Your heart rate during sleep is typically 10-20% lower than your daytime resting heart rate. If your daytime resting heart rate is 65 bpm, expect your sleeping heart rate to sit around 50-58 bpm. This dip is normal and healthy. It reflects your parasympathetic nervous system taking over during rest, allowing your heart to slow down and your body to focus on recovery.
Sleeping vs Resting Heart Rate
“Resting heart rate” as measured by Apple Watch is typically your lowest heart rate during waking hours of inactivity. Your sleeping heart rate goes even lower. Apple Watch tracks both. The lowest point usually occurs during deep sleep in the first half of the night, when parasympathetic activity peaks.
During REM sleep, heart rate can increase and become more variable, sometimes approaching waking levels. This is normal. The overall pattern across the night, a gradual decline followed by a slight rise toward morning, is what a healthy sleep looks like from a heart rate perspective.
What Is Normal by Age
| Age | Typical Sleeping HR | Typical Resting HR |
|---|---|---|
| 18-25 | 45-65 bpm | 55-75 bpm |
| 26-35 | 45-65 bpm | 58-78 bpm |
| 36-45 | 48-68 bpm | 60-80 bpm |
| 46-55 | 48-70 bpm | 62-82 bpm |
| 56-65 | 50-72 bpm | 60-80 bpm |
| 65+ | 50-72 bpm | 60-78 bpm |
These are approximate ranges for the general population. Athletes and very fit individuals will be at the lower end or below. See the resting heart rate by age chart for more detailed ranges by fitness level.
What Disrupts Sleeping Heart Rate
Alcohol is one of the most significant disruptors. Even moderate amounts raise sleeping heart rate substantially, often by 5-10+ bpm. Alcohol suppresses deep sleep and keeps the sympathetic nervous system more active throughout the night.
Late meals can elevate heart rate as your body diverts blood flow to digestion. Eating within 2-3 hours of bedtime tends to produce a measurably higher overnight heart rate.
Stress and anxiety activate the sympathetic nervous system, keeping heart rate elevated even during sleep. This is one reason why tracking sleeping heart rate is valuable. It reveals stress that you might not consciously register.
Overtraining produces a paradoxical effect. Too much exercise without adequate recovery raises, rather than lowers, your overnight heart rate. A sudden rise in sleeping heart rate despite consistent training is an early warning sign of overtraining.
Illness. A rising sleeping heart rate can signal oncoming illness before symptoms appear. Your immune system’s inflammatory response elevates heart rate, and this is often detectable overnight 1-2 days before you feel sick.
Why It Matters
Sleeping heart rate is one of the most reliable indicators of recovery and overall cardiovascular health because it removes the noise of daily activity, caffeine, and momentary stress. Tracking the trend reveals patterns that daytime measurements miss. Beyond heart rate, sleep quality also impacts your cardio fitness. See how sleep affects your VO2 Max.
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Download for iOSFrequently Asked Questions
What should my heart rate be while sleeping?
Most healthy adults have a sleeping heart rate between 40-60 bpm, which is typically 10-20 bpm lower than their daytime resting rate. Very fit individuals may drop into the high 30s. Heart rate usually reaches its lowest point during deep sleep in the middle of the night.
Why is my heart rate high while sleeping?
Common causes include alcohol consumption (even moderate amounts), stress or anxiety, illness or infection, overtraining, sleep apnea, dehydration, caffeine consumed too late in the day, and sleeping in a warm room. A consistently elevated sleeping heart rate that doesn't resolve may warrant medical attention.
Is it normal for heart rate to drop below 50 while sleeping?
Yes, for many people. Athletes and physically fit individuals commonly see sleeping heart rates in the 40s or even high 30s. This is generally a sign of good cardiovascular fitness. However, if you experience dizziness, fainting, or extreme fatigue alongside a very low heart rate, consult a doctor.
What does Apple Watch resting heart rate measure?
Apple Watch calculates resting heart rate from the lowest sedentary readings throughout the day while you're awake — it's not the same as sleeping heart rate. It uses background measurements when the accelerometer detects you're still. Your resting heart rate value may change during the day as more measurements are collected.