see also:

• physiology of sleep
• insomnia
• fatigue
• stress
• Coping with shift work
• managing jet lag and your body clock

• sleep disorders, excessive daytime sleepiness and dangers of driving with its legal ramifications:
  • Australian Roads
  • Australasian Sleep Association
• perhaps your body clock is set early in life and inherited from your mother as with zebra fish
• daylight savings and sleep disruption
• caffeine and guarana helps drivers stay alert and the guarana effect starts at ~1hr and lasts for ~5hrs

• sleep hygiene includes a number of social & behavioural interventions:
  • routines that incorporate the following techniques will help even older people, whatever their residential setting, have a better sleep:
    • establish sleep/wake activity regulation:
      • get up at the same time each day regardless of the amount of sleep that night - avoid over-sleeping
      • going to bed at a constant time is not as important, but might help
      • avoid daytime naps esp. in late afternoon as total sleep hours is preserved so night sleep will be less - restrict to 10-15min afternoon powernaps
      • exercise regularly but at least 6 hours before bedtime
    • create an optimal sleep setting:
      • use bed only for sleep & sex, not for eating, reading or watching television - avoid excessive time in bed
      • bedroom should be comfortable & quiet & not the focus of arguments, anger or distress
      • indulge in relaxing evening activities do not do exercise late in evening
      • avoid alerting and stressful ruminations before bedtime
      • avoid stimulants such as caffeine & nicotine for 2-3hrs before going to bed (some say no caffeine after lunch and no nicotine after dinner)
      • avoid large evening meal
      • reduce excessive alcohol intake
      • if unable to sleep, avoid clock watching, get up and do something
    • sleep promoting adjuvants:
      • light snack or warm bath before bed
      • engage in quiet activities before sleep eg. reading

• disrupts sleep cycles and ability to get to sleep
• it is likely that it disrupts the usual menstrual cycles linked to the moon phases
• a 2025 study showed those most exposed to night time light had a 56% higher chance of heart failure and 47% more likely to have a heart attack and that women and younger people were especially vulnerable to the impact of light exposure at night - women exposed to high levels of night light had similar heart failure risks to men, which is unusual because women typically have some natural protection against heart disease ¹⁾