Table 3.
Actigraphy outcome of sleep parameters during expedition.
| Variables | Santiago, 520 m | 1st night | 2nd night | 3rd night | 4th night | 5th night | 6th night | 7th night | Santiago, 520 m |
|---|---|---|---|---|---|---|---|---|---|
| Time in bed (min) | |||||||||
| Cycle 1 | 481.4 ± 27.1 | 487.8 ± 65.4 | 511.2 ± 76.6 | 458.4 ± 47.6 | 451.7 ± 73.1 | 443.8 ± 58.3 | – | – | – |
| Cycle 2 | 548.5 ± 99.2§ | 492.5 ± 35.9 | 506.9 ± 47.0 | 442.4 ± 70.7 | 463.2 ± 63.3 | 408.4 ± 44.7*† | 507.0 ± 37.9 | 460.1 ± 57.1 | 534.5 ± 62.2 |
| Total sleep time (min) | |||||||||
| Cycle 1 | 431.3 ± 28.7 | 418.1 ± 48.6 | 428.7 ± 90.5 | 369.7 ± 54.3 | 381.3 ± 72.7 | 379.7 ± 51.4*† | – | – | – |
| TST (% of TIB) | 89.6 ± 3.7 | 86.1 ± 6.8 | 83.8 ± 11.8 | 80.8 ± 10.0 | 84.1 ± 4.7 | 85.9 ± 7.6 | – | – | – |
| Cycle 2 | 477.5 ± 96.9 | 430.9 ± 34.0 | 409.7 ± 44.6 | 368.9 ± 61.5 | 391.1 ± 54.4 | 341.4 ± 32.2*† | 415.9 ± 45.1 | 392.0 ± 60.8 | 439.7 ± 69.1 |
| TST (% of TIB) | 87.0 ± 6.3 | 87.6 ± 5.6 | 81.0 ± 6.7 | 83.6 ± 6.2 | 84.5 ± 4.0 | 83.9 ± 6.2 | 82.3 ± 9.4 | 85.1 ± 6.3 | 82.3 ± 8.7 |
| Latency (min) | |||||||||
| Cycle 1 | 13.7 ± 11.7 | 21.6 ± 20.4 | 33.6 ± 40.1 | 25.6 ± 21.2 | 20.5 ± 19.4 | 21.4 ± 28.8 | – | – | – |
| Cycle 2 | 26.0 ± 24.1 | 20.8 ± 15.7 | 41.6 ± 44.9 | 20.6 ± 21.9 | 21.5 ± 21.8 | 23.1 ± 19.3 | 41.9 ± 36.5 | 11.8 ± 15.1 | 48.4 ± 48.6 |
| Sleep efficiency (%) | |||||||||
| Cycle 1 | 89.6 ± 3.7 | 86.1 ± 6.8 | 83.8 ± 11.8 | 80.9 ± 10.0 | 84.1 ± 4.6 | 85.9 ± 7.6 | – | – | – |
| Cycle 2 | 87.0 ± 6.3 | 87.6 ± 5.6 | 81.0 ± 6.7 | 83.6 ± 6.2 | 84.6 ± 3.9 | 84.0 ± 6.2 | 82.3 ± 9.4 | 85.1 ± 6.2 | 82.3 ± 8.7 |
| Wake after sleep onset (min) | |||||||||
| Cycle 1 | 18.0 ± 7.5 | 34.8 ± 39.8 | 26.7 ± 16.7 | 38.2 ± 43.2 | 23.5 ± 9.4 | 22.9 ± 8.1 | – | – | – |
| Cycle 2 | 34.3 ± 14.3§ | 30.4 ± 15.2 | 32.7 ± 17.4 | 33.6 ± 21.5 | 30.3 ± 15.3 | 31.2 ± 16.5 | 25.1 ± 10.7 | 30.8 ± 12.4 | 31.9 ± 14.7 |
| Awakenings, # | |||||||||
| Cycle 1 | 39.1 ± 17.6 | 46.8 ± 24.5 | 38.4 ± 16.7 | 50.8 ± 34.0 | 39.7 ± 16.2 | 36.2 ± 11.5 | – | – | – |
| Cycle 2 | 35.1 ± 11.2 | 30.2 ± 8.6 | 37.1 ± 14.9 | 33.8 ± 17.4 | 30.2 ± 10.5 | 28.4 ± 13.8 | 26.8 ± 9.8 | 31.7 ± 11.3 | 33.4 ± 12.1 |
Sleep indices from actigraphic measurements. Values are means ± SD. m, meter; min, minute; #: Awakenings. Cycle 1 had 18 subjects and Cycle 2 had 14 subjects with complete actigraphy data due to field constraints and device issues. ∗p < 0.05: Different from respective baseline SL. †p < 0.05: Different from 1st night at high altitude. §p < 0.05: Different from BL of Cycle 1.