Thursday, November 02, 2006

Blood Doping in Reverse!

Today's ride proved to be a painful yet enlightening experience. You see, I donated a pint of blood three days ago, which at my weight amounts to a bit over 10% of my blood. Now the human body quickly recovers the total volume of blood (within 24-48 hours) but it takes much longer to regenerate the lost red blood cells to the pre-donation levels. Depending on the individual, it takes anywhere from 3 weeks to a couple of months. So, three days after donating, my volume is back to normal but the red-blood-cell amount is probably still down 10% or so.

How would this affect a maximal aerobic effort?

Every Thursday a group of us ride up Old San Marcos Rd. at lunchtime and frequently it's an all-out effort. This road ascends 370 meters at an average slope of about 8%. Last week I rode a time of 15:59 and according to Analytic Cycling that required an average power output of approximately 300 Watts, or about 5 W/kg in my case.

Today, with basically the same conditions and an equivalent all-out effort, my time was 18:00. That translates to approximate 260 Watts, or about a 13% drop in power!! It was a very strange sensation, like riding with extra weight or some mysterious force working against me.

I did a bit of research and discovered that precious few studies have been done on the impact of blood donation on aerobic effort. One that gets cited often is:
  • Panebianco RA, Stachenfeld N, Coplan NL, et al: Effects of blood donation on exercise performance in competitive cyclists. American Heart Journal, 1995

Apparently this study's findings are consistent with my observations today.

Now what I find particularly intriguing--and troubling--is imagining the impact working in the other direction. If a rider boosts his red-blood-cell amount by 10% does he get an equivalent increase in power output? Probably not, but even at 5% it would still have a dramatic impact on race results. In hilly category 1/2 or Masters road races, that improvement would take a 10th-to-20th-place finisher and make into him a winner. I don't see why that amount of improvement wouldn't apply at higher levels too. The temptation to cheat at the Pro level must be overwhelming.


Gene R said...

Hey Mark -
Here's an interesting thread (written by a former elite amateur)who doped to land a pro contract.

His results? Scary! He used testosterone and EPO and quickly raised his FTP (60 min power) from 350 to 420 Watts! To read more go here.

Marco Fanelli said...

Hey Gene,

Wow! That's a thought-provoking thread--thanks for pointing it out.

I'm going to post about that.