What your resting heart rate REALLY should be at your age – and whether you should worry about what your smartwatch is telling you

Resting heart rate has long been considered a crucial health measure that can predict whether you are vulnerable to heart attack, stroke and lung disease.

The lower the score, the fitter you are, because the organ works efficiently to pump blood through your body when you are not exercising.

Now millions of us will know our magic number every minute of every day thanks to the smartwatches that cling to our wrists.

Some devices even provide alerts if the number exceeds a certain level.

But experts are cautious, saying the resting heart rate we see on our tracker isn’t as reliable an indicator of heart health as you might think.

Although the NHS suggests that a resting heart rate of between 60 and 100 beats per minute (bpm) is normal for adults, studies show that the ideal figure can vary depending on age.

One study found that men in their 50s with a heart rate above 75 beats per minute were twice as likely to die within the next 20 years, compared to men with a heart rate of 55 beats per minute or less.

The results also suggested that each additional bpm was associated with a three percent higher risk of death, a one percent higher risk of cardiovascular disease and a two percent increase in coronary heart disease.

Resting heart rate, the measure of how many times the vital organ beats per minute, is considered a crucial health metric and why a dozen smart devices now offer to track it

Meanwhile, data from the US Centers for Disease Prevention and Control (CDC) suggested that optimal heart condition means having a bpm of less than 60, roughly between 47 and 57.

It is thought that only about 10 percent of people fit into this category, most of whom are professional athletes.

Other figures suggest that a resting athletic heart rate for men aged 18 to 25 is between 40 and 52 beats per minute, while the equivalent figure for men over 65 is 52 to 55 beats per minute.

The average figure for men of all ages is a BPM in the low 70s, while people in poor or below average health are considered to have a BPM in the high 70s or above 80.

For women, an athletic woman aged 18 to 25 would achieve a resting pace of 40-48, while an athletic woman aged 65 and over would achieve 52-55 beats per minute.

An average result for women was 74-78 bpm on the younger end of the scale and 73-76 on the older end. Like men, a BPM above 70 or above 80 for women was considered below average or poor.

While 60-100 bpm is the normal range for adults, and many smart watches will tell you this is healthy, the general consensus is that the lower someone falls within that scale, the better.

For example, a resting pace of over 100 is considered far too fast for most people and could be a sign of something abnormal in the body.

Studies suggest that people with lower RHRs tend to have better heart health because they are generally healthier, while people with higher results are more likely to have risk factors for heart disease such as high blood pressure or obesity.

Experts are keen to point out that individuals vary, and some people will have different ‘normal’ resting heart rates, especially if they have pre-existing heart disease.

Heart rate variability (HRV), the term for variation in the time between heartbeats, is also a track for heart health in smart devices.

Some experts consider a high HRV as important as resting heart rate because it represents the organ’s ability to respond quickly to the demands placed on the body.

HRV naturally decreases as people age. Healthier people in their early twenties have an HRV of about 50 to 105 milliseconds, while in 60-65 year olds it is normally between 25 and 45 milliseconds.

Despite smart health devices giving us the ability to monitor heart health, experts warn against becoming too dependent on the devices as they have their faults.

Most wearables track heart rate using a small sensor on the back of the device. But this means that not wearing it tight enough – or wearing it too tight – can affect the accuracy of the data.

Additionally, people with darker skin and those with tattoos on their wrists may also experience more inaccurate results.

This is because darker skin tones absorb more light, which in turn can interfere with the green light the devices use to measure heart rate.

The same problem applies to tattoos around the wrist, because the substances that give them color also absorb light.

While some warning signs (pictured) are easy to spot – such as severe chest pain – others are vaguer and harder to pinpoint

In addition, some devices disable heart rate monitoring functions when the battery is low to save energy.

Finally, as with any device, failures can occur due to manufacturing or software errors, damage, or simple wear and tear.

It is for these reasons that doctors urge people with symptoms of heart problems to talk to a doctor, even if their smart device gives normal readings.

A device-safe way for people to check their resting heart rate is through the following exercise.

Place your index and middle fingers on the inside of your wrist or on one side of the neck, just below the jaw.

Once you find your heart rate, count the number of beats over the next 60 seconds to get a bpm figure.

To get the most accurate results, people are recommended to perform this test at rest, either sitting or lying down.

Experts also recommend not drinking coffee or nicotine before measuring your heart rate, as these substances can artificially increase the heart rate.

For accuracy, perform the test at the same time every day to get an average over time.

Another heart health tool that is often measured is the target heart rate (THR), a measure of how fast the organ should beat during exercise.

THR is first calculated by subtracting your age from 220 beats per minute and then taking this figure and figuring out what 50 and 70 percent of this is.

For example, a 50-year-old has a THR between 85 and 119 bpm.

Some experts increase this to between 50 and 85 percent of 220 bpm minus age, although the 50 to 70 percent range is recommended by the British Heart Foundation (BHF), which also has a free tool that you can use to find out yours.

Those who want to keep their heart fit use a THR range to ensure they are performing the optimal level of exercise. For example, a jogger who doesn’t reach his THR while running knows he needs to increase the pace.

Training with a THR above the recommended upper limit can be dangerous.

Those who do not have a smart device to monitor their heart rate during exercise are instead advised to take the so-called ‘talk test’ while exercising.

If you can still talk during the exercise, but also feel warm and breathe a little heavier than normal, you are working at the right pace.

But if you can’t talk at all, you might be doing too much.

As always, clinicians urge people to listen to their bodies and stop if an exercise makes them uncomfortable.

Although not as accurate as specific medical devices, experts say devices that measure heart rate can be useful because patients can be inspired to see a doctor for advice and any potentially worrying results can be properly investigated.