Table 1.
Mean ± SD and median (range) of muscle onset times, normalized muscle amplitudes, kinematic amplitudes and time of peak kinematics.
| Sled | Startle | |
| EMG onset time (ms) | ||
| C4 level | 129 ± 60 | 123 ± 64 |
| 140 (34 – 191) | 105 (58 – 222) | |
| C6 level | 232 ± 175 | 182 ± 120 |
| 194 (66 – 571) | 126 (60 – 417) | |
| EMG amplitude (%MVC) | ||
| C4 level | 137 ± 168 a | 136 ± 123 a |
| 107 (12 – 532) | 80 (39 – 337) | |
| C6 level | 40 ± 25 | 57 ± 53 a |
| 36 (9 – 77) | 28 (15 – 150) | |
| Kinematics | ||
| Head accel (m/s2) | 9.7 ± 3.3 | 1.9 ± 1.0 |
| 10.1 (5.6 – 15.2) | 1.6 (0.5 – 3.5) | |
| Head extension (°) | 15.6 ± 5.6 | 1.9 ± 3.1 a |
| 12.6 (10.0 – 25.9) | 0.5 (0.1 – 8.8) | |
| Retraction (mm) | 18.4 ± 6.9 | 4.3 ± 2.4 a |
| 19.4 (8.7 – 31.3) | 5.2 (1.0 – 6.6) | |
| Time to peak kinematics (ms) | ||
| Head accel | 123 ± 11 | 272 ± 168 a |
| 122 (106 – 145) | 215 (124 – 581) | |
| Head extension | 208 ± 51 a | 557 ± 200 |
| 190 (170 – 330) | 510 (290 – 770) | |
| Retraction | 173 ± 48 | 373 ± 187 |
| 160 (110 – 240) | 330 (130 – 710) | |
a non-normally distributed, Shapiro-Wilks p < 0.05