alt Hacker NewsIt’s well known ultra training destroys your heart.
In any sport.
They tested the blood of marathon runners and found heart attack markers in many of them because the heart muscle is being damaged and healing and scarring and hardening the muscle leaving young ultra trainers with the heart of an 80 year old.
The best modern advice is don’t overtrain.
Additionally recent studies have shown high duration/volumes of cardio increases plaque buildup in the arteries.
"Indeed, many studies have shown a relationship between endurance sports and higher volumes of coronary calcified plaque as determined by computed tomography."
https://pmc.ncbi.nlm.nih.gov/articles/PMC11395881/