HIIT for 15 minutes. I beat my previous record by about a furlong. Towards the end, as I was getting extremely tired, I had to imagine Heston in front of me stealing my bike, so I was trying to catch him (also, I was listening to the Punch-Out remix). When I finished, I immediately collapsed onto the grass and couldn't move for 3 minutes. It was awesome.

Oh, and in case you don't get the Punch-Out reference:

http://niggastolemybike.ytmnd.com/