HIIT, SIT and LISS: Why should I care about cardio?

Running track

Cardio is awkward. It's energy sapping, it's sweaty, it eats into valuable weight training time and it can make you feel completely awful, yet, it's essential to maintaining a healthy heart. So, is there any way to cut the amount of cardio you do without losing the benefits of longer sessions? According to some research, the answer is a resounding 'yes'.