
Zone 2 cardio: the sustainable fat-burn pace experts favor over HIIT
Experts are embracing Zone 2 training—maintaining roughly 60-70% of your maximum heart rate (max HR is commonly estimated as 220 minus your age)—as a sustainable path to fat loss and heart health. Zone 2 workouts like brisk walking, steady cycling, swimming, or easy jogging stay oxygen-rich and promote fat as fuel longer than high-intensity efforts. While HIIT can yield faster VO2 max gains, meta-analyses show similar or variable effects on body fat when comparing HIIT and steady aerobic training. Athletes often mix intensities, commonly with an 80/20 split favoring Zone 2 most of the time, and overreliance on Zone 2 alone may limit improvements. A smartwatch or fitness tracker can help you stay in the right zone.






