Now, I am perfectly aware of two things. One, it's a cheap 10 Euro oximeter and definitely not medical grade, so the reading might have been unreliable. And two, I googled the possible reasons for low oxygen saturation, and using Dr. Google for self diagnosis is always a bit of a gamble, but the one reason that caught my eye straight away was anemia.
Runners talk about anemia quite often, it is one reason why you might be running below your potential. And running can cause anemia due to foot strike hemolysis, though that is quite rare. I do have a history of anemia, however, I used to be on iron tablets for years when I was young and I have long lost count of the number of times our GP took a blood sample to test me. That was a long time ago, however, so it may well be just a false alarm, especially with the uncertainty of the diagnosis.
Still, I went into the pharmacy on Saturday and bought some liquid iron supplement, the one that Niamh used to take when she was pregnant with the twins and which seemed to help me as well.
Actually, I have been feeling much better this week, though I can only assume that this is either coincidence or placebo because even if I really were anemic, I don't think the supplement would work quite so quickly. I'll keep taking it, though. I'm pretty sure my iron levels are not high, so taking a supplement is unlikely to cause any harm, in the worst case it may have caused slight harm to my bank balance, that's all.
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I followed the same pattern as recent weeks in training, with a long cycle on Tuesday evening and a mountain run on Sunday, though I didn't manage to run on Friday because work had been absolutely manic, I didn't manage to nip out at lunchtime and was too exhausted to even think of running after work, so I let it go.
I only managed about 50 miles of running last week, which isn't a lot when you're training for a race of the same length, though it was offset by over 100 miles of cycling, and part of the run was on mountain trails, which significantly increased the time on feet compared to what the same miles would have given me on the road.
Still, I won't be in top shape come race day. But I'll manage.