HIIT, or high-intensity interval training, is having a moment — a very, very long moment. With HIIT-specific fitness studios popping up left and right (and experts constantly raving about the benefits of the afterburn), it’s easy to feel like you should be doing HIIT all the time.READ MORE:How often can your body handle this all-out type of workout, though? Probably less often than you think.story by LAUREN DEL TURCO
