When does the body temperature usually start to rise according to circadian rhythms?

The body temperature typically begins to rise in the early morning as part of the natural circadian rhythms. Circadian rhythms are physiological processes that follow a roughly 24-hour cycle, influenced by external cues like light and darkness.

As night transitions to day, the body prepares for wakefulness. This includes a rise in core body temperature, which is associated with increased metabolic activity and alertness as the body gears up for daily activities. This temperature increase generally begins a couple of hours before individuals wake up and peaks during the day, which supports cognitive functions and physical performance.

The early morning rise in temperature is an essential part of the overall circadian rhythm, which also includes fluctuations in other biological functions such as hormone levels and sleep-wake cycles. This physiological response is critical for maintaining proper alertness and functioning during the day.