Is it HIIT

[aus_runner83]

If I don't feel like dropping dead after I finish my workout and can keep for 40-45 mins?

I work pretty hard during my intervals, it gets my HR into the 180's just recently maxed out to 190 (though the gym bike was reading 193, 194). I'm really out of breath after each intervals, and the hard workouts last 40-45 mins (on bike or ellipitcal) after that I spend the next 15-20 mins getting my HR back down to the 130's.
I'm 27, I'd say I was getting very fit running (I do it to compete) before I got injured and had to start x-training on a bike and elliptical. Only time I feel wrecked is after PT late Thurs afternoon (by then I've worked hard all week)

(btw attached e.g. of recent w/o)

 

[Goldfish]

Well, 90-100% MHR is unquestionably high intensity, and if you were doing that for intervals, then there's no doubt that you were doing high intensity intervals. But just as Mentzer's "High Intensity Training" doesn't actually require a measured percentage of max to define what is "high intensity," I don't think HIIT is actually about how high you get your heart rate. You can actually train at near maximal heart rate without it being HIIT. Of course, it'll burn calories faster than gasoline, regardless of whether it's technically HIIT or not, so I wouldn't fret too much about it. But, my understanding is that HIIT is about going as hard and fast as possible for X amount of time, then going very light for Y amount of time, and repeating. This may get you into your MHR zone, or it may not. The workload will effectively be anaerobic (and it's the lactic accumulation that makes you want to throw up at the end of it, so if you've got a high lactic threshold, then you can definitely debunk the myth that "if you don't feel like throwing up, you didn't do HIIT"). But what makes it HIIT is not what a heart rate monitor or EMG says, it's much more a matter of perceived difficulty (at least to my understanding).

As I said, don't fret one way or another. You're doing an intense cardiovascular workout, and it will plough through your energy supplies like no-one's business.