Individual response to the end of Daylight Saving Time is largely dependent on habitual sleep duration

Abstract

The end of Daylight Saving Time provides a valuable opportunity to study the effects of a small, 1-h shift in local clock time in a naturalistic setting. Previous research suggests a delay in adjusting activity patterns by at least one week, possibly more. This study was designed to investigate the importance of prior sleep habits in predicting adaptation to the new schedule. One hundred and twenty participants completed the Pittsburgh Sleep Diary for six days before and six days after the October, UK transition (2010). A subsample (n = 35) also wore activity watches throughout the study. Adherence to the external clock by adjusting bed times and rise times was apparent on the first night, but difficulties in following this timing on subsequent nights, along with deterioration in sleep latency and efficiency, point to a delay in full adjustment, particularly for those who habitually sleep for less than 7.5 h/night.

Keywords:

• Daylight Saving Time
• habitual sleep
• sleep deprivation
• sleep disturbance