Extreme Endurance Running Might Accelerate Red Blood Cell Aging

A study in Blood Red Cells & Iron finds ultramarathon races can damage red blood cells, making them less flexible due to mechanical stress and inflammation/oxidative stress; signs of accelerated aging appear after 40‑km races and worsen after 171‑km events, though long‑term effects and duration of damage are unclear; findings could influence training, recovery, and blood storage research, but the study has a small sample size and limited sampling points.