ferritin wrote:
My daughter had ferritin of 13 ...started Iron supplements and ferritin went up to 45. It made a difference, she stopped getting weak "leg burn" in just regular pace runs.
TLDR: I've dealt with something similar. I hope your daughter gets back to feeling better soon.
I'm not a high school female, but a middle aged male. I recent had a very hard training cycle, then for no apparent reason started having the weird "leg burn" feeling you're talking about even during easy runs, that I've never had in 25 years of running. Then my race performance started declining. I could complete easy runs okay and I remained able to complete workouts, despite feeling bad.
Not until I went all out in a half marathon did I know something was wrong. My legs just could not hit paces I had been able to hit a few weeks earlier, while my heart and lungs weren't even feeling strained. My legs didn't even have the energy to go out too hard and bonk. Someone suggest I checked my ferritin and to my shock it was very low, at 26. Ferritin needs to be 60-100 for a male long distance runner, I'm told.
I'm not losing blood (Hemoglobin and serum iron = normal.) But I'll go months without eating red meat as the cook in my house (my wife) doesn't eat it and instead there's a lot of veggies, white meat chicken and fish on the table. Also, as a marathoner I burn through more iron than the normies and lose more running in the summer heat in the humid south.
2 weeks later, after iron supplements and eating more red meat, things are just staring to feel better. I'm told it could take weeks to months to feel 100% back to normal. I hope it happens soon, because I'm starting the hardest marathon block of my life this week, for a race in March.