I was borderline anemic several years ago, and had episodic symptoms while running (heart beating crazy fast, couldn't breathe), which stopped me from continuing a few training runs. I found out it was iron, took supplements, all was fine.
Recently I found a better supplement which increased my ferritin levels from around 35 that I could normally get it to, to up above 50 and with no side-effects. My new doctor just told me that it didn't matter, and as long as ferritin doesn't fall into anemia levels, that it being higher/lower it wouldn't affect my running times, just at worst make me tired. My hemoglobin was 129 and she said that was totally fine.
I left confused, and a bit defensive that she dismissed my concerns. And even if being tired is the only drawback...isn't that a big deal? Training 10+ hours per week makes me tired enough, I don't need to make it harder.
Oh, and she didn't ask anything about my diet, training, past symptoms, etc.
Any thoughts? She's a sports med doctor.