Daylight Saving Time

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Timo Partonen - One of the best experts on this subject based on the ideXlab platform.

  • work related accidents and Daylight Saving Time in finland
    Occupational Medicine, 2011
    Co-Authors: Tuuli Lahti, Jari Haukka, J Sysiaho, Timo Partonen
    Abstract:

    BACKGROUND: Recent research has indicated that transitions into and out of Daylight Saving Time (DST) unbalance the physiological circadian rhythm and may lead to sleep disturbance. Sleep deprivation may have negative effects on motivation, attention and alertness and thus it is possible that transitions into and out of DST may increase accident rates. AIMS: To explore the impact of DST transitions on the number of occupational accidents in Finland. METHODS: For the study, we analysed all occupational accidents that happened in Finland 1 week before and 1 week after DST transitions during the years 2002-06. RESULTS: Transitions into and out of DST did not significantly increase the number of occupational accidents. CONCLUSIONS: It seems that sleep deprivation after DST transition is not harmful enough to impact on occupational accident rates. Language: en

  • Daylight Saving Time transitions and road traffic accidents
    Journal of Environmental and Public Health, 2010
    Co-Authors: Tuuli Lahti, Esa Nysten, Pekka Sulander, Jari Haukka, Timo Partonen
    Abstract:

    Circadian rhythm disruptions may have harmful impacts on health. Circadian rhythm disruptions caused by jet lag compromise the quality and amount of sleep and may lead to a variety of symptoms such as fatigue, headache, and loss of attention and alertness. Even a minor change in Time schedule may cause considerable stress for the body. Transitions into and out of Daylight Saving Time alter the social and environmental timing twice a year. According to earlier studies, this change in Time-schedule leads to sleep disruption and fragmentation of the circadian rhythm. Since sleep deprivation decreases motivation, attention, and alertness, transitions into and out of Daylight Saving Time may increase the amount of accidents during the following days after the transition. We studied the amount of road traffic accidents one week before and one week after transitions into and out of Daylight Saving Time during years from 1981 to 2006. Our results demonstrated that transitions into and out of Daylight Saving Time did not increase the number of traffic road accidents.

  • Daylight Saving Time transitions and hospital treatments due to accidents or manic episodes
    BMC Public Health, 2008
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Timo Partonen
    Abstract:

    Background Daylight Saving Time affects millions of people annually but its impacts are still widely unknown. Sleep deprivation and the change of circadian rhythm can trigger mental illness and cause higher accident rates. Transitions into and out of Daylight Saving Time changes the circadian rhythm and may cause sleep deprivation. Thus it seems plausible that the prevalence of accidents and/or manic episodes may be higher after transition into and out of Daylight Saving Time. The aim of this study was to explore the effects of transitions into and out of Daylight Saving Time on the incidence of accidents and manic episodes in the Finnish population during the years of 1987 to 2003.

  • Transitions into and out of Daylight Saving Time compromise sleep and the rest-activity cycles
    BMC Physiology, 2008
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    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.

  • transitions into and out of Daylight Saving Time compromise sleep and the rest activity cycles
    BMC Physiology, 2008
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    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. 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. Transitions out of and into Daylight Saving Time enhanced night-Time restlessness and thereby compromised the quality of sleep.

Tuuli Lahti - One of the best experts on this subject based on the ideXlab platform.

  • work related accidents and Daylight Saving Time in finland
    Occupational Medicine, 2011
    Co-Authors: Tuuli Lahti, Jari Haukka, J Sysiaho, Timo Partonen
    Abstract:

    BACKGROUND: Recent research has indicated that transitions into and out of Daylight Saving Time (DST) unbalance the physiological circadian rhythm and may lead to sleep disturbance. Sleep deprivation may have negative effects on motivation, attention and alertness and thus it is possible that transitions into and out of DST may increase accident rates. AIMS: To explore the impact of DST transitions on the number of occupational accidents in Finland. METHODS: For the study, we analysed all occupational accidents that happened in Finland 1 week before and 1 week after DST transitions during the years 2002-06. RESULTS: Transitions into and out of DST did not significantly increase the number of occupational accidents. CONCLUSIONS: It seems that sleep deprivation after DST transition is not harmful enough to impact on occupational accident rates. Language: en

  • Daylight Saving Time transitions and road traffic accidents
    Journal of Environmental and Public Health, 2010
    Co-Authors: Tuuli Lahti, Esa Nysten, Pekka Sulander, Jari Haukka, Timo Partonen
    Abstract:

    Circadian rhythm disruptions may have harmful impacts on health. Circadian rhythm disruptions caused by jet lag compromise the quality and amount of sleep and may lead to a variety of symptoms such as fatigue, headache, and loss of attention and alertness. Even a minor change in Time schedule may cause considerable stress for the body. Transitions into and out of Daylight Saving Time alter the social and environmental timing twice a year. According to earlier studies, this change in Time-schedule leads to sleep disruption and fragmentation of the circadian rhythm. Since sleep deprivation decreases motivation, attention, and alertness, transitions into and out of Daylight Saving Time may increase the amount of accidents during the following days after the transition. We studied the amount of road traffic accidents one week before and one week after transitions into and out of Daylight Saving Time during years from 1981 to 2006. Our results demonstrated that transitions into and out of Daylight Saving Time did not increase the number of traffic road accidents.

  • Daylight Saving Time transitions and hospital treatments due to accidents or manic episodes
    BMC Public Health, 2008
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Timo Partonen
    Abstract:

    Background Daylight Saving Time affects millions of people annually but its impacts are still widely unknown. Sleep deprivation and the change of circadian rhythm can trigger mental illness and cause higher accident rates. Transitions into and out of Daylight Saving Time changes the circadian rhythm and may cause sleep deprivation. Thus it seems plausible that the prevalence of accidents and/or manic episodes may be higher after transition into and out of Daylight Saving Time. The aim of this study was to explore the effects of transitions into and out of Daylight Saving Time on the incidence of accidents and manic episodes in the Finnish population during the years of 1987 to 2003.

  • Transitions into and out of Daylight Saving Time compromise sleep and the rest-activity cycles
    BMC Physiology, 2008
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    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.

  • transitions into and out of Daylight Saving Time compromise sleep and the rest activity cycles
    BMC Physiology, 2008
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    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. 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. Transitions out of and into Daylight Saving Time enhanced night-Time restlessness and thereby compromised the quality of sleep.

Jouko Lonnqvist - One of the best experts on this subject based on the ideXlab platform.

  • Daylight Saving Time transitions and hospital treatments due to accidents or manic episodes
    BMC Public Health, 2008
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Timo Partonen
    Abstract:

    Background Daylight Saving Time affects millions of people annually but its impacts are still widely unknown. Sleep deprivation and the change of circadian rhythm can trigger mental illness and cause higher accident rates. Transitions into and out of Daylight Saving Time changes the circadian rhythm and may cause sleep deprivation. Thus it seems plausible that the prevalence of accidents and/or manic episodes may be higher after transition into and out of Daylight Saving Time. The aim of this study was to explore the effects of transitions into and out of Daylight Saving Time on the incidence of accidents and manic episodes in the Finnish population during the years of 1987 to 2003.

  • Transitions into and out of Daylight Saving Time compromise sleep and the rest-activity cycles
    BMC Physiology, 2008
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    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.

  • transitions into and out of Daylight Saving Time compromise sleep and the rest activity cycles
    BMC Physiology, 2008
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    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. 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. Transitions out of and into Daylight Saving Time enhanced night-Time restlessness and thereby compromised the quality of sleep.

  • transition to Daylight Saving Time reduces sleep duration plus sleep efficiency of the deprived sleep
    Neuroscience Letters, 2006
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    Abstract Daylight Saving Time (DST) is widely adopted. We explored the effects of transition to Daylight Saving Time on sleep. With the use of wrist-worn accelerometers, we monitored the rest-activity cycles on a sample of 10 healthy adults for 10 days around the transition to summer Time. Identical measurement protocols were carried out twice on the same individuals during the transitions in the years of 2003 and 2004, yielding data on 200 person-days for analysis. Both sleep duration and sleep efficiency were reduced after the transition both years. After the transition sleep Time was shortened by 60.14 min (P

  • Transition into Daylight Saving Time influences the fragmentation of the rest-activity cycle
    Journal of Circadian Rhythms, 2006
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Sami Leppämäki, Sanna-maria Ojanen, Annamari Tuulio-henriksson, Timo Partonen
    Abstract:

    Background Daylight Saving Time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into Daylight Saving Time on the circadian rhythm of activity. Methods We monitored the rest-activity cycles with the use of wrist-worn accelerometer on a sample of ten healthy adults for ten days around the transition into summer Time. Identical protocols were carried out on the same individuals in two consecutive years, yielding data on 200 person-days for analysis in this study. Results There was no significant effect on the rest-activity cycle in the sample as a whole. Fragmentation of the rest-activity cycle was enhanced in a subgroup of persons having sleep for eight hours or less (P = 0.04) but reduced in those who preferred to sleep for more than eight hours per night (P = 0.05). The average level of motor activity was increased in persons having the morning preference for daily activity patterns (P = 0.01). Conclusion Transition into Daylight Saving Time may have a disruptive effect on the rest-activity cycle in those healthy adults who are short-sleepers or more of the evening type.

Sami Leppämäki - One of the best experts on this subject based on the ideXlab platform.

  • Transitions into and out of Daylight Saving Time compromise sleep and the rest-activity cycles
    BMC Physiology, 2008
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    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.

  • transitions into and out of Daylight Saving Time compromise sleep and the rest activity cycles
    BMC Physiology, 2008
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    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. 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. Transitions out of and into Daylight Saving Time enhanced night-Time restlessness and thereby compromised the quality of sleep.

  • transition to Daylight Saving Time reduces sleep duration plus sleep efficiency of the deprived sleep
    Neuroscience Letters, 2006
    Co-Authors: Tuuli Lahti, Jouko Lonnqvist, Sami Leppämäki, Timo Partonen
    Abstract:

    Abstract Daylight Saving Time (DST) is widely adopted. We explored the effects of transition to Daylight Saving Time on sleep. With the use of wrist-worn accelerometers, we monitored the rest-activity cycles on a sample of 10 healthy adults for 10 days around the transition to summer Time. Identical measurement protocols were carried out twice on the same individuals during the transitions in the years of 2003 and 2004, yielding data on 200 person-days for analysis. Both sleep duration and sleep efficiency were reduced after the transition both years. After the transition sleep Time was shortened by 60.14 min (P

  • Transition into Daylight Saving Time influences the fragmentation of the rest-activity cycle
    Journal of Circadian Rhythms, 2006
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Sami Leppämäki, Sanna-maria Ojanen, Annamari Tuulio-henriksson, Timo Partonen
    Abstract:

    Background Daylight Saving Time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into Daylight Saving Time on the circadian rhythm of activity. Methods We monitored the rest-activity cycles with the use of wrist-worn accelerometer on a sample of ten healthy adults for ten days around the transition into summer Time. Identical protocols were carried out on the same individuals in two consecutive years, yielding data on 200 person-days for analysis in this study. Results There was no significant effect on the rest-activity cycle in the sample as a whole. Fragmentation of the rest-activity cycle was enhanced in a subgroup of persons having sleep for eight hours or less (P = 0.04) but reduced in those who preferred to sleep for more than eight hours per night (P = 0.05). The average level of motor activity was increased in persons having the morning preference for daily activity patterns (P = 0.01). Conclusion Transition into Daylight Saving Time may have a disruptive effect on the rest-activity cycle in those healthy adults who are short-sleepers or more of the evening type.

  • transition into Daylight Saving Time influences the fragmentation of the rest activity cycle
    Journal of Circadian Rhythms, 2006
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Sami Leppämäki, Sanna-maria Ojanen, Annamari Tuuliohenriksson, Timo Partonen
    Abstract:

    Daylight Saving Time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into Daylight Saving Time on the circadian rhythm of activity. We monitored the rest-activity cycles with the use of wrist-worn accelerometer on a sample of ten healthy adults for ten days around the transition into summer Time. Identical protocols were carried out on the same individuals in two consecutive years, yielding data on 200 person-days for analysis in this study. There was no significant effect on the rest-activity cycle in the sample as a whole. Fragmentation of the rest-activity cycle was enhanced in a subgroup of persons having sleep for eight hours or less (P = 0.04) but reduced in those who preferred to sleep for more than eight hours per night (P = 0.05). The average level of motor activity was increased in persons having the morning preference for daily activity patterns (P = 0.01). Transition into Daylight Saving Time may have a disruptive effect on the rest-activity cycle in those healthy adults who are short-sleepers or more of the evening type.

Jari Haukka - One of the best experts on this subject based on the ideXlab platform.

  • work related accidents and Daylight Saving Time in finland
    Occupational Medicine, 2011
    Co-Authors: Tuuli Lahti, Jari Haukka, J Sysiaho, Timo Partonen
    Abstract:

    BACKGROUND: Recent research has indicated that transitions into and out of Daylight Saving Time (DST) unbalance the physiological circadian rhythm and may lead to sleep disturbance. Sleep deprivation may have negative effects on motivation, attention and alertness and thus it is possible that transitions into and out of DST may increase accident rates. AIMS: To explore the impact of DST transitions on the number of occupational accidents in Finland. METHODS: For the study, we analysed all occupational accidents that happened in Finland 1 week before and 1 week after DST transitions during the years 2002-06. RESULTS: Transitions into and out of DST did not significantly increase the number of occupational accidents. CONCLUSIONS: It seems that sleep deprivation after DST transition is not harmful enough to impact on occupational accident rates. Language: en

  • Daylight Saving Time transitions and road traffic accidents
    Journal of Environmental and Public Health, 2010
    Co-Authors: Tuuli Lahti, Esa Nysten, Pekka Sulander, Jari Haukka, Timo Partonen
    Abstract:

    Circadian rhythm disruptions may have harmful impacts on health. Circadian rhythm disruptions caused by jet lag compromise the quality and amount of sleep and may lead to a variety of symptoms such as fatigue, headache, and loss of attention and alertness. Even a minor change in Time schedule may cause considerable stress for the body. Transitions into and out of Daylight Saving Time alter the social and environmental timing twice a year. According to earlier studies, this change in Time-schedule leads to sleep disruption and fragmentation of the circadian rhythm. Since sleep deprivation decreases motivation, attention, and alertness, transitions into and out of Daylight Saving Time may increase the amount of accidents during the following days after the transition. We studied the amount of road traffic accidents one week before and one week after transitions into and out of Daylight Saving Time during years from 1981 to 2006. Our results demonstrated that transitions into and out of Daylight Saving Time did not increase the number of traffic road accidents.

  • Daylight Saving Time transitions and hospital treatments due to accidents or manic episodes
    BMC Public Health, 2008
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Timo Partonen
    Abstract:

    Background Daylight Saving Time affects millions of people annually but its impacts are still widely unknown. Sleep deprivation and the change of circadian rhythm can trigger mental illness and cause higher accident rates. Transitions into and out of Daylight Saving Time changes the circadian rhythm and may cause sleep deprivation. Thus it seems plausible that the prevalence of accidents and/or manic episodes may be higher after transition into and out of Daylight Saving Time. The aim of this study was to explore the effects of transitions into and out of Daylight Saving Time on the incidence of accidents and manic episodes in the Finnish population during the years of 1987 to 2003.

  • Transition into Daylight Saving Time influences the fragmentation of the rest-activity cycle
    Journal of Circadian Rhythms, 2006
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Sami Leppämäki, Sanna-maria Ojanen, Annamari Tuulio-henriksson, Timo Partonen
    Abstract:

    Background Daylight Saving Time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into Daylight Saving Time on the circadian rhythm of activity. Methods We monitored the rest-activity cycles with the use of wrist-worn accelerometer on a sample of ten healthy adults for ten days around the transition into summer Time. Identical protocols were carried out on the same individuals in two consecutive years, yielding data on 200 person-days for analysis in this study. Results There was no significant effect on the rest-activity cycle in the sample as a whole. Fragmentation of the rest-activity cycle was enhanced in a subgroup of persons having sleep for eight hours or less (P = 0.04) but reduced in those who preferred to sleep for more than eight hours per night (P = 0.05). The average level of motor activity was increased in persons having the morning preference for daily activity patterns (P = 0.01). Conclusion Transition into Daylight Saving Time may have a disruptive effect on the rest-activity cycle in those healthy adults who are short-sleepers or more of the evening type.

  • transition into Daylight Saving Time influences the fragmentation of the rest activity cycle
    Journal of Circadian Rhythms, 2006
    Co-Authors: Tuuli Lahti, Jari Haukka, Jouko Lonnqvist, Sami Leppämäki, Sanna-maria Ojanen, Annamari Tuuliohenriksson, Timo Partonen
    Abstract:

    Daylight Saving Time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into Daylight Saving Time on the circadian rhythm of activity. We monitored the rest-activity cycles with the use of wrist-worn accelerometer on a sample of ten healthy adults for ten days around the transition into summer Time. Identical protocols were carried out on the same individuals in two consecutive years, yielding data on 200 person-days for analysis in this study. There was no significant effect on the rest-activity cycle in the sample as a whole. Fragmentation of the rest-activity cycle was enhanced in a subgroup of persons having sleep for eight hours or less (P = 0.04) but reduced in those who preferred to sleep for more than eight hours per night (P = 0.05). The average level of motor activity was increased in persons having the morning preference for daily activity patterns (P = 0.01). Transition into Daylight Saving Time may have a disruptive effect on the rest-activity cycle in those healthy adults who are short-sleepers or more of the evening type.