We reveal the secrets from many of leading North American contenders in Chicago including Dakotah Popehn, who ran 5:20 in the mile in college, but revealed she wants to run sub-5:20 pace for 26.2 on Sunday. Plus can Rory Linkletter get the North American record while sporting a mullet?

No woman has 3-peated in Boston this century. Will Hellen Obiri end that streak on Monday? And do the Americans Keira D'Amato, Sara Hall, Emma Bates and Dakotah Popehn have much of a chance?