Sunday, October 11, 2009

5 Degrees from Perfection at the Death Row Regatta

Typically this blog tries to dig into into questions on the boundary of theology and philosophy. Not this time. This time's just for fun as we look at my experience of rowing 25 K, 15 1/2 miles, upstream from the Port of Duluth to the mouth of the St. Louis River in a Rowpedo/human-powered canoe. I'll use a series of numbers to frame the experience.


The picture here is of a 54-year-old man and his daughter who rowed as a mixed pair. To celebrate his birthday every year Peter rows as many kilometers as he is years old. That's 33 1/2 miles, more than double the Death Row Regatta distance. One wonders how long he will be able to meet that challenge. I certainly hope to talk with Peter again next year at the race and hear about his 55th birthday celebration!

116/60 & 208-20=188

OK, so I'm no model and a loss of 20 lbs. isn't big news. But the picture here shows a 51-year-old man (me) with blood preasure at 116/60 and a resting heart rate of under 60 beats per minute to boot. Having gone from 140/70, boarderline high blood preasure, to pretty much ideal blood preasure and heart rate, I think that I can call the training that I did this summer to prepare for the race a success--at least by the really important measures. As a side note, 20 years go when I was training for some road races my blood preasure was not this good. I can't claim that this is more than a guess, but perhaps exercising in a recumbant position allows the body to pump blood at a lower preasure than is needed when the body is vertical, and perhaps exercising at a lower blood preasure somehow fascilitates a lower resting blood preasure. It's a question worth asking.

55 and 0

Ideal weather for a 25 K Regatta would be cool with no wind. That's what we had on the morning of September 13: 55 degrees and no wind.


Looking at this picture, give special attention to the oar blades. They're canted about 5 degrees forward. That slight tilt made for a very difficult row. Sweeping backward in the water, the incline caused what rowers call "oar dive." That is, the oar blades functioned like an inclined plane in the water, causing the blades to dive. Here's the impact:

a) Pushing on the pedals (with the force I trained at) overpowered my ability to keep the oars from diving: So I cut back on the effort directed to the pedals.

b) Pushing forward on the oars to propel the canoe would have meant that the oars dove even more, and would have taken away from the effort of the arms to keep the oars from diving: So I lost the effort of the arms that would have gone to propelling the canoe.

c) Because less effort went into pushing on the oars, the stroke rate went down.

d) Because oars that dive tend to get stuck in the water at the end of strokes, two unfortunate consequences occured. 1) Sometimes I dragged an oar at the end of a stroke, breaking the canoe's momentum, or 2) the oars were not timed exactly as they came out of the water, causing the canoe to wobble. And when a canoe is unstable, it is difficult to row effectively. Do you see a vicious feedback loop? I spent the first part of the race figuring out how to deal with this unwelcome challenge...

e) I therefore had to take extra care to prevent the vicious circle just described rather than enjoy the race and focus on the beautiful setting.

How did this happen? Well, I think I'll blame it on all the really terrific people I met while I was rigging my canoe! :-)

What was the total impact? Well, one horsepower is 550 foot pounds per second. My strokes--arm and leg--are about 18 ", and I was training at a little over 60 per minute most of the summer. Last figures: my leg imput went from 40-50 lbs. per stroke to around 35-40 (estimated), and I lost all of my arm input, estimated at around 12 lbs. per stroke. Using these numbers, the following horsepowers result.

Before 5 degree error: (40 X 2) + (12 X 2) X 1.5 = 156 foot lbs. per second, or .28 horsepower expected over the course of the race.

After 5 degree error: (35 X 2) + (0 X 2) X 2/3 X 1.5 = 70 foot pounds per second, .13 horsepower. (The multiplication by 2/3 was needed to account for a slowing stroke rate from about 1 per second to about 2/3 per second due to the factors noted above.)

Conclusion regarding the 5 degree error: It was a lot bigger than one would imagine! I'll pay a little more attention to my rigging next time...

2, 1, and 2:20

Even with my self-inflicted handicap, I was able to race OK. With my Wenonah Wilderness canoe I came in just ahead of a father and son team paddling a Wenonah Spirit II, to beat the only other canoe in the race. The competition was great fun, and my 3:13.40 time was the second best in the race's ten-year history--not that a lot of canoists have participated in the ragatta. Only seven, by my count. My point, here, is just that to sustain somewhere around 70 foot pounds per second of effort over more than three hours isn't too bad, even if it's about 45% of one's expectations going in...

So here's my commitment for next year: To lose 10 more pounds and get in even better shape. To race in a racing, rather than a recreational canoe (19 lbs. lighter, a 12% vs. a 16% aspect ratio, and much stiffer and narrower in the bow and stearn). And to make several improvements to Rowpedo. And finally, need I say?, to rig the oars correctly! Given good weather, I predict a 2:20 time in 2010. Brash? Yes. But my brash commitment to lose weight and get in shape paid off this year, so I'm just doing it again--and I'm doing it right away to prevent any feeling that I can afford to "let myself go."

Below is a picture of the father of the single scull winner--and one of the two paddlers that I was furtunate to meet and enjoy competing against. Typical of the kind of people I met over the weekend, I was being given terrific advice on how to improve my performance next race. How cool is that from a fellow competitor?!

Next is a picture of some of my family, who came to support me. I have seldom felt as loved as I did by this show of support! Thanks Sally, Tug, Carl, Nan, Maria, (and Willa, Frieda, and Walter)!

It was a fun year of rowing. Below, see the proper canting of the oars and the changing of the seasons here in Minnesota. Yea, that guy in the photo looks lost in thought--whether about his next rowing or biking design or something Augustine said 1,600 years ago is not known...

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