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Published on: August 8, 2019
Transitions into and out of daylight saving time compromise sleep and the rest-activity cycles
Tuuli A Lahti1, Sami Leppämäki, Jouko Lönnqvist
1Department of Mental Health and Alcohol Research, National Public Health Institute, Helsinki, Finland. tuuli.lahti@ktl.fi
Background:
The aim of this study was to analyze the effects of transition out of and into daylight saving time on the rest-activity cycles and sleep. Rest-activity cycles of nine healthy participants aged 20 to 40 years were measured around transitions out of and into daylight saving time on fall 2005 and spring 2006 respectively. Rest-activity cycles were measured using wrist-worn accelerometers. The participants filled in the Morningness-Eveningness and Seasonal Pattern Assessment Questionnaires before starting the study and kept a sleep diary during the study.
Results:
Fall transition was more disturbing for the more morning type and spring transition for the more evening type of persons. Individuals having a higher global seasonality score suffered more from the transitions.
Conclusion:
Transitions out of and into daylight saving time enhanced night-time restlessness and thereby compromised the quality of sleep.
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