>I've found this to be the case w/other interval workouts as
>well--even though you feel like you're working SO hard you're
>burning fewer cals.
>
>So someone who's more educated in exercise physiology please
>'splain. What are the benefits of HIIT vs. steady state?
>I've always preferred steady state b/c it does seem to be a
>better fat burner. If I remember correctly something about
>HIIT causes your body to burn cals/fat after you finish the
>workout? Is this true? Because I'm getting ready to shelve
>all my HIIT permanently. I'm starting to think they're just
>not worth it. I don't enjoy them & they're too hard for what
>you get (or don't get) out of them.
I think one problem is confusion about what is interval training, and also about what is HIIT. Kimberly's workout isn't really interval training, IMO, but circuit training (Greg Twombly/CIA tends to confuse the two a lot, calling most of the circuit workouts "interval" workouts).
Cathe's IMAXs are interval workouts, but not HIIT. HIIT would be more like doing the blast-only portions of Cathe's Imaxes, with short recovery periods between, going all-out on the intervals, and only going 20-30 minutes, because HIIT is hard to maintain for longer than that.
One of the benefits of interval training in general are that when you do the higher-intensity segments (getting at or near your anaerobic threshhold), you burn more calories, and that boost in metabolism continues even through the recovery periods. There is also more of an 'afterburn' to these workouts, so you burn more calories in the minutes and hours after the workout is over.
ETA: when in doubt, consult Wikipedia:
http://en.wikipedia.org/wiki/High-intensity_interval_training