Table 1.
Comparison of kinetic and kinematic variables during slow walking, fast walking and running between the AMTI force plate, PedarX and OpenGo.
| Mean ± SD |
Bias (%) |
95% limits of agreement (% grouped mean) |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| AMTI | PedarX | OpenGo | OpenGo vs. AMTI | PedarX vs. AMTI | OpenGo vs. PedarX | OpenGo vs. AMTI | PedarX vs. AMTI | OpenGo vs. PedarX | |
| Slow Walking | |||||||||
| GCT (s) | 0.77 ± 0.06† | 0.78 ± 0.05† | 0.76 ± 0.05† | −0.01 (−1%) | 0.01 (2%) | −0.02 (−3%) | −0.02 (3%) | 0.01 (2%) | 0.03 (4%) |
| Impulse (Ns) | 493 ± 87† | 537 ± 75† | 376 ± 64† | −118 (−24%) | 44 (9%) | −162 (−30%) | 86 (20%) | 81 (16%) | 53 (12%) |
| Fpeak1 (N) | 893 ± 161 | 892 ± 140 | 583 ± 63† | −310 (−35%) | −2 (0%) | −308 (−35%) | 253 (34%) | 151 (17%) | 200 (27%) |
| Fmin (N) | 570 ± 107† | 622 ± 95† | 356 ± 75† | −214 (−38%) | 52 (9%) | −266 (−43%) | 89 (19%) | 89 (15%) | 75 (15%) |
| Fpeak2 (N) | 846 ± 123† | 928 ± 120† | 689 ± 112† | −157 (−19%) | 82 (10%) | −239 (−26%) | 147 (19%) | 167 (19%) | 138 (17%) |
| tFpeak1 (s) | 0.17 ± 0.02† | 0.18 ± 0.03† | 0.20 ± 0.03† | 0.04 (22%) | 0.01 (9%) | 0.02 (12%) | 0.04 (21%) | 0.03 (16%) | 0.04 (20%) |
| tFmin (s) | 0.35 ± 0.04 | 0.35 ± 0.05 | 0.38 ± 0.04 | 0.03 (8%) | 0.00 (0%) | 0.03 (9%) | 0.08 (23%) | 0.03 (9%) | 0.10 (26%) |
| tFpeak2 (s) | 0.61 ± 0.04† | 0.62 ± 0.04† | 0.66 ± 0.05† | 0.05 (8%) | 0.01 (2%) | 0.04 (6%) | 0.04 (6%) | 0.03 (5%) | 0.05 (7%) |
| Fast Walking | |||||||||
| GCT (s) | 0.61 ± 0.05† | 0.62 ± 0.06† | 0.60 ± 0.05‡ | −0.01 (−1%) | 0.02 (3%) | −0.02 (−4%) | −0.02 (3%) | 0.02 (3%) | 0.03 (5%) |
| Impulse (Ns) | 395 ± 79† | 434 ± 73† | 291 ± 57† | −105 (−27%) | 39 (10%) | −144 (−33%) | 83 (24%) | 71 (17%) | 56 (15%) |
| Fpeak1 (N) | 1082 ± 168† | 950 ± 123† | 602 ± 55† | −481 (−44%) | −132 (−12%) | −349 (−37%) | 309 (37%) | 188 (18%) | 219 (28%) |
| Fmin (N) | 425 ± 117† | 483 ± 116† | 276 ± 83† | −148 (−35%) | 59 (14%) | −207 (−43%) | 93 (26%) | 86 (19%) | 105 (28%) |
| Fpeak2 (N) | 856 ± 141† | 944 ± 152† | 673 ± 148† | −183 (−21%) | 88 (10%) | −271 (−29%) | 122 (16%) | 172 (19%) | 131 (16%) |
| tFpeak1 (s) | 0.13 ± 0.02† | 0.14 ± 0.02† | 0.17 ± 0.03† | 0.04 (29%) | 0.01 (7%) | 0.03 (21%) | 0.06 (41%) | 0.02 (13%) | 0.06 (37%) |
| tFmin (s) | 0.31 ± 0.03 | 0.32 ± 0.03 | 0.34 ± 0.04$ | 0.02 (8%) | 0.01 (2%) | 0.02 (6%) | 0.05 (16%) | 0.02 (7%) | 0.06 (18%) |
| tFpeak2 (s) | 0.48 ± 0.05† | 0.49 ± 0.06† | 0.52 ± 0.07† | 0.05 (10%) | 0.02 (3%) | 0.03 (6%) | 0.05 (11%) | 0.01 (3%) | 0.05 (10%) |
| Running | |||||||||
| GCT (s) | 0.34 ± 0.04† | 0.37 ± 0.04† | 0.33 ± 0.04‡ | −0.01 (−2%) | 0.03 (8%) | −0.04 (−10%) | 0.04 (12%) | 0.03 (8%) | 0.04 (12%) |
| Impulse (Ns) | 317 ± 49 | 333 ± 42 | 218 ± 24† | −99 (−31%) | 16 (5%) | −115 (−34%) | 77 (29%) | 55 (17%) | 57 (21%) |
| Fmax (N) | 1701 ± 366 | 1715 ± 294 | 1058 ± 122† | −643 (−38%) | 13 (1%) | −656 (−38%) | 566 (41%) | 257 (15%) | 428 (31%) |
| tFmax (s) | 0.14 ± 0.02 | 0.14 ± 0.02 | 0.19 ± 0.04† | 0.06 (44%) | 0.00 (3%) | 0.05 (39%) | 0.02 (31%) | 0.02 (13%) | 0.05 (29%) |
GCT, ground contact time; Fpeak1, first force peak during ground contact; Fmin, local force minima at approximately 50% of ground contact; Fpeak2, second force peak during ground contact; tFpeak1, time to first force peak; †significantly different to the other two methods; $different to AMTI force plate; ‡ different to PedarX.