I am a blood donor, giving about 0.5L blood approx every 3-4 months. Last time I was in to give blood, I had a short chat with the nurse about Hgb levels in blood, recuperating after the donation and it got me thinking...
I was out taking a jog the next day and it was MUCH harder than a couple of weeks ago, I was short of breath almost directly after 3-4 km. Since my O2 carrying capacity had decreased by a quarter or so, it was understandable. I know it'll take a bit of time to recover the iron that was lost during donation, and I adapt my diet accordingly.
What I wonder is:
Q1: is an optimal level of iron/Hgb that is dictated by my metabolism, or can I increase my Hgb level beyond what it was earlier by adapting a more iron-rich diet?
To give an example, my Hgb levels are between 140-150 g/L normally. Having lost a quarter of that amount recently, can I go beyond that range by adapting an iron-rich diet, or will I just not take up more iron from my diet once I get back to my "normal" level?
Q2: As a follow-up question; does more iron equate higher cardio capacity? I suspect that it's not that simple...
Please note that I'm looking for information with scientifically relevant references and not urban legends or rumours that are perpetuated in gyms.