Professional Cycling - Dutch Study: TdF Riders' Metabolic Rate Exceeded by Only Four Species on Earth....?

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Ostuni
07-16-06, 09:31 PM
Today's Sunday NYT Magazine article on Landis (http://www.nytimes.com/2006/07/16/magazine/16landis.html?_r=1&oref=slogin) (an excellent read, btw) says the TdF riders take in up to 10,000 calories per day (equivalent of 17 Big Macs), which elevates their metabolic rate that is exceeded by only four species on earth...

unfortunately, the author does not tell us WHICH FOUR????

guesses?

another tidbit: ..'in the Pyrenees and the Alps, they climb a vertical distance equal to three Mount Everests.'


Alekhine
07-16-06, 09:47 PM
One would be tempted to say the four largest creatures on earth: probably 2 or 3 species of whales (and maybe the aptly named whale shark, which is not a whale, but a fish) and elephants, but one unusual and very specific case is Iditarod sled dogs, which - during the race - consume on average of 10,000+ calories.

classic1
07-16-06, 10:10 PM
One other possibility (most likely IMO) is that the comment is total BS.

BTW - Great article. Thanks for the link Ostuni.


Ostuni
07-16-06, 10:24 PM
One would be tempted to say the four largest creatures on earth: probably 2 or 3 species of whales (and maybe the aptly named whale shark, which is not a whale, but a fish) and elephants, but one unusual and very specific case is Iditarod sled dogs, which - during the race - consume on average of 10,000+ calories.
i was thinking more of the 'rate'... hummingbird? worker ant?

Alekhine
07-16-06, 10:58 PM
i was thinking more of the 'rate'... hummingbird? worker ant?

Too small, although (in the case of the hummingbird) relative to its size, surely. In fact, a hummingbird is so small that one of its primary enemies is an insect - the praying mantiss. And there's no way a single ant could consume 10,000 cal/day. They spend half their day lugging about what amounts to a single Dorito (if that) to their lair to say they've done their part for the commune. No ant eats the equivalent of 17 big macs a day.

I was thinking rate too initially, by the way, and I'm not sure that it isn't indeed the thing to go with - it's not easy to google, hehe. I considered large mammals that were very active, but the fact is even lions tend to lie around sleeping for most of the day.

Jarery
07-16-06, 11:52 PM
It says metabolic rate only exceeded by 4 species, not caloric intake. Calories in vs body weight most likely is how they are defining metabolic rate, in which case hummingbirds and such would rate high.

If you just want to see what can take in higher than 10,000 calories a day, just go down to the local "all you can eat" buffet.

Alekhine
07-16-06, 11:57 PM
It says metabolic rate only exceeded by 4 species, not caloric intake. Calories in vs body weight most likely is how they are defining metabolic rate, in which case hummingbirds and such would rate high.

If you just want to see what can take in higher than 10,000 calories a day, just go down to the local "all you can eat" buffet.

Ahh, my bad. I'm not even going to blame this on my late night. :)

Merriwether
07-17-06, 12:38 AM
There are two natural candidates for understanding what "metabolic rate" means in that NYTimes article, which itself is referring to some unspecified Dutch study. The first is calories per day, prorated by body mass.

If that's what is meant, there is no question that the claim is wildly, wildly wrong. Obviously, if the caloric intake is prorated by body mass, even Tour de France riders are easily exceeded by vast numbers of species of small mammals and birds. To maintain their very high core body temperatures, to give just one example, small birds who winter at high latitudes must consume the equivalent of 3x their body mass *per day*. It's true that the birds tend to eat foods that are not quite as energy-dense as Big Macs, but the foods birds do eat are still energy-dense: seeds, nuts, insect eggs, grubs, etc. There is just no way that the TdF riders consume more calories per unit of body mass than these birds do. There are many more than four such species of birds, of course, and then there are migratory birds, small mammals, etc. Hummingbirds are, of course, in an entirely different class even from these animals.

Human beings are big, slow apes. Humans are so far from the prorated metabolic rates of small animals that even thinking TdF riders compare is possible only before one's first lessons in animal physiology.

We do better in understanding "metabolic rate" as just total calories per day, not prorated by body mass. Even still, there's no way that there are only four species that exceed the TdF riders on this measure. An adult killer whale is estimated to require nearly 200,000 kilocalories per day--- the thing weighs tons, let us not forget. There are surely more than three other heavy, predatory sea mammals-- dolphins, whales, large seals-- that would starve on 10,000 calories per day. That leaves aside elephants, or other active, large land mammals.

Maybe the study is referring to the length of the energy-intensive rides themselves. We need to see the study, in short.

OrionKhan
07-17-06, 12:41 AM
It seems like I remember something from watching an old national geographic/discovery type show that said some type of shrew has to consume its body weight worth of food daily or starve to death. If it wasn't a shrew, it was some other type of rodent.

cyclezealot
07-17-06, 01:04 AM
Interesting study.

Ostuni
07-17-06, 11:14 AM
...If you just want to see what can take in higher than 10,000 calories a day, just go down to the local "all you can eat" buffet.
funny because it's true....

WD_40
07-17-06, 03:24 PM
If we're talking high metoblic rates, I would say hummingbird and shrew. Some shrews eat 1.3 times their body weight in food per day.

Edit: Ah, here we go:

In fact, only four species are known to have higher rates on Saris's energy index than the professional cyclists in his study: a small Australian possum, a macaroni penguin, a large seabird called a gannet, and one species of marsupial mouse.

From: http://www.newyorker.com/fact/content/?020715fa_fact1

Keith99
07-17-06, 03:44 PM
Here is the one burried paragraph:

Saris compared the metabolic rates of professional cyclists while they were riding with those of a variety of animal species, and he created a kind of energy index—dividing daily expenditure of energy by resting metabolic rate. This figure turned out to range from one to seven. An active male rates about two on Saris's index and an average professional cyclist four and a half. Almost no species can survive with a number that is greater than five. For example, the effort made by birds foraging for food sometimes kills them, and they scored a little more than five. In fact, only four species are known to have higher rates on Saris's energy index than the professional cyclists in his study: a small Australian possum, a macaroni penguin, a large seabird called a gannet, and one species of marsupial mouse.



I'll let others comment on how this is miles different from any reasonable comparison.

JungleCat
07-17-06, 09:39 PM
Tomorrow is the "Day of Steve". I took the day off from work, first one in 5 months, to see this stage and its the only stage I will get to see this year. I'll follow it with a punishing ride in the heatwave. God I love this time of year.

Ostuni
07-18-06, 07:15 AM
...only four species are known to have higher rates on Saris's energy index than the professional cyclists in his study: a small Australian possum, a macaroni penguin, a large seabird called a gannet, and one species of marsupial mouse....
hilarious. in my mind's eye will be seeing images of macaroni penguins (whatever they look like) on road bikes when i'm watching the tour tonight...

Ostuni
07-18-06, 07:16 AM
Tomorrow is the "Day of Steve". I took the day off from work, first one in 5 months, to see this stage and its the only stage I will get to see this year. I'll follow it with a punishing ride in the heatwave. God I love this time of year.
would like to see a graph of BF members' sick days in july versus the rest of the year....