Any minute now the cycling media is going to unleash a deluge of in depth articles analyzing the recently released bio passport data. Actually, that’s a lie. No instead, you the average cyclist will have to do your own analysis. I know, I know every time bio-passport data gets mentioned it comes with a disclaimer that only super doping experts are capable of looking at it without going blind. Fortunately, that’s not exactly true either.

So lets dive in and look at some Grand Tour data from two cyclists, MJ and BT.

MJ
Hgb 14.8 13.6 13.0
Hgb z 0.39 -1.42 -2.32
Retic 1.3 0.7 0.9

BT
Hgb 14.3 13.7 14.4 14 14.5
Hgb z -0.36 -1.19 -0.2 -0.7 -0.05
Retic 0.5 0.5 0.7 0.5 0.7

So what are we looking at. Hgb stands for Hemoglobin mass concentration. Hemoglobin is the stuff in the red blood cells that carries oxygen. For simplicity, red blood cells = hemoglobin = oxygen = performance.

Rider MJ starts the tour with Hgb 14.8 and drifts down to 13.0. Rider BT starts at 14.3 starts to drift down pops up, drifts down, and pops up again to 14.5 just higher than where he started.

Hgb z stands for Hemoglobin z score. A z score is an indicator of where you are within your normal range, also called standard deviation. Typically, you are considered to be out of your normal range if you are higher than +2 (2 standard deviations above average) or less than -2 (2 standard deviations below your average).

Rider MJ starts the tour with a Hgb z of 0.39, just above average but well within the normal range. By the end of the tour he’s at -2.32, out of his normal range on the low side.
Rider BT starts the tour at -0.36 just below average but well within the normal range. Initially, he also trends down, to -1.19, below average but within the normal range. Then he recovers to -0.05 or basically back to average by the end of the Tour.

Retic stands for reticulocytes or immature (new) red blood cells. For simplicity Retic = how fast your body is making red blood cells.

Rider MJ starts out with a Retic of 1.3 at the upper end of normal. His Retic comes to the low side before recovering to 0.9. Overall MJ came in producing a lot of red blood cells and maintained decent production.

Rider BT starts out at 0.5 at the lower limit of normal trending up a little but still low. Overall, BT had a suppressed production of red blood cells.

To summarize, MJ comes in with an above average Hgb and a ramped up red blood cell production (ed. still within normal range), maintains decent red blood cell production but his Hgb still drops low, well outside his normal range. BT on the other hand comes in with with a low Hgb and suppressed red blood cell production (ed. but still within the normal range), never really ramps up red blood cell production yet finishes with a higher Hgb than when he started.

Before we try to make an interpretation, lets consider the relationship between Hgb and Retic, and the factors that effect blood values.

Hgb level is a balance between red blood cell destruction and production. It goes up when red blood cells are being produced faster than they are destroyed. It goes down when cells are destroyed faster than they are produced.

Accelerated destruction of red blood cells can be caused by, normal wear and tear, significant physical stress, and illness.

Slowing of destruction can be caused by; rest (less normal wear and tear).

Production of red blood cells (high Retic) can be caused by; low Hgb, altitude training, rest after physical stress, and EPO.

Suppression of red blood cell production (low Retic) can be caused by; high Hgb, physical stress, and illness.

Special considerations:

Dehydration: Hgb looks higher than it really is.

Volume expansion: Hgb looks lower than it really is.

Normal Patterns:
Grand Tour: Hgb decreases despite decent Retic count although retic should trend down as well.

Altitude: A modest rise in Retic is followed by modest rise in Hgb, that should not overcome significant physical stress. Returning to lower altitude should cause a tapering off of Retic and Hgb.

Recovery from physical stress: Initially Hgb and Retic are low followed by a moderate rise in Retic and Hgb. The effect should be suppressed by significant physical stress.

Chronic stress: Low Hgb, low Retic, and poor performance.

Dehydration: Hgb is higher than expected, variable Retic, and performance is decreased.

Enhanced patterns

Epo: Look for a large rise in Retic followed by rise in Hgb, persistently elevated Retic despite high Hgb, and the effect is strong enough to overcome significant physical stress.

Sudden stop of EPO: High Hgb combined with a very low Retic. Retic should fall dramatically and precede a significant fall in Hgb.

Blood transfusion: High Hgb very low retic, maintenance of Hgb despite significant physical stress and low Retic.

Blood withdrawal: Low Hgb despite high retic without some other explanation for red cell destruction.

Masking:

Transfusion plus volume expansion: Very low Retic despite what looks like a low to normal Hgb without other cause for suppression.

EPO plus volume expansion: High retic normal HgB, and an effect that can overcome significant physical stress.

Transfussion plus EPO micro dose: High Hgb, low normal Retic, and an effect that can overcome significant physical stress.

Transfusion plus volume expansion with EPO micro dose: Low to normal Hgb, low normal retic, and an effect that can overcome significant physical stress.

Abrupt stop of EPO plus altitude: Very high Hgb, with low normal retic.

Getting back to our scenario rider MJ started the tour with high normal Hgb and a revved up Retic count. If the body continues to keep production high when Hgb is high normal it must be responding to something. Possible explanations include response to altitude, recovery from significant physical stress, EPO or some combination. The values trended down as expected with a grand tour.

BT started the the tour with low normal Hgb and a very low Retic. This situation is the opposite where something must be preventing the body from revving up production bring up Hgb. Possible explanations include chronic physical stress and illness. Or Hgb may be high but look low on testing because of volume expansion. During the stress of the grand tour however, he maintained his Hgb despite poor production (low Retic). Explanations include particularly hardy red blood cells that survive longer than expected, a tour hard enough to suppress his Retic but not hard enough to break down red cells, dehydration(Hgb looks higher than it actually is), or blood transfusions plus minus EPO.

Another explanation of course is that each rider has a unique physiology that responds differently to preparation and the grand tour itself. This argument is supported by both riders staying well within the cutoff parameters for Hgb, and retic count. OFF scores where well within the normal range as well. The only notable deviation is that rider MJ had a Hgb z score less than -2 indicating a drop well below his usual range. The drop may be entirely consistent with the stress of a grand tour which is likely to be greater than the physical stress during training.

Are the riders clean? Did they dope? Certainly there is no sanctionable evidence. But consider the scenario that rider MJ and BT are not two different riders but the same rider at two different times. Does this scenario change your interpretation of the data?

The point isn’t to answer the question of whether Lance Armstrong is clean or not. What is more important is to begin to demystify the Bio Passport. Hopefully, the type of discussion above can give the average enthusiast the tools and confidence to start looking at the data themselves. Otherwise, we’re stuck with the stories that begin and end with so and so released data, and sanctions so after the fact that no one ever wins.
Part 2 and Part 3 are now up. Part 4

(Note that I am sure that a lot of information here is not entirely correct. I welcome commentary to fill the wholes and redirect the misguided spots.)