Dangers of high heart rate running?

Hi Docs, a couple years ago I wanted to reduce my waist size and improve health by getting into running. So far I’ve had a blast and have managed to do two marathons.

Both marathons I have averaged about a 185 bpm. After my last marathon, someone on Strava commented that I really need to work to reduce my marathon heart rate and that I could be setting myself up for myocardial fibrosis or ventricular strains.

Is this really something I should be concerned by? I always assumed that running for long periods of time at high heart rate would just make my heart stronger than the average person, which should result in improved health outcomes.

Maladaptive cardiac changes are not a concern with exercise in most individuals. We discuss this in detail here: