Raksha Jaipurkar1, S S Mahapatra2, Saurabh Bobdey3, Chitra Banerji4. 1. Associate Professor, Department of Physiology, Armed Forces Medical College, Pune, 411040 India. 2. Head of Department, Space and Environmental Physiology, Institute of Aerospace Medicine, Bengaluru, India. 3. Classified Specialist (Community Medicine), O/o DGMS (Navy), New Delhi, India. 4. Col Med, HQ 2 Corps, C/o 56 APO, India.
Abstract
BACKGROUND: The combat naval vessels require continuous operational preparedness for guarding the vast coastline. Sailors onboard these ships are at risk for sleep deprivation. Sailors may be vulnerable to chronic fatigue; and decreased performance, vigilance, and cognitive functioning owing to sleep debt, which may affect safety during tactical operations and while transportation of ships. In this study we assessed the work-rest pattern and level of alertness during sailing and non sailing days. METHODS: Thirty-two male participants maintained a 24-h sleep and activity log for 5 days. Furthermore, qualitative gross motor activity was recorded using an actiwatch during these 5 days. Participants also completed four test sessions of personal digital assistant (PDA) based psychomotor vigilance task (PVT) test: pre-sleep, post-sleep, pre-work, and post-work. A comparison of data was performed using the Wilcoxon signed-rank test. RESULTS: Sailors received approximately 1 h less of rest while sailing. There was a significant difference in bedtime, wake-up time, total sleep time, sleep onset latency (SOL), wake up after sleep onset (WASO), and the number of awakenings during the non-sailing and the sailing days. PVT data showed significantly higher reaction times during the sailing days on pre-work and post-sleep sessions. CONCLUSION: Our study shows that although the sailors are not getting sufficient restorative sleep while sailing as compared to non-sailing days, this is not affecting their cognitive functioning while working.
BACKGROUND: The combat naval vessels require continuous operational preparedness for guarding the vast coastline. Sailors onboard these ships are at risk for sleep deprivation. Sailors may be vulnerable to chronic fatigue; and decreased performance, vigilance, and cognitive functioning owing to sleep debt, which may affect safety during tactical operations and while transportation of ships. In this study we assessed the work-rest pattern and level of alertness during sailing and non sailing days. METHODS: Thirty-two male participants maintained a 24-h sleep and activity log for 5 days. Furthermore, qualitative gross motor activity was recorded using an actiwatch during these 5 days. Participants also completed four test sessions of personal digital assistant (PDA) based psychomotor vigilance task (PVT) test: pre-sleep, post-sleep, pre-work, and post-work. A comparison of data was performed using the Wilcoxon signed-rank test. RESULTS: Sailors received approximately 1 h less of rest while sailing. There was a significant difference in bedtime, wake-up time, total sleep time, sleep onset latency (SOL), wake up after sleep onset (WASO), and the number of awakenings during the non-sailing and the sailing days. PVT data showed significantly higher reaction times during the sailing days on pre-work and post-sleep sessions. CONCLUSION: Our study shows that although the sailors are not getting sufficient restorative sleep while sailing as compared to non-sailing days, this is not affecting their cognitive functioning while working.
Authors: Sean P A Drummond; Amanda Bischoff-Grethe; David F Dinges; Liat Ayalon; Sara C Mednick; M J Meloy Journal: Sleep Date: 2005-09 Impact factor: 5.849
Authors: Sonia Ancoli-Israel; Roger Cole; Cathy Alessi; Mark Chambers; William Moorcroft; Charles P Pollak Journal: Sleep Date: 2003-05-01 Impact factor: 5.849
Authors: Fiona Kerkamm; Dorothee Dengler; Matthias Eichler; Danuta Materzok-Köppen; Lukas Belz; Felix Alexander Neumann; Birgit Christiane Zyriax; Volker Harth; Marcus Oldenburg Journal: Int J Environ Res Public Health Date: 2021-12-23 Impact factor: 3.390