Runners in the Boston Marathon had high temperatures to deal with.
But they also got a strong tailwind that could help, too. The 13 mph wind gave runners a push at the starting line Monday. Gusts were expected of up to 30 mph.
A strong tailwind and cooler temperatures in 2011 helped Geoffrey Mutai finish in 2 hours, 3 minutes, 2 seconds. That was the fastest marathon in history at the time, though not a world record because the Boston course does not qualify for world records.
The world record is 2:02:57, set by Kenyan runner Dennis Kimetto in Berlin in 2014.