Jennie&Tim on 6/6/2008 at 18:24
It's become a common meme that people today exercise less than they did in the eighties, and that people in Europe and America don't exercise as much as people in third world countries; turns out that isn't true. There's a very complicated type of experiment called Double-Labled Water method that measures daily energy expenditure. The quick & dirty explaination is that you lable the hydrogen and the oxygen in a dose of water, they disappear at different rates depending upon the energy used by the animal involved over several days to weeks. By taking at least two measurements you get a reasonable estimate of how many calories were burned. This gets rid of any self-reporting of exercise, or forgetting to write something down, and so forth. Plus, you can use it on all sorts of beasties, including humans.
(
http://www.unu.edu/unupress/food2/UID05E/uid05e00.htm#Contents)
Turns out that humans, whether in the developed or undeveloped countries, all use about the same amount of energy. If you test various wild mammals, their energy expenditure varies by size and temperature, if you then plot where a human-sized animal at 20 C would be, we're right there with the wild animals too.
Whatever problem we have in developed nations with fat, it isn't due to a lack of exercise; which is fascinatingly counter-intuitive.
(
http://www.nature.com/ijo/journal/vaop/ncurrent/abs/ijo200874a.html)
Anyway, very interesting.
heretic on 6/6/2008 at 19:24
We may use up about the same amount of energy, but the amount of calorie intake and given ratio of fat, sugar and processed food is vastly different across the board. Obviously excersise is only part of the equation.
As an aside: My treadmill is such a great place to hang and stack miscellaneous debris that I doubt it's intended purpose was ever really to jog in place.
D'Juhn Keep on 6/6/2008 at 21:28
Quote Posted by Jennie&Tim
Whatever problem we have in developed nations with fat, it isn't due to a lack of exercise; which is fascinatingly counter-intuitive.
Yes it is
Thief13x on 8/6/2008 at 17:01
Quote Posted by D'Juhn Keep
Yes it is
yeah, I really find it hard to believe that heart disease can kill a substantial percent of America's population annually, but we get enough exercise, I just don't buy it. Although I'm sure diet is definately an issue as well. Sadly, I should be the last one to speak:(
Moghedian on 8/6/2008 at 18:42
I think that article in the International Journal of Obesity is misleading.
So they are saying that the average person now exercises just as much as in the 80's ...Maybe that's true, but I doubt it. If it is true, then it means that people really didn't exercise much in the 80's either .
The part about how the energy expenditure of humans matches that of wild animals (provided that they are both of the same body mass and in the same environmental temperature) is also misleading. If you get a 180 pound lion, and a 180 pound human and put them in 95 degrees... well...neither of them will want to do much, and might have roughly the same energy expenditure- Not Much.
That, and how would they measure the energy expenditure of a really wild animal anyway? *banishes mental image of a experimenter trying to bribe a walrus with a bucket of fish*
They might be able to do this type of experiment with a caged wild animal, but the results won't be the same. That animal simply won't move as much as a real wild animal, due to a lack of space.
Of course, what they could be saying is that it takes a specific amount of energy to move a specific amount of mass for any kind of creature. That would make sense, but it would not imply that a lack of exercise does not cause obesity. It just says that it takes X amount of calories to move a 200 lb human/walrus/lion/whatever from one place to another.
Jennie&Tim on 8/6/2008 at 20:21
Well, I can't see the whole article without paying thirty plus dollars for it; but if I were to do the wild animal thing, I would use a group of animals like the elks near Sequim which have radio collars on. Give them a dose of the labeled water, then track and catch them at the appropriate time intervals. It's not like you have to constantly monitor them.
Maybe we didn't exercise much in the eighties either, however it's also about the energy expenditure of a citizen in the developing world too.
Heart disease is killing people at lower rates than it did 50 years ago, mostly because of better medical care; but some people will have heart disease regardless of their activity levels. We're also getting older, which is one of the biggest risk factors for heart problems.
(
http://www.prb.org/Articles/2002/USTrendsinHeartDiseaseCancerandStroke.aspx)
And if you look at the article about labelling, they are definitely measuring the actual energy used, not that it takes a specific amount of energy to move a specific amount of mass.
zombe on 8/6/2008 at 20:46
Quote Posted by Jennie&Tim
Whatever problem we have in developed nations with fat, it isn't due to a lack of exercise; which is fascinatingly counter-intuitive.
No it is not - it is the obvious disproportion of eating and exercise.
However, the method itself is interesting.
Thief13x on 8/6/2008 at 23:52
eating and exercise? or exercise and ttlg?
theBlackman on 9/6/2008 at 03:02
May be you do! :D
Fingernail on 9/6/2008 at 12:05
On average I would say I have exercised more since the 80s
But then I was only around for a year and ten months of the 80s.
