Table 1. Sleep architecture at baseline and during sleep restricted and recovery nights.
| Baseline | Restriction 1 | Restriction 2 | Restriction 3 | Restriction 4 | Restriction 5 | Recovery 1 | Recovery 2 | Recovery 3 | P Value | |
| Stage 1(min) | 8.7(6.1-12.0) | 8.0(3.5-10.5) | 3.5(1.5-6.5) | 2.0(1.5-5.0) | 2.5(2.0-7.0) | 3.0(1.5-8.5) | 5.5(1.5-8.5) | 9.5(7.0-14.5) | 5.0(3.2-13.5) | 0.17 |
| Stage 2(min) | 169.7(159.5-215.5) | 94.5*(86.0-112.5) | 85.5*(68.0-111.0) | 100.5*(85.5-115.5) | 93.0*(66.5-114.0) | 114.5*(89.0-124.5) | 165.0(124.5-205.5) | 190.0(173.5-224.5) | 196.0(155.2-211.7) | < 0.001 |
| SWS(min) | 124.0(99.0-152.6) | 121.5(91.5-141.0) | 119.0(87.5-142.0) | 115.0(98.0-126.0) | 117.5(94.0-132.0) | 110.0(95.0-122.0) | 163.0*(124.0-198.5) | 129.5(102.5-160.5) | 137.5(95.0-152.0) | 0.01 |
| REM(min) | 100.0(87.6-109.25) | 43.0*(38.5-52.5) | 51.5*(50.0-70.0) | 62.0*(40.0-71.5) | 53.5*(46.5-70.5) | 67.0*(59.0-72.5) | 102.5(76.5-113.0) | 97.5(87.5-112.0) | 89.0(62.7-116.2) | < 0.001 |
| Stage 1(%) | 2.1(1.4-2.9) | 2.9(1.4-3.8) | 1.3(0.5-2.4) | 0.7(0.5-1.8) | 2.5(0.7-2.4) | 1.0(0.5-2.3) | 1.2(0.4-1.9) | 2.2(1.6-3.1) | 1.4(0.8-3.3) | 0.12 |
| Stage 2(%) | 47.0(38.5-51.2) | 34.7*(34.1-40.5) | 31.9*(24.8-41.8) | 37.1*(33.5-41.5) | 32.8*(23.9-41.9) | 43.0(30.5-45.0) | 36.9(31.5-45.0) | 42.9(38.7-51.5) | 45.3(38.1-52.1) | 0.01 |
| SWS(%) | 27.7(22.9-35.0) | 45.5*(35.2-47.4) | 45.7*(32.1-50.2) | 43.0*(39.5-47.3) | 41.9*(35.4-46.3) | 39.4(35.5-50.8) | 36.3(31.5-44.4) | 29.8(23.3-35.6) | 33.1(22.9-40.7) | 0.03 |
| REM(%) | 24.2(21.4-25.9) | 16.4*(15.2-18.7) | 19.3(17.9-25.2) | 23.0(16.1-25.9) | 19.5(16.7-25.3) | 24.4(20.2-25.7) | 22.6(16.6-29.7) | 22.2(19.7-26.0) | 21.2(14.4-22.4) | 0.02 |
| Sleep efficiency (%) | 88.7(85.3-90.6) | 88.1(84.1-93.8) | 91.3(89.1-93.6) | 93.6*(88.9.-95.6) | 94.3*(93.0-95.6) | 95.9*(93.4-98.0) | 93.4*(92.1-95.0) | 90.8(89.0-94.8) | 88.3(86.5-90.5) | 0.004 |
| Total sleep time(min) | 419.3(396.0-421.2) | 267.0*(252.0-280.0) | 272.0*(260.5-280.0) | 275.0*(273.5-284.0) | 280.0*(252.0-280.0) | 279.5*(271.0-288.0) | 452.0*(444.0-456.2) | 435.5(427.0-454.0) | 418.5(403.0-425.0) | 0.003 |
Values are shown as medians (25%–75% range). Baseline (average of the 3 baseline nights for each volunteer) was used as control and other nights as the comparative groups. Data comparisons with the baseline were performed using a Friedman Repeated Measures Analysis of Variance on Ranks and a Dunn's post-hoc test.
*Significant difference vs. baseline (P<0.05).