With winter now behind us and the longer days of summer looming comes the annual switch to daylight saving time.
According to Swinburne Associate Professor Greg Murray, who studies circadian rhythms in mood disorders, the days and weeks after the changeover can create sleep problems as our bodies adjust to the change in the sleep-wake rhythm.
"Daylight saving is designed primarily to save energy by shifting human behaviors more towards the light phase of the day," Murray said. "But adjusting to the switch can cause sleep disturbances."
Initially there is an acute sleep deprivation of one hour. "On top of the chronic sleep deprivation that many people suffer, this additional loss of sleep appears to cause decreased alertness, concentration and mental performance," Murray said.
According to some studies, this sleep loss is to blame for the apparent increase in traffic accidents and heart attacks in the week after the change.
"Until our body clock realizes the change has happened, we are sleeping at the wrong circadian phase, causing more disturbed sleep. People who are habitually more night-owlish, including adolescents, may take weeks to get in synch," Murray said.
However, once the body has adjusted the benefits start to accrue.
"We have more daylight time in which to exercise, socialise and get some sunlight exposure, which are good for mental health and wellbeing," Murray said.
To help manage the change he offers the following tips:
• Plan. It is difficult to go to bed earlier, so plan for the fact that you may be a bit sleep deprived on the first days after the switch. Leave early for work/school so you aren't rushing in traffic. If sleep deprivation leaves you irritable, watch your interactions with others.
• Adjust. It is important that the body clock advances to synchronise with the earlier sleep wake cycle. We can encourage this by getting light exposure early in the day. This is particularly important for adolescents and other night owls.
• Celebrate. Humans are social animals. More daylight time for exercise and socialisation is an opportunity to increase wellbeing and bed down positive new habits.