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Old 12-03-2006, 02:41 PM   #2
Mike Minium
Member Mike Minium is offline
 
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Join Date: Feb 2003
Location: Oakland  CA
Posts: 860
Carrie,

I'm having problems reconciling the math in Angela's article about the power ratio.

What she writes does not seem to agree with what's in the two tables (Table 1 being Athlete A vs. Athlete B; Table 2 being Athlete C vs. Athlete D).

Here is the assumption I'm making for the calculations:

Power Ratio = Watts Generated in Rowing Effort / Rower's Body Weight

I base this on Angela writing the following: "...we can calculate each participant’s power ratio, which is the total wattage he or she generates divided by body weight (in pounds)..."


I'm Confused, Exhibit 1

So in Table 1 (Page 5)...

Athlete A produces 546 watts and weighs 209 lbs, which means his power ratio is 546/209 = 2.61.

So far, so good. Everything in the table agrees with what I'd expect to see.

Athlete B produces 546 watts and weighs 128 lbs, which means her power ratio is 546/128 = 4.27.

This is where I get confused. According to the table, Athlete B has a power ratio of 2.66. That's quite a large difference between what I'd expect and what is listed in the table.

Also, in the text supporting the table, Angela writes that Athlete B had a slower time, but in the table itself Athlete A and Athlete B both are listed with 500m times of 1:26.2.


I'm Confused, Exhibit 2

So in Table 2 (Page 5)...

Athlete C produces 303 watts and weighs 129 lbs, which means her power ratio is 303/129 = 2.35.

As in the case above, so far, so good. Everything in the table agrees with what I'd expect to see.

Athlete D produces 303 watts and weighs 141 lbs, which means her power ratio is 303/141 = 2.15.

And this is where I get confused again. In the table, Athlete D is listed with a power ratio of 2.33, instead of the 2.15 I'd expect to see based on the wattage and the athlete's body weight listed. If I multiply Athlete D's bodyweight (141) by the power ratio that's listed in the table (2.33), then the total watts that Athlete D produces would have to be 329. So I'm missing something--what is it?

Help me understand, sister.

As an aside, I should note that even with the confusion over the math, I totally get the larger point of the article and it will have a big impact on how we rate our rowers at CF Oakland. And for that I'm extremely grateful. It's just bugging me that I can't tie the little details together and reconcile the math.

Thanks,

Mike



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