Baseline gait and physical activity features
| Feature | Mean±SD | Median (IQR) |
| GRF impulses (N×s): | ||
| Vertical GRF impulse | 454.5±113.7 | 439.5 (370.5 to 523.5) |
| Medial GRF impulse | 18.9±8.1 | 17.6 (13.0 to 23.1) |
| Lateral GRF impulse | 1.6±1.0 | 1.5 (0.9 to 2.1) |
| Anterior GRF impulse | 23.9±7.0 | 23.1 (18.5 to 28.3) |
| GRF local maxima (N): | ||
| Vertical GRF first peak | 850.6±179.5 | 826.9 (718.2 to 962.9) |
| Posterior GRF peak | 134.1±41.1 | 128.5 (103.5 to 156.4) |
| Early medial GRF peak | 47.6±15.8 | 45.7 (36.3 to 57.5) |
| GRF loading and unloading rates (N/s): | ||
| Maximum instantaneous vertical GRF loading rate | 11555±4077 | 10981 (8776 to 13379) |
| Maximum instantaneous vertical GRF unloading rate | 10204±2289 | 9983 (8564 to 11536) |
| Timing of GRF local maxima/minima (% stance): | ||
| Vertical GRF first peak | 25.9±3.5 | 25.7 (23.8 to 28.0) |
| Vertical GRF second peak | 75.5±2.5 | 75.9 (74.5 to 77.0) |
| Vertical GRF valley (midstance minimum) | 48.3±3.5 | 48.3 (46.0 to 50.8) |
| Posterior GRF peak | 17.5±2.4 | 17.5 (16.1 to 18.9) |
| Anterior GRF peak | 85.4±1.4 | 85.5 (84.6 to 86.4) |
| Early lateral GRF peak | 7.1±1.7 | 7.2 (6.1 to 8.2) |
| Early medial GRF peak | 26.3±5.7 | 26.0 (22.2 to 30.1) |
| Late medial GRF peak | 72.3±5.7 | 73.5 (70.0 to 76.3) |
| Spatiotemporal parameters: | ||
| Gait speed (m/s) | 1.35±0.20 | 1.34 (1.21 to 1.48) |
| Stance time (s) | 0.7±0.1 | 0.7 (0.7 to 0.8) |
| Angle formed by centre of pressure path and direction of travel, ‘toe-out angle’ (degrees, negative values indicate varus) | −3.7±5.3 | −3.5 (−7.2 to −0.2) |
| Accelerometer derived physical activity measures: | ||
| Step count | 9554±3919 | 9149 (6812 to 11533) |
| Time spent lying (% total wear time) | 9.2±10.4 | 5.6 (2.0 to 12.5) |
| Mean signal vector magnitude (milligravity) | 4.0±1.4 | 3.8 (3.1 to 4.7) |
GRF, ground reaction force.