@article{ref1,
title="Chronicity of sleep restriction during Army basic military training",
journal="Journal of science and medicine in sport",
year="2022",
author="Larsen, Penelope and Drain, Jace R. and Gibson, Neil and Sampson, John and Michael, Scott and Peoples, Gregory and Groeller, Herbert",
volume="ePub",
number="ePub",
pages="ePub-ePub",
abstract="OBJECTIVES: To investigate: (i) the chronicity and phasic variability of sleep patterns and restriction in recruits during basic military training (BMT); and (ii) identify subjective sleep quality in young adult recruits prior to entry into BMT. <br><br>DESIGN: Prospective observational study. <br><br>METHODS: Sleep was monitored using wrist-worn actigraphy in Army recruits (n = 57, 18-43 y) throughout 12-weeks of BMT. The Pittsburgh Sleep Quality Index (PSQI) was completed in the first week of training to provide a subjective estimate of pre-BMT sleep patterns. A mixed-effects model was used to compare week-to-week and training phase (Orientation, Development, Field, Drill) differences for rates of sub-optimal sleep (6-7 h), sleep restriction (≤6 h), and actigraphy recorded sleep measures. <br><br>RESULTS: Sleep duration was 06:24 ± 00:18h (mean ± SD) during BMT with all recruits experiencing sub-optimal sleep and 42% (n = 24) were sleep restricted for ≥2 consecutive weeks. During Field, sleep duration (06:06 ± 00:36h) and efficiency (71 ± 6%; p < 0.01) were reduced by 15-18 min (minimum - maximum) and 7-8% respectively; whereas, sleep latency (30 ± 15 min), wake after sleep onset (121 ± 23 min), sleep fragmentation index (41 ± 4%) and average awakening length (6.5 ± 1.6 min) were greater than non-Field phases (p < 0.01) by 16-18 min, 28-33 min, 8-10% and 2.5-3 min respectively. Pre-BMT global PSQI score was 5 ± 3, sleep duration and efficiency were 7.4 ± 1.3 h and 88 ± 9% respectively. Sleep schedule was highly variable at pre-BMT (bedtime: 22:34 ± 7:46 h; wake time: 6:59 ± 1:42 h) unlike BMT (2200-0600 h). <br><br>CONCLUSIONS: The chronicity of sub-optimal sleep and sleep restriction is substantial during BMT and increased training demands exacerbate sleep disruption. As such, exploration of strategies is required to mitigate sleep-associated performance detriments and injury risk during BMT.<p /> <p>Language: en</p>",
language="en",
issn="1440-2440",
doi="10.1016/j.jsams.2022.01.008",
url="http://dx.doi.org/10.1016/j.jsams.2022.01.008"
}