I didn’t know what HIIT was, so I googled it: High-Intensity Interval Training. It mentioned burpees.
I didn’t know what a burpee was (and the picture didn’t really help), so I googled it: How to do a burpee (video): it’s a combination of a squat thrust (I had to google that, too), a pushup, and a jump.
Google furthermore let me find a better graphic:
More like, how to do a burpee
The HIIT page says: Do as many burpees as possible in 20 seconds.
So, that would be zero, then? Sounds do-able. Not sure how it helps the mitochondria, though.