Carley is a writer, editor and social media professional. Before starting at Forbes Health, she wrote for Sleepopolis and interned at PBS and Nickelodeon. She's a certified sleep science coach and ...

To get the most out of a cardio workout, you need to get your heart rate into your target heart rate zone. However you keep ... subtract your age from 220. So, take a 35-year-old, for example.