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.

2 comments:

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. http://www.cyclingforums.com/t270701.html

Marco Fanelli said...

Hey Gene,

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

I'm going to post about that.