HIIT: friend or fad?

A couple of times a year I’ll add HIIT (high-intensity interval training) to my exercise regimen. I admit it, I succumb to the fantasy of the supernormal improvements promised by HIIT. After a couple of weeks I’ll quit and go back to running the way I do the rest of the year. For me it is therefore effectively a way to shake my body out of what could otherwise become too much of a routine (if such a thing exists).

Online, people are always raving about how amazing HIIT is. The problem is that the people who are raving about it have only done it for a week or two - like I do, too (except for the raving - I still don’t know how I feel about it). The problem is that I have yet to hear about a person who’s done HIIT on a regular basis over a longer period of time. So I am none the wiser if it’s better or if it’s just different.

Have you tried HIIT? What’s your experience? Does it have its place in the short run? Does it work in the long run?

In short: Is HIIT a friend or a fad?