what to log HiiT as?

I split it up. Say I run for my life for 1 minute, and then walk fast (my little rest period) for 2 minutes, and I do 12 rounds. I log it as 12 min of running, fast. And 24 minutes of walking, fast. Whatever the speeds are that I ran/walked at. I think MFP calories burned are a bit off, on the high side. I am sure with a HIIT workout I am burning a pretty high rate, but not what MFP says. I always log my 8 min warm up and cool down as well. I am still moving, just at a slow pace. Does that help?