Fitness trackers and smart watches are widely popular wearable devices that measure several types of health metrics, including step count, calories burned, sleep quality, Vo2 max and heart rate.

The Whoop rival tested.

You probably check your step count religiously, maybe glance at your heart rate during workouts, and might even pay attention to how many calories your fitness tracker claims you’ve burned. But ...

As wearable technology has grown more popular, it’s not just researchers and cardiologists who are paying attention to heart rate. You might be monitoring your own all day long via a fitness tracker ...

A few of the most important insights are heart rate variability (HRV), which describes the difference in time between the ...

A lower resting heart rate indicates an efficient heart and a higher level of parasympathetic activity. When you’re at rest, your nervous system ideally minimizes sympathetic activity, so you’re ...

Oura sold 5.5 million rings in 2025 but does the device actually make you healthier?

Cailbhe Doherty receives funding from the Health Research Board in Ireland (Grant ID: HRB ILP-PHR-2024-005) and Research Ireland (Grant IDs: 12/RC/2289_P2 and 22/NCF/FD/10949). There are no conflicts ...

Your heart beats around 100,000 times every day. Heart rate is a key marker of cardiovascular activity and an important vital sign. But your pulse is not as steady as a precision clock – nor would you ...