In the motorcycling world, they have various "iron butt" challenges, however with the "don't exceed the speed limit rule, most are seeminly impossible (1000mi in XX hours, etc). Accomplishment is measured by time/date stamps on gas recipts.
if if a suffer fest was to be an accomplishment do they have power meter requirements and measurements to keep it honest? 10-11 hours of honest heart rate, cadence and power output is respectable.