Sifan Hassan and Fiona O'Keeffe Withdraw from 2026 New York Marathon

The 2026 New York Marathon lost two of its most anticipated competitors before the starting gun fired. Sifan Hassan, the Dutch-born Ethiopian runner who already has Olympic and world medals around her neck, and Fiona O'Keeffe, one of the brightest prospects in American marathon running, confirmed they will not be at the starting line in Staten Island on November 1st. Hassan withdrew due to an illness that disrupted her training during crucial weeks, and O'Keeffe was ruled out after undergoing surgery for a hamstring tendon tear. For any runner who has felt that fear of "I got sick right before the race" or "I got injured two weeks before the marathon," this news hits differently: even the best athletes on the planet are not immune to the cruel timing of an injury or infection.

The context

The New York Marathon is one of the six World Marathon Majors, alongside Boston, Chicago, Berlin, London, and Tokyo. It is not just a race: it is a spectacle that brings together more than 50,000 recreational runners with the world's elite, where the prestige of winning carries almost as much weight as the prize money. Sifan Hassan arrived as one of the main attractions: she comes off a historic 2024 and 2025, including her Olympic medal in the marathon in Paris, and her presence fueled the narrative of a possible historic run through the Majors circuit. Fiona O'Keeffe, for her part, is one of the fastest female runners in the United States at the distance, with a meteoric marathon debut that positioned her as a reference point for the new generation of American distance runners.

That both withdrew simultaneously—for completely different reasons: an acute illness and an injury requiring surgery—is not a whimsical coincidence of the calendar. It is a demonstration of something every coach knows and repeats tirelessly: the human body, no matter how elite, has a limited tolerance margin, and that margin narrows dangerously in the final weeks before a marathon, when accumulated volume and intensity are at their peak.

What the science says

The fatigue that accumulates in the final training block before a marathon is neither linear nor felt the same each day. The literature on fatigue development in endurance exercise shows that perceived effort and physiological response change as demanding sessions accumulate, and that the immune system and connective tissue are among the first to show signs of overload, even before performance itself is affected (Azevedo et al., 2021). This explains why a respiratory illness or a torn tendon often appears precisely in the weeks of highest load: the body is operating with reduced reserves.

Furthermore, there are real physiological differences between how men and women respond to training and endurance racing, including hormonal aspects, body composition, and recovery, which influence tolerance to high loads and injury risk (Besson et al., 2022). This does not mean women are "more fragile"—neither Hassan nor O'Keeffe are, they are among the most resilient athletes on the planet—but rather that understanding these differences is key to designing training and injury prevention programs that are truly personalized, something that is increasingly gaining ground in elite sport (Sutehall & Pitsiladis, 2025).

What it means for you

If you are in your final training block before a marathon, this news is a useful reminder, not a cause for panic. First: listen to early warning signs. Pain in the hamstring that doesn't go away with warm-up, or a sore throat that starts after a hard session, are not minor details in the final weeks: this is the time to reduce load, not to "push through because we're almost there." Second: strength and injury prevention work remain your best insurance. Strengthening the hamstrings and posterior chain with strength work not only improves running economy, but protects exactly the structures that suffer most in poorly managed tapering (Zanini et al., 2025). And third: take care of your immune system in the weeks leading up to the race—sleep well, don't experiment with new nutrition, and reduce unnecessary extra stress. Hassan and O'Keeffe couldn't have done more than they did; you can learn from their bad luck and protect your own preparation.

References

• "Fatigue development and perceived response during self-paced endurance exercise: state-of-the-art review." — Azevedo RA, Silva-Cavalcante MD, Lima-Silva AE, Eur J Appl Physiol 2021. https://pubmed.ncbi.nlm.nih.gov/33389141/
• "Sex Differences in Endurance Running." — Besson T, Macchi R, Rossi J, Sports Med 2022. https://pubmed.ncbi.nlm.nih.gov/35122632/
• "Personalized Nutrition for the Enhancement of Elite Athletic Performance." — Sutehall S, Pitsiladis Y, Scand J Med Sci Sports 2025. https://pubmed.ncbi.nlm.nih.gov/40164953/
• "Strength Training Improves Running Economy Durability and Fatigued High-Intensity Performance in Well-Trained Male Runners: A Randomized Control Trial." — Zanini M, Folland JP, Wu H, Med Sci Sports Exerc 2025. https://pubmed.ncbi.nlm.nih.gov/40016936/