Work Your Entire Body With This 16-Minute HIIT Workout — PS: It's Equipment-Free

When we saw Kelsey Wells's 16-minute HIIT workout, we knew it was going to be legit. It's perfect for those days when you have no idea what to do at the gym, you want to work out at home, or you've got meetings lined up all day and need a quick, effective workout. In her caption, Kelsey said to do …