Circadian rhythm will cause you to be less alert during which time period?

Circadian rhythm will cause you to be less alert during which time period?

• A. Between one and five pm
• B. Early morning
• C. Late night
• D. Noon to 1 pm

Answer: (C)

Circadian rhythm is your body's 24-hour cycle that tells you when to be awake and when to sleep. In the dark, melatonin increases and body temperature drops, nudging you toward sleep. That natural drive to rest is strongest during late-night hours, so alertness is reduced and reaction times can slow. Driving then means you’re more likely to miss hazards or react slowly, which is why late night is when you’re least alert. If you have to drive at night, try to sleep well beforehand, take breaks, and consider a brief nap if safe to do so; caffeine can help temporarily, but it doesn’t replace sleep.

Circadian rhythm is your body's 24-hour cycle that tells you when to be awake and when to sleep. In the dark, melatonin increases and body temperature drops, nudging you toward sleep. That natural drive to rest is strongest during late-night hours, so alertness is reduced and reaction times can slow. Driving then means you’re more likely to miss hazards or react slowly, which is why late night is when you’re least alert. If you have to drive at night, try to sleep well beforehand, take breaks, and consider a brief nap if safe to do so; caffeine can help temporarily, but it doesn’t replace sleep.