Everything you need to know about photoplethysmography (PPG), the technology behind heart rate measurements in fitness watches and smart rings. When you purchase through links on our site, we may earn ...

A leaky heart valve occurs when a heart valve doesn’t close properly, allowing blood to flow backward. During pregnancy, this condition can affect circulation and increase strain on your heart. A ...

Rowing machines and treadmills do not challenge your cardiovascular system in the same way, so what is the science behind it? When you purchase through links on our site, we may earn an affiliate ...

As your exercise session becomes more intense and more work is done, your heart beats faster and faster. This relationship means you can use heart rate as a surrogate measure for the intensity of ...

A marathon pushes the human body close to its limits. Legs tire, lungs burn and the heart works hard for hours on end. For years, that strain has raised an uncomfortable question: does running 26 ...