Blood test results

after blood test , my hemocrit level is low at .39 in previous tests its been. 44 and above. since January I have not eaten any meat or chicken, I wouldn’t say I’m vegan as I still have dairy milk and cheese.

my b12 is OK

I have started to supplement my iron this week after test showed low iron as well.

I have slowed down riding this last month as I’ve been feeling tired

would increasing my riding again help me produce more red blood cells and help raise my hemocrit ?

any recommendation for best iron supplimemt im using one with vit c and zinc to help absortion and I take it with my main meal in the evening.

I’m obviously seeing a doctor but was wondering if anyone else had anything similar.


I’m no expert but I can share my personal experience and stuff I found searching around.
Not even close to controlled data: I saw a ~5% increase in hematocrit levels on my annual work health screening blood test from a year when I was casually cycling to last year when I had been doing TR plans in preparation for distance races. No telling whether there was a correlation though, as it’s only once a year and there’s plenty of other factors involved. Also not sure what the margin of error is on the test itself.
But, the info I can find from some searching around suggests that while exercise will increase your total red blood cell count, plasma volume will increase more, causing your HCT reading to go down. I’m sure there are people on this forum far more qualified than I to talk about this, but here’s the little bit I found:

What Runners Need to Know About Their Blood Test Results | Runner's World.

Regular exercise causes an increase in the number of RBCs in the blood. As an adaptation to training, there’s also an increase in plasma volume in the resting state. This volume expansion causes the hematocrit (the percentage of RBCs in blood) and hemoglobin levels to be lower than in non-athletes. The expansion in plasma volume will be reflected as lower hematocrit and hemoglobin levels on a complete blood count

Trained athletes, particularly in endurance sports, have a decreased hematocrit, which is sometimes called “sports anemia.” This is not anemia in a clinical sense, because athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation relative to sedentary individuals. The slight decrease in hematocrit by training is brought about by an increased plasma volume (PV).

I have naturally low hemoglobin (~125 g/L), never supplemented with iron and felt fine. I only started supplementing* when I started donating blood and only because they require a minimum hemo level. I’ve increased it to ~155 g/L (~25%) with inconsistent supplementation. I don’t perceive there to be any change in performance etc.

*3x 35mg/day derived from 300mg ferrous gluconate (be aware of the different types/doses of iron).

My hemoglobin has dropped also from 156 to 138. Will get doctor to proscribed my iron supplement like you say its a mine field. Just got some over counter for this week, doctor appointment is Monday so will see what his views are.

Hi Pete,
Would discuss the rest of the labs with your doctor before you go down the oral iron route. There are many, many causes of anemia, and many different causes of iron deficiency. Knowing the cause is important because you don’t want to just put a bandaid on something more serious. Before taking oral iron you probably ought to ask your doctor to tell you why you are anemic to make sure you are doing the right thing. Further, oral iron totally sucks in terms of side effects, so you really don’t want to take it unless you have no other option.
Best of luck.


This should definitely be a conversation with your doctor, preferentially a Sports Med doc or at least one familiar with how the demands of an endurance athlete will be different from an average patient they might be expecting.

Trent Stellingwerff and Peter Peeling have a recent paper out on iron considerations in an athletic population. Full paper available here

Trent has some more digestible and actionable information out there. Very worth searching around. One quick video with practical supplementation advice here. The iron doses mentioned are specifically for altitude, but the general timing advice probably applies to sea level.