A measurement on your fitness tracker that is usually ignored could be ‘the very best indicator of health in the world’ doctors have said.
Heart rate variability (HRV) is when the amount of time between each heartbeat fluctuates slightly.
And the degree of variability can be a crucial indicator of current or future health problems.
In general, a higher HRV is considered beneficial as it means there is greater variation between beats, meaning the organ is more resistant to stress.
Little or no variation in the time between heartbeats can indicate that the body is in ‘fight or flight mode’: the nervous system has detected a threat or stressor.
This can be caused by heart disease and mental health problems such as anxiety depression.
Studies have linked heart rate variability to increased and decreased risk of chronic diseases
Studies have shown that a higher HRV is associated with a lower risk of heart disease, while a low HRV is associated with high blood pressure and diabetes.
Heart rate variability should not be confused with the serious condition arrhythmia – when the heart beats with an irregular or abnormal rhythm.
In arrhythmia, which can lead to heart failure, stroke or cardiac arrest, the variance between the intervals is significantly greater: more than 0.12 seconds.
In a medical setting, doctors measure HRV using something called an electrocardiogram machine (also known as an ECG).
But up to 40 percent of smartwatches or personal fitness monitors measure HRV, according to Dr. George Lundberg, pathologist and editor of the online medical journal Medscape.
Some devices send real-time results back to a paired smartphone 24/7 — and more than 100 million Americans use the trackers.
More than 100 million Americans use smartwatches or personal fitness monitors, and up to 40 percent of smartwatches or personal fitness monitors measure HRV, which some doctors say is the “single best measure of health in the world.”
Experts have said that significant changes in HRV may be associated with a wide range of mental and physical conditions, including PTSD, sleep disorders, depression, cardiac arrhythmias, overexertion and certain medications.
Measured in milliseconds, the normal range for HRV averages below 100 milliseconds for children under 10 years of age. This decreases by about 10 milliseconds per decade lived.
Between 30 and 40 years old the average is 70 milliseconds; age 60-70 it is 40 milliseconds; and between 90 and 100 years it is 10 milliseconds.
Dr. Ross Hauser, a chronic pain doctor from Florida, said HRV is the optimal indicator of a range of things, including “whether or not you’re going to live a long life, whether or not you’re going to get sick.” in the near future, even if you sustain a sports injury.’
Between 30 and 40 years old the average HRV is 70 milliseconds and between 60 and 70 years old it is 40 milliseconds
This is thought to be because HRV illustrates how well the body can cope with physical and mental challenges. Constant stress and insufficient physiological recovery from this stress can make the nervous system ‘brittle’ and lead to a lower HRV.
Dr. George Lundberg, pathologist and managing editor for Medscape, emphasized the importance of the measurement in a recent editorial.
He wrote that HRV could be a “simple yet powerful tool that can be used to monitor overall health and well-being.”
HRV is controlled by a part of the nervous system called the autonomic nervous system, which regulates functions such as heart rate, blood pressure, breathing and digestion.
When your system is in fight-or-flight mode, the variation between heartbeats is typically smaller, but when the system is in a more relaxed state, HRV may be higher.
Medications and devices such as pacemakers can also affect HRV, distorting the results and sometimes showing a reduced HRV.
A low HRV can be a sign of current or future health problems because it shows that the body is struggling to cope with changing situations, such as stress, poor sleep, unhealthy diet, dysfunctional relationships, isolation or loneliness, and lack of exercise.
HRV score can be improved by managing stress, exercising regularly, eating a balanced diet, getting enough sleep and not smoking or drinking too much.
A “substantial and relatively old body of heart rhythm literature” links changes in HRV to a number of things, including “PTSD, occupational stress in physicians, sleep disorders, depression, various cardiac arrhythmias, fatigue, overexertion, medications, and age itself.” Dr. Lundberg wrote.
Proper study and sharing of HRV data will determine its usefulness, Dr. Lundberg added, as “credible research on this vast amount of data collected from wearables is lacking.”
Dr. Marcelo Campos, a Boston GP, cautioned “not to be too confident if you have a high HRV, or too worried if your HRV is low,” because the correlation between HRV and how well the body functions continues to require more research. research.
“Think of HRV as another way you can get your body and mind to respond to what your daily experiences are,” he said.
According to the Cleveland Clinic, most wrist-worn devices track heart rate through the skin, meaning they may not be sensitive enough to accurately detect heart rate variability.