Too hot to sleep? Here's why 11 January 2013 Bushfires are quite
appropriately dominating our nation's concerns during the
current Australian heatwave. But for many, the struggle to sleep
through soaring temperatures is a personal inferno that
dominates conversation around offices and homes across the
country. Sleep and body control of temperature
(thermoregulation) are intimately connected. Core body
temperature follows a 24-hour cycle linked with the sleep-wake
rhythm. Body temperature decreases during the night-time sleep
phase and rises during the wake phase. Sleep is most likely to
occur when core temperature decreases, and much less likely to
occur during the rises. Our hands and feet play a key role in
facilitating sleep as they permit the heated blood from the
central body to lose heat to the environment through the skin
surface. The sleep hormone melatonin plays an important part of
the complex loss of heat through the peripheral parts of the
body. At sleep onset, core body temperature falls but peri