A bit of an update...
I used the power information from the pdf document, and calculated my 5 minute power output.
I burnt 136 kcal in 5 mins, which is 1896.75 Watts of power.
Assuming the same efficiency of 20%, I put out 5.66 W/Kg for 5 mins.
If this is at all accurate (highly unlikely!!!) it puts me just inside Cat 1!