Interval training, characterized by alternating periods of more intense and less intense work, is a broad category that encompasses various high-intensity training protocols.

“So again, like, you know, first of all, it's all interval training. Whether it's HIIT depends on your definition a little bit and so that's why, again, you know, I really like this idea, this notion or this terminology of interval training because it covers all the bases. It's just alternating more intense, less intense periods of work.”