Ultra-Distance Strain May Make Red Blood Cells Stiffer, Study Finds
A study of 23 elite runners in two ultras found red blood cells become less flexible and show damage after extreme distances, with longer races causing greater effects and the Lands cycle repair pathway ramping up. While these changes hint at potential risks, researchers caution there’s no proven long-term harm and note the small sample and other race variables. Interestingly, the observed blood damage resembles that seen in stored blood, which could inform transfusion medicine research.