Crunching the NYC Marathon numbers: Toughest miles, boroughs and bridges

The "wall of sound" along First Avenue helps give marathoners a statistical boost. AP Photo/Kathy Kmonicek

The New York City Marathon is Sunday. The folks at Strava, a GPS tracking service for runners and cyclists, collected data from more than 44,000 runners on the New York City Marathon course between 2009 and 2013.

Here are some of the helpful and insightful tidbits of information they shared with us, in the form of a Q&A (for the full breakdown, check out this pdf):

Do nerves at the beginning of a race have an impact on early speed?

Prerace jitters are a real thing, and they impact the race: Athletes had a median max heart rate of 172 (compared with the race average of 165) in the first mile, the highest of the entire race.

Why is the first mile on the Verrazano Bridge the slowest?

The sluggish first mile pace of 8:49 min/mile is likely due to dodging other race participants and jockeying for position.

After a slow start, when does a runner start to make up ground?

Athletes try to make up for lost time from mile 1 during mile 2 with a sub-8-minute mile pace (7:56 min/mile).

There are no spectators on the Queensboro Bridge, and it’s silent aside from the pattering of feet and heavy breathing. How difficult is it?

The Queensboro Bridge around Mile 16 is tough! Runners slow to an average pace of 10:08 while crossing it.

After that silence, thousands of fans cheer along First Avenue. Does a confidence boost exist from feeding off the crowd?

The "wall of sound" along First Avenue in Manhattan inspires many runners (miles 17 and 18) -- they’re also the last sub-9-minute mile splits of the race.

But how long does that runner’s high last before reality sets in?

The added boost from First Avenue doesn’t last much longer, as runners appear to “hit the wall” at mile 19 when the average pace rises above 9 min/mile.

Do runners at least finish strong?

Runners go for the photo finish in the last one to two miles of the race: The pace picks up significantly, and the median max heart rate increases to 169 (the second highest of the race; race average is 165).

Do most runners tend to negative split the race and run the second portion faster?

No, the first half of the marathon sees an average pace of about 8:24 min/mile, the back half is slower at 9:14 min/mile.

What are the fastest and slowest bridges?

The fastest bridge crossing by pace is the Verrazano-Narrows Bridge (8:13 min/mile). The slowest bridge crossing by pace is the Queensboro Bridge (10:08 min/mile).

What about boroughs?

The fastest borough for runners is Brooklyn (8:14 min/mile). The slowest borough for runners is The Bronx (9:32 min/mile).