When it comes to resting heart rate (RHR), there is no such thing as “normal”, a study published in Scientific Reports suggests.
Resting heart rates vary by as much as 70 beats per minute (bpm), but it remains unclear what can be considered as "normal" and the variations from this norm mean for health.
Having analyzed data from 50,000 people, the National Health and Nutrition Examination Survey stated that the average RHR for adults is 72 bpm. Meanwhile, the American Heart Association (AHA) found that an RHR of 60–100 bpm normal for adults.
However, while higher rates may mean increased cardiovascular risk, one study revealed that people with an RHR below 65 bpm could be at risk too.
The study "Association of resting heart rate and its change with incident cardiovascular events in the middle-aged and older Chinese" explains that “a single measurement of heart rate provides very little useful information about the current health of an individual, unless well out of the expected range of normal.”
The researchers showed that a significant change in RHR over the three-year follow-up period led to higher cardiovascular risk. They performed a “long view of individual changes in cardiac performance.”
Their findings were based on data from 92,457 adults across 50 states. There was a heart rate monitor for each participant for at least two days each week for at least 35 weeks between March 2016 and February 2018. Each day, they wore it for at least 20 hours.
The study authors used wearable sensors because they provide a “unique opportunity to better understand how RHR varies over time for and between individuals over the span of days, weeks, years, and, eventually, lifetimes.”
