So on Friday I went to the vampires at the Red Cross and donated a pint of blood. It's a good thing to do, you know, altruism and helping your fellow man and such, but "mainly I do it for the snacks."
And also I like joking about how they instruct me to double up on my drinking.
The average person has, I think, about six pints of blood pumping around in the body, so losing a pint has notable effects right after it's over. If you stand up too fast, you might "swoon" and get dizzy and light headed for longer than you'd expect. Luckily, I have donated blood a number of times (because like I said, I like getting the snacks) so I don't normally experience this any more.
So my body probably went right to work replacing the lost blood, but it must take a while, because the Red Cross will only accept my donations once every 8 weeks. So I supposed there would be some sort of effect on my bicycling the day after. And since I am keeping painstaking track of my bicycle riding this year, on account of my resolution to ride my bike for more time than I spend commuting to and from work in my car, I think I am able to say with some degree of confidence that the loss of one pint of blood had a negative effect on my bicycling ability.
I woke up Saturday morning with a plan to ride for about an hour, since the family had plans to drive to the National Park and do some hiking for the rest of the day. I ended up going on a similar route from my house to the bike path behind the dump to the neighborhood behind the church and back home, close to 17 miles.
My average speed for this trip was 16.6 miles per hour. On other rides of similar distance and routes, my average speeds were in the 17.0 and 17.2 average (about three percent slower). Not that I'm bragging, it's just that this general route isn't very hilly so it's not too rough.
Anyway, this day after donating a pint of blood, I found myself breathing extra heavy, extra early in my ride. About 1 mile and a half into the route, there's a gentle incline that's normally no trouble. But on this day, I was sucking wind and I could feel my heart beating extra hard and extra fast. As I was huffing and puffing, I was also happy to be experiencing this interesting feeling of weak feebleness. In my mind, I knew I shouldn't have been feeling so tired and worn out so early in a ride, and that this experinece was probably due to my body running on about 5/6 of the normal load of red blood cells.
So my perceived effort to maintain any speed was quite high as I continued on my ride. And 64 minutes later I got back home and went on with the day.
Too bad I didn't go on a bike ride on Friday afternoon, right after I donated that pint of blood. I wonder how I would have done. Maybe next time...
Interestingly, I also went for a long ride yesterday afternoon, which would be two days after donating the blood. I mowed the lawn (which took an hour walking behind the self-propelled mower) and then rode for about two and a quarter hours, and that ride was more than 36 miles and the average speed was 17.3. So I tentatively am concluding that losing a pint of blood has a short term negative effect on exercise ability for about a day. Although, looking back at my previous recent rides of around 36 miles, my average speeds have been 16.6,17.7, and 18.0 average speeds, and under various weather and road conditions.
And finally, on the Resolution Front, you can see from my graphic here that I am just about 23 and a half hours behind on my goal. I think I gained about two hours over the weekend, keeping pace on my plan and I hope to end the month with a deficit of around 20 hours. November and December will see fewer commuting days, so that and the anticipated more bike riding as a result ought to keep me on track to achieve my goal.
AVERAGE PERSON HAS ABOUT 11 PINTS OF BLOOD CIRCULATING AT ANY GIVEN MOMENT. AVERAGE RBC LIFESPAN IS ABOUT 4 MONTHS. IT IS AWESOME YOU GIVE BLOOD. KEEP DOING IT!
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