A normal heart rate while sleeping for most healthy adults typically ranges between 40 and 60 beats per minute (bpm). This rate is generally 20-30% lower than the resting heart rate during waking hours. Factors such as age, fitness level, health status, and sleep stages can influence this range. For highly fit individuals or athletes, sleeping heart rates can be even lower, around 30 to 40 bpm. During REM sleep, the heart rate may fluctuate due to dream activity, while during deep sleep it tends to be at its lowest.
