A runner’s resting heart rate typically falls between 40 and 60 beats per minute (bpm), well below the 60 to 100 bpm range considered normal for most adults. The more consistently you run, the lower your resting heart rate tends to drop, because your heart becomes stronger and more efficient at pumping blood with each beat.
Typical Ranges by Fitness Level
For a non-athlete adult sitting calmly, a resting heart rate anywhere from 60 to 100 bpm is normal. Regular runners and other endurance athletes commonly see rates in the 40s and 50s. Elite endurance athletes sometimes dip into the high 30s, though that’s rare and largely influenced by genetics.
Where you fall within those ranges depends on your age, sex, and training volume. Women tend to have slightly higher resting heart rates than men at every fitness level, typically about 4 to 5 bpm higher. This is partly because women generally have smaller hearts and lower blood volume, so the heart needs to beat more frequently to circulate enough oxygen.
Here’s a general breakdown for trained athletes:
- Men ages 18 to 35: 49 to 55 bpm
- Men ages 36 to 55: 50 to 57 bpm
- Men ages 56 and older: 50 to 56 bpm
- Women ages 18 to 35: 54 to 60 bpm
- Women ages 36 to 55: 54 to 60 bpm
- Women ages 56 and older: 54 to 59 bpm
If you’re a recreational runner rather than a competitive one, your resting rate will likely sit a bit higher, perhaps in the low 60s. That’s still a sign of good cardiovascular fitness. Dropping from, say, 72 bpm to 62 bpm over several months of consistent training is a meaningful improvement, even if you never reach the 40s.
Why Running Lowers Your Heart Rate
The simplest explanation is that endurance training makes your heart a bigger, more powerful pump. Over months of regular running, the left ventricle (the heart’s main pumping chamber) gradually enlarges and its walls thicken slightly. This is called eccentric hypertrophy, and it’s a normal, healthy adaptation. A larger chamber fills with more blood per beat, so the heart doesn’t need to beat as often to deliver the same amount of oxygen to your body.
That’s only part of the picture. Your nervous system also adapts. The vagus nerve, which acts as a brake on your heart rate, becomes more active in trained runners. This increased “vagal tone” keeps the heart beating more slowly at rest. Research published in the American Heart Association’s journal Circulation also points to physical remodeling of the heart’s natural pacemaker cells. The right atrium, where those pacemaker cells sit, stretches in response to the increased blood flow that comes with training. That stretch appears to directly slow the rate at which those cells fire.
Genetics play a role too. Some people are born with naturally lower heart rates and larger cardiac chambers, which may give them a built-in advantage for endurance performance. So if your running partner has a resting rate of 42 and yours is 55 despite similar training, that doesn’t necessarily mean they’re fitter.
How to Measure It Accurately
Sit or lie down in a comfortable position for at least five minutes before taking your reading. You can use a chest strap, a smartwatch, or simply place two fingers on your wrist and count the beats for 30 seconds, then multiply by two.
Avoid measuring after exercise, caffeine, or a stressful event, as all of these can keep your heart rate elevated for up to two hours. The time of day doesn’t matter much, but consistency does. If you want to track trends over time, measure under the same conditions each day. Many runners check first thing in the morning, before getting out of bed, since that’s when external variables are lowest.
Using Resting Heart Rate to Track Fitness
Your resting heart rate is one of the easiest windows into your cardiovascular fitness. As your aerobic base improves over weeks and months of training, you should see a gradual downward trend. A drop of even a few beats per minute reflects real changes in how efficiently your heart works.
The reverse is also useful. A sudden rise in your resting heart rate can signal that something is off. An increase of 5 or more bpm that shows up on two or more consecutive mornings is a recognized sign of overtraining or accumulated fatigue. Illness, dehydration, poor sleep, and high stress can also bump it up temporarily. If your morning rate jumps and stays elevated for several days, it’s worth pulling back on training intensity until it returns to your baseline.
When a Low Heart Rate Is a Concern
A heart rate in the 40s or even high 30s is common in well-trained runners and, on its own, is not a problem. This is sometimes called “athlete’s heart,” and it resolves on its own if you stop training for an extended period. The heart gradually returns to a more typical size and rate.
The distinction between a healthy low heart rate and a problematic one comes down to symptoms. A runner with a resting rate of 38 who feels strong, recovers well, and has no issues during hard efforts has no reason for concern. But if a low heart rate comes with dizziness, fainting, unusual fatigue, or shortness of breath during activities that shouldn’t cause it, those symptoms point to a possible electrical or structural issue in the heart that warrants evaluation.
It’s also worth noting that very long pauses between heartbeats during sleep (common in endurance athletes) are usually benign but can occasionally overlap with heart rhythm disorders. If you notice your wearable device logging unusually long pauses or irregular rhythms overnight, that information is worth sharing with a cardiologist who has experience working with athletes, since the normal heart of a runner looks quite different from the normal heart of a sedentary person on standard screening tests.