A great deal in a marathon is beyond a runner’s control: cramping, upset stomach, injury, race-day illness, or just “not having it” can keep a runner in the best shape of his or her life from achieving a personal record.

If Shalane and Meb were, like amateurs, focused on PRs, Shalane might be happier about her race, given that she cut her PR by three and a half minutes, while Meb sliced his by 36 seconds. But of course they are not amateurs. Elites whose goal is to win face a different obstacle from the rest of us, namely, the performance of other elites.

Meb and Shalane ran generally similar front-running races at the Boston Marathon. One reason why Meb won and Shalane finished 7th is that Meb’s competition, including Lelisa Desisa, Dennis Kimetto, Micah Kogo, and Gebre Gebremarian, drastically underperformed (Kogo was the only one of the four to finish, in a time of 2:17:12), while on the women’s side, Rita Jeptoo, Buzu Deba, and others outdid themselves.

Shalane’s time of 2:22:02 is 13 minutes, 25 seconds slower than Meb’s winning time of 2:08:37.  Besides this year, there have been only three Boston marathons when the difference between the men’s and women’s winning times were 13:25 or less (1991, 2002, and 2005). Looking at all marathons, Meb’s time was the tenth fastest by an American male, Shalane’s was fifth fastest by an American woman. Though seventh wasn’t the place Shalane was targeting at Boston, it is a place higher than how Mo Farah finished at London.

Meb and Shalane both ran from the front, but Shalane took it to the competition from the very moment the race started. Even at the fluid stations, she quickly regained the lead after grabbing her bottle. These mini-surges didn’t help her in the end, but they were likely part of a larger psychological strategy that gave her the best chance to win – give the competition no break. Shalane tried to exert a modicum of control over the biggest uncontrollable element, the performance of her competitors, by forcing a fast race. Jeptoo admitted after the race that she didn’t feel well early on. Perhaps if she had felt just a touch worse, she would have fallen back, and the rest of the chase pack would have had to decide whether to go with the American contender or stick with the returning champion.

Meb exerted looser control over the men’s race. He was near the front of a much larger pack until he and Josphat Boit moved up between eight and nine miles in. For a short time Boit had a small lead. When Meb looked back late in the race, he may have been surprised to see that it was Wilson Chebet giving chase, not Desisa or Kimetto. While Shalane’s competitors took her as a serious threat, Meb’s competitors seemed not to worry.

Not only was Meb’s victory unforseen by his competitors, it was unforseen by the press. Like other running media outlets, we targeted Shalane as having the best chance among Americans to win. Heading in to the race, Meb’s marathon PR was only the 15th fastest among the men (Shalane’s was 16th fastest among the women), but his prior Boston PR of 2:09:26 from 2010 was faster than the times of the top three – Desisa, Kogo, and Gebremarian – at last year’s race. Kimetto and Desisa’s 2:03- and 2:04-handle races had come on flat courses. Boston is famed for its hills.

Why did we discount Meb? The competition and his age, 38, teetering on 39 (Shalane is 32). For amateurs, a newfound focus on running can lead to improvement in the late 30s, into the 40s, and beyond. Better training trumps natural physical decline. For pros, new PRs at ages closer to 40 than 30 are highly unusual because the pros generally spend much of their adult lives training hard, so improvements in training that offset natural physical decline are more difficult to achieve. Meb ran the 10,000 at the Sydney Olympics in 2000, won the silver at the Athens Olympics in 2004, and came in 4th at the London Olympics in 2012. Suddenly, we don’t see Rio 2016, assuming Meb doesn’t retire now at the top of his game, as out of the question for him.