A new study finds athletes who ran ultra-long races — from 25 miles to more than 100 — showed signs of red blood cell damage that could affect how well oxygen and nutrients are delivered throughout the body.
Pushing your body to the limit may cost you more than sore muscles.
A new study suggests extreme endurance running may damage red blood cells — affecting how well they do their job.
Red blood cells are responsible for carrying oxygen, nutrients, and waste throughout the body. To do that, they have to stay flexible enough to squeeze through tiny blood vessels.
Researchers collected blood from 23 athletes before and after they ran either a 25-mile race or a 106-mile ultramarathon. They analyzed thousands of proteins, lipids, metabolites, and trace elements in both plasma and red blood cells.
The results: After both races, the athletes’ red blood cells were less flexible and showed signs of accelerated aging and breakdown, especially in those who ran the longer distance.
The researchers say the damage is likely tied to changes in blood fluid pressure, along with inflammation and oxidative stress.
Future investigations will need to examine how long the damage takes to repair, whether there are long-term effects, or if it ultimately helps or harms the body.
The lead author says, for now, they can’t advise for or against these events, only that persistent stress appears to damage the body’s most abundant cell.
Source: Blood Red Cells & Iron
Author Affiliations: University of Colorado Anschutz
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