
78,912 Boston finishers: with even pacing the βwallβ happens in 0.2% of cases
The largest analysis of marathon splits sorted runners into four pacing types. Among those who ran evenly, a collapse in pace in the second half occurred in 0.2% of cases. Among those who ran erratically β in 85.4%. The gap in finish time between the extreme groups is almost an hour.


















































