Geoffrey Mutai ran the 2011 Boston Marathon faster than anyone had ever run a marathon. His time never became the world record. Boston is a point-to-point course with a net elevation loss of 138 m, and under World Athletics rules no time run on it can be a world record.
A record course can lose at most 42 m of elevation
World Athletics limits a record course's net elevation loss in Rule 31.21 of its Competition Rules: "The overall decrease in elevation between the start and finish shall not exceed 1:1000, i.e. 1m per km (0.1%)." Over a marathon, the most a record course can lose is about 42 m.
The USATF certificate for the Boston course puts the start at 141 m above sea level and the finish at 3 m. Boston's net elevation loss is more than three times the 42 m record limit.
Running downhill takes less effort at the same pace, and Boston's course is downhill overall. Chicago Marathon runners start and finish in Grant Park, so they climb back every metre they descend.
A record course's start and finish can be at most half the race distance apart
Boston runners head in roughly one direction from start to finish, so a wind from behind can push them for most of the race, as it did in 2011. Chicago runners finish where they started, so at some point they turn into the same wind they had at their backs.
Rule 31.21 also caps how far apart a record course's start and finish can be: no more than half the race distance, measured as a straight line on a map. For a marathon, half the distance is about 21 km. Boston's start and finish are 38.5 km apart.
Mutai ran 2:03:02 with a tailwind
On race day in April 2011, World Athletics reported "a strong wind from the southwest coupled with cool temperatures," and said the weather "provided a magic carpet ride" for the field. Mutai played it down. "It was at our back," he said. "But it wasn't such a big wind."
Mutai won in 2:03:02, four seconds ahead of Moses Mosop. The world record was Haile Gebrselassie's 2:03:59.
Nine days later, the B.A.A. said Mutai's time could not be ratified. Its statement named "the point to point nature of the Boston course and the fact that there is a net loss in elevation over the Boston course that exceeds IAAF limits." It added that the IAAF had set its limits on elevation loss and start-to-finish distance in 1990. The B.A.A. also said it would ask scientists whether the drop "may be mitigated by other factors that might permit the Boston course to be ratified." No time run at Boston has been ratified as a world record since.
World Athletics still uses Boston times for world rankings
Because of Boston's net elevation loss, Boston times are not valid under today's rules for world records, entry standards or legal top lists. World Athletics still uses them for world rankings, after deducting points for the steepness of the course.
Organisers of ordinary road races can lay out a course with any amount of elevation loss. World Athletics only recommends the 1 m per km limit for them. The St. George Marathon in Utah loses 792 m from start to finish, according to 42cal's course profile. No time run there can be a world record.
Kipchoge ran 1:59:40 in Vienna with banned pacing
Eliud Kipchoge ran 1:59:40 on 12 October 2019, at the INEOS 1:59 Challenge in Vienna. He ran laps of a 9.6 km loop in the Prater park. The loop was flat, and the runners ran laps of it, so the course was inside the elevation and distance limits.
Track & Field News counted 41 pacemakers, who swapped in and out in a set formation around Kipchoge. A car drove ahead and projected green laser lines on the road to mark the pace. According to Wikipedia's account, Kipchoge took his drinks from a team coordinator on a bicycle.
World Athletics Technical Rule 6 bans pacing "by persons not participating in the same race" and "by any kind of technical device." Runners may take drinks only from the start or from official stations. A record also has to come from an open race with at least three genuine competitors, and nobody in Vienna was racing Kipchoge. Runner's World South Africa reported that the run would "not count as an official world record because standard competition rules for pacing and fluids weren't followed." Nobody applied to have it ratified.
Sawe's 1:59:30 in London is the first ratified sub-two
Sabastian Sawe won the London Marathon on 26 April 2026 in 1:59:30. He pulled away from Yomif Kejelcha in the last mile, and Kejelcha finished second in 1:59:41.
London is also point to point. Khalid Khannouchi and Paula Radcliffe set world records there in 2002 and 2003, on a course inside the elevation and distance limits. World Athletics ratified Sawe's time as the world record on 23 July 2026, calling him "the first man to break two hours in a record-eligible marathon." He took 65 seconds off Kelvin Kiptum's 2:00:35, run in Chicago in October 2023.
Which famous marathon courses are record eligible?
| Course | Layout | Record eligible? | Why |
|---|---|---|---|
| Boston | Point to point | No | Loses 138 m; start and finish 38.5 km apart |
| London | Point to point | Yes | Inside the elevation and distance limits; world records in 2002, 2003 and 2026 |
| Chicago | Loop from Grant Park | Yes | Kiptum's world record in 2023 |
| Vienna 2019 (INEOS 1:59) | Laps of a park loop | Course yes, run no | Rotating pacers, a laser car, drinks from a bike and no open race |
How to check whether your PB course was downhill
A course certificate or elevation profile gives the elevation at the start and at the finish. A marathon with a net elevation loss of more than about 42 m would not be eligible for a record, whatever the hills in between. A map shows whether a point-to-point course ends more than about 21 km from where it started.
A downhill PB is still a real time. Whether it can get a runner into Boston is a separate question, covered in qualifying for Boston on a downhill marathon.
Further reading
- World Athletics Book of Rules: the Competition and Technical Rules, including the course limits in Rule 31.21 and the pacing rules in Technical Rule 6.
- World Athletics certified road events: which lists accept times from downhill and point-to-point courses.
- Boston Marathon course certificate MA21002JK: the USATF figures for Boston's elevation loss and start-to-finish distance.
- World Athletics report on Boston 2011: Mutai's 2:03:02 and the tailwind behind it.
- B.A.A. statement on Mutai's time: the race's own explanation of why the time could not be ratified.
- Track & Field News on Kipchoge in Vienna: the pacers, the laser car and the exact time.
- Runner's World South Africa on Vienna: why the run was not a world record.
- World Athletics report on London 2026: Sawe's and Kejelcha's race.
- World Athletics ratification release, July 2026: Sawe's 1:59:30 confirmed as the world record.
