1.10±0.02 1.08±0.02 0.00/42.5 0.00/105 0.69/0.64
U-1 1.05±0.03 1.02±0.03 1.01±0.03
U0 1.17±0.02 1.15±0.03 1.13±0.03 0.87 0.94 0.09
U+1 1.11±0.04 1.11±0.06 1.08±0.06
Normalized ELTD L 1.14±0.03 1.16±0.03 1.16±0.03 0.01/6.24 0.00/15.1 0.04/3.97
U-1 1.14±0.04 1.15±0.04 1.15±0.03
U0 1.14±0.02 1.14±0.03 1.13±0.03 0.51 0.71 0.39
U+1 1.08±0.02 1.10±0.03 1.10±0.02
Normalized ELTO L 1.12±0.03 1.10±0.02 1.09±0.03 0.00/7.16 0.00/37.3 0.00/5.69
U-1 1.07±0.02 1.04±0.01a 1.01±0.02a,b
U0 1.15±0.03 1.15±0.03 1.14±0.03 0.54 0.86 0.48
U+1 1.10±0.03 1.09±0.04 1.07±0.05
HipTD (deg) L 19.9±3.4 43.3±4.0a 53.5±8.2a,b 0.00/458 0.00/19.5 0.00/28.6
U-1 20.4±3.9 37.4±8.7a 53.5±8.2a,b
U0 15.9±3.4 39.1±8.3a 51.0±6.9a,b 0.99 0.83 0.87
U+1 37.7±4.9 42.7±4.4 53.4±7.2a
HipTO (deg) L -12.4±5.0 11.9±7.4a 24.6±9.9a,b 0.00/145 0.33/1.24 0.00/7.89
U-1 -13.0±8.0 11.0±9.2a 24.9±9.6a,b
U0 -8.0±4.1 11.3±8.9a 20.6±8.5a 0.97 0.23 0.66
U+1 -13.1±6.7 11.7±8.4a 22.9±9.2a
KneeTD (deg) L 9.6±4.0 10.8±3.5 10.7±5.3 0.00/9.37 0.00/31.7 0.00/12.9
U-1 9.7±5.3 10.7±5.6 12.2±5.7
U0 14.1±5.6 15.6±6.0 16.3±5.8 0.70 0.88 0.76
U+1 29.2±5.4 22.8±8.4 21.1±8.1
KneeTO (deg) L 40.5±6.3 45.7±6.5 50.4±6.1a 0.00/9.67 0.00/31.1 0.00/5.27
U-1 51.5±10.6 61.4±9.2 70.6±7.0a
U0 30.7±3.6 30.2±4.5 32.9±4.0 0.70 0.88 0.56
U+1 37.2±10.4 43.6±12.6 50.2±7.0a
AnkleTD (deg) L -1.6±2.3 2.1±2.2a 2.7±1.9a 0.15/2.41 0.88/0.21 0.00/3.72
U-1 -1.5±3.0 1.4±2.5 2.6±2.5a
U0 -2.0±10.9 -4.7±15.2 -8.5±17.3 0.37 0.05 0.48
U+1 1.4±3.1 3.3±2.9 3.1±3.3
AnkleTO (deg) L -14.9±6.2 -11.5±2.5 -9.8±4.3 0.29/1.42 0.00/12.3 0.13/1.85
U-1 -2.5±7.2 -2.1±4.4 -2.3±4.6
U0 -18.5±3.0 -16.6±3.2 -13.3±5.5 0.26 0.75 0.31
U+1 -13.7±7.6 -11.8±3.0 -9.5±4.2
αTD (deg) L 66.5±4.6 62.6±5.1 62.2±6.3 0.01/6.52 0.55/0.71 0.37/1.12
U-1 65.0±4.7 63.1±4.4 59.9±7.9
U0 65.6±2.5 63.9±4.4 63.9±3.2 0.52 0.10 0.15
U+1 64.6±2.9 64.0±2.8 63.4±2.7
αTO (deg) L 117±2.7 116±5.9 116±7.3 0.09/2.92 0.00/33.0 0.84/0.44
U-1 119±2.1 120±2.4 120±5.1
U0 120±2.8 119±4.6 120±3.0 0.32 0.84 0.06
U+1 116±2.9 111±3.1 110±2.9

The last three columns show the p-values/F-values and effect size (ES, partial eta squared) of the main effects of posture and step and, the posture×step interaction, respectively. In case of interaction effect, significant differences from RE and TF1 across each step are indicated with ‘a’ and ‘b’, respectively (p<0.05). Accordingly, shaded, bold and underlined values indicate the significant difference from the unperturbed step ‘L’, from the pre-perturbation step ‘U-1’ and from the step-down ‘U0’ (p<0.05), respectively, for each walking posture (N = 12). CoM, center of mass; TD, touchdown; TO, toe-off; ELTD, normalized effective leg length at TD; ELTO, normalized effective leg length at TO; αTD, leg angle at TD; αTO, leg angle at TO; RE, regular erect trunk; TF1, ~30° trunk flexion; TF2, ~50° trunk flexion; U+1, step-up.