Published: 05:35 BST, 14 August 2026 | Updated: 12:47 BST, 14 August 2026
A simple heart health measurement could be one of the first indicators something sinister is going on with your health.
A person's resting heart rate is a lot more important than people may think, while it may just be a number on a fitness tracker, it can indicate all kinds of stress.
Resting heart rate refers to the number of times your heart beats per minute while your body is at rest – when you're sitting or lying down. The rhythm is set by the nervous system and keeps the body balanced.
A normal resting heart rate is between 60 and 100 beats per minute (bpm), though athletes, fit young adults and people taking beta-blockers often have slower rates. A lower resting heart rate is generally linked to better cardiovascular fitness.
Resting heart rate is most useful when measured the same way each day. Tracking it over time can reveal when something is off, especially if your heart rate stays higher or lower than usual for an extended period.
Michael Snyder, a Stanford geneticist, noticed his heart rate was elevated during an eight-hour flight to Norway – and it stayed high days after he landed. Because he tracked his resting heart rate daily with a smartwatch, he knew something was off.
Concerned, he saw a doctor and raised the red flag. After undergoing blood tests, it was discovered he had Lyme disease. Leaving the tick-borne illness untreated can lead to serious, life-long health complications.
However, because Snyder monitored his resting heart rate, he was able to catch and treat his disease early.
Monitoring your resting heart rate overtime can help indicate if something is off
Snyder's case was in a 2017 study published in the journal PLOS Biology, which found that early model fitness trackers and smartwatches could monitor the body closely enough to spot meaningful health changes before a doctor could.
The study involved 43 participants who wore sensors tracking heart rate, blood oxygen, activity and temperature for up to 11 months. Snyder was the main participant and was monitored for about two years.
The sensors collected over 250,000 measurements from all participants, and researchers found the devices can detect changes linked to heart rate, illness, inflammation, and even insulin resistance.
After analyzing the data, including Snyder’s diagnosis, researchers concluded that the sensors can do much more than count steps – it can show how the body normally functions, how it fluctuates throughout the day and when something starts to change.
One high heart-rate reading alone isn’t a reason to race to the doctor. Resting heart rate can fluctuate for everyday reasons.
