Wednesday, July 27, 2011

Doping - Clarifying My Blood Passport Misconceptions

(Thanks for the anonymous help from a doctor that also follows cycling.)

I promised to try and clear up some misconceptions from an earlier post that perused some doping thoughts, and now, a bit late, here is some more information.

To review, I thought out loud (in font) that it could be possible that I might inadvertently alter my blood profile through some innocent action. Specifically I wondered out loud if maybe eating a whole lot of Angus beef would raise my hematocrit. I'm not aware of how blood stuff reacts to whatever I do, so would my hematocrit rise suspiciously if I went on a week long binge of Angus burgers? What if I rested and recovered and suddenly had a much higher hematocrit? Maybe drinking orange juice does something, or putting a lot of wasabi on sushi.

Well, now that I've learned a bit more, I can sleep better at night. It would be really hard to inadvertently screw up my blood profile.

It seems that the biological passport makes sense. After all it's not like a bunch of bike racers got together to figure out how to catch cheats. They're doctors, scientists, and they geek out on blood like I geek out on... gluing tubular tires. Or race tactics. So these doctor types know stuff I don't even know I don't know.

They understand how blood works and how things change when a less-than-scrupulous rider tries to manipulate their blood to their advantage.

So.... what's that mean about my prior post?

Well, let's go about shredding my unscientific thoughts.

First, don't go eating a lot of iron. The highest ever hematocrit I ever saw was 49%, and that was after eating a whole boatload of Angus beef burgers for a week. However, I didn't see 49% because of the burgers. Apparently eating iron doesn't make your hematocrit jump any higher than normal. It'll get you to your normal, but if you ingest too much iron it's poisonous.

If you're anemic (lacking iron, i.e. you're depleted), then a diet rich in iron will help your iron levels get back to normal. If you regularly eat iron rich foods (like those burgers), then your iron levels are probably fine. You store excess iron in your liver, and if you have even more than your liver can hold, you get poisoned (hemochromatosis, a term I learned from a doctor).

If you're iron deficient it shows up in your blood profile. You'll have smaller red blood cells, they'll be less red, but you'll have about the same number of cells. If such a person takes iron, the red blood cells return to normal.

But if you take extra iron, you don't get super fat red blood cells, you don't jump 10% on the hematocrit scale, nothing. You return to normal and if you take more, you just have more iron in your liver.

Incidentally red blood cells last about 100-120 days. That means that about 0.8 to 1% of your blood gets "renewed" every day. With my Angus beef diet over about seven days, that means that my body replaced about 6% of my blood. Even if my new blood was 100% red blood cells, I'd have increased my hematocrit only about 6%. Since my blood is naturally about 46-48% red blood cells, there'd be no difference in my hematocrit or % of red blood cells.

It's like cholesterol. Most of the cholesterol in your body is created within. It's not diet as much as it is other factors, like exercise or whatnot. Food accounts for about 15% of your cholesterol level. Other stuff counts more.

Likewise, blood parameters are basically set by the body. Diet only fulfills the parameters; it can't force them outside those boundaries.

EPO works because it boosts your red blood cell production. Rumor has it that some racers had as high as 60%-64% hematocrit levels.

I've mentioned a term, hematocrit, so I'll explain it a bit further. It's the most elementary of blood parameters - "what percent of your blood is red blood cells?". It's easy to manipulate - you can inject fluid that doesn't have red blood cells and you immediately lower your hematocrit. Basically you just diluted your blood. Hematocrit stands out to me because it was the first test for EPO around (if your hematocrit was over 50% you were given a two week "health break"), it's gotten racers in trouble. Probably the most significant event was when Pantani tossed from the Giro the day before the finish, while in the leader's jersey.

Hematocrit is unique in that it's something that a normal physical will mention in the course of a physical. In other words it's something that us normal people can actually understand. We can find out our own hematocrit level without much trouble.

I, of course, checked out all my hematocrit readings from my physicals. I'm proud to say I hit over 49% once, although recently I'm bang on around 46%. Disappointing, as it's one of the only things I'm "good" at relative to the pros.

Or, if I put it this way... I just did a 20 min FTP test and held 221 watts for 20 minutes. That's not so impressive. A 46% hematocrit makes me grin, a 49% is worthy of a fist pump. But 221 watts FTP? Err...

Racers figured out how to beat the hematocrit test. They'd travel with a centrifuge, check their blood, and either drink lots of water or inject fluids into their blood to thin it out. Even with the 50% checks there was rampant drug use, so I (and probably more than a few others) lost faith in the system.

The blood passport seemed to yet another easily beaten system. But it's not.

You see, hematocrit can be manipulated easily, but if you manipulate it, you alter several other blood parameters. Hiding those manipulations is tough, and that's what the passport looks at.

These parameters include:
1. Reticulocyte count ("Reties" are red blood cell precursors)
2. % of reticulocytes as part of total red blood cells

And some less significant ones:
3. Red blood cell shape (volume)
4. Red blood cell color (Hb)
5. Hb concentration

Like any system that reacts to changes, if you start fiddling with stuff, the various parameters start to change. Such changes, in certain combinations, can be a strong indication of doping.

For example, if I were to infuse blood, I'd have a lower Reties count because apparently infused blood would have more mature cells. If I took EPO (which stimulates red blood cell growth), I'd have a higher Reties count as my marrow started cranking out red blood cells like there was no tomorrow. There'd be a lot of brand new red blood cells zipping around.

I could inject saline solution to dilute my blood, to keep my hematocrit low, but I'd just pee out the extra fluids. I'd have to inject the solution immediately before a test, which is hard since once you're notified you're being tested, you're not supposed to do stuff like, oh, take a shower alone or go to the bathroom alone.

This is why a racer cannot leave the sight of the dope control chaperone until the racer gets handed off to the actual dope control officer. It's also why it's so unusual if the racer is left alone for any amount of time once they know they'll be tested.

Plasma would help keep the hematocrit down longer than saline solution. There were some racers busted for using plasma expanders - that would compensate for a blood transfusion, i.e. an insertion of a lot of red blood cells. The expanders would keep the hematocrit down, but then you have to hide the expanders. Life is tough.

(I like how a doctor says he "unintentionally" ingested an intravenous thing. Also, he states confidently that the tests detected no EPO. Probably not since it seems like he was simply transfusing his own blood. A Retie count would be in order here.)

Before the blood passport testers only had a snapshot of the rider's blood profile. You couldn't really judge someone unless they had some weird baseline numbers, like a 60% hematocrit level. For other parameters you wouldn't have any idea if a particular Retie count was normal or not (for that individual).

With the passport testers could see other bits of information over the course of time. For example, someone commented on my post about my 46% hematocrit that my number is a "high normal" number for a sea level guy. One of the first blood passport cases wasn't even in cycling - it was in speed skating. The busted skater, Claudia Pechstein, had a high normal hematocrit (which isn't a problem by itself), but, more significantly, the Reties count was all over the place. The latter pointed to blood manipulation. The skater was suspended for two years and the penalty stood.

I assure you that Reties values are pretty stable, whatever it is. Unfortunately that's one of those blood values that you don't see on a regular basis, so I don't know what mine is.

Granted, there are innocent factors that affect blood parameters, but, apparently, as part of each test, the athlete gets asked questions relating to these parameters. I suppose that a doper could always say, "Yeah, I've had a fever" (or whatever else affects hematocrit) every time they get tested but that'd also throw some red flags.

So what's all this mean?

It means that list the UCI leaked (involving suspicion levels based on the blood passport) is pretty significant. Weird blood parameters are weird because they're not normal, and weirdness is bad when it comes to dope tests.

I'll have to review that list and compare them to the top finishers in the Tour. It'd be interesting to see if some of the higher or more suspicious racers in the list suddenly lost a lot of performance in the Tour. It would also be interesting to see if a racer low on the list, i.e. not very suspicious at all, suddenly does better.

Both scenarios would indicate the blood passport is helping clean up the sport.

And that makes checking race results a lot easier.

No comments: