With a continuously running clock do one pull-up the first minute, two pull-ups the second minute, three pull-ups the third minute... continuing as long as you are able. Use as many sets each minute as needed.
*We took this idea from Iron Major CrossFit. If you can no longer "advance" (i.e. do that minute's worth of pullups), you drop by 5 and do the rest of the workout at that number to a minum of 20 mins. Example: Cadet "X" does 8 full minutes, but can't get all 9 in the 9th minute. For Minutes 10-20 he does 4 every minute.
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