The cut-off time for the 100-mile race is 60 hours overall, or an average of 12 hours per loop, and the cut-off for the 60-mile version of the race is 40 hours overall, which averages out to approximately 13 hours and 20 minutes per loop. Once a competitor has started a loop they are not allowed to receive any assistance, other than from fellow runners, until they have finished that loop. Out of more than 1,000 starts, the 100-mile race has been completed within the official 60-hour cut-off 18 times by 15 runners. However, in 2006, nobody finished even the 60-mile "fun run" in under 40 hours. The best women's achievement is Sue Johnston's in 2001. More than 30 competitors failed to reach the first book (two miles).