In zone 1, you’re warming up for a run, and in zone 5, you’re at an all-out sprint. Recently, zone 2 has gained MVP status among the five zones, thanks in part to longevity gurus like Peter ...

"Zone 2 training refers to a certain type of heart rate training which sits between 65 to 75% of your maximum heart rate," says Tana. "Zone 2 is generally known as 'aerobic base training' which ...