5 ms·

Except your food expenditures are a sunk cost, and you can't replace them with fuel expenditures. This is literally comparing apples and gasoline.

adt2bt 10y ago
Not exactly. If you were on a maintenance diet and started biking to work, but didn't replace those calories, you'd eventually waste away. Your body's signals for how hungry you are will not exactly, but still fairly closely, match the calories you burn picking up your new biking habit.
thaumasiotes 10y ago
Your food expenditures vary with the amount of work you do, no different than your car's fuel expenditures. They are most certainly not a sunk cost for this purpose.
- incongruity 10y ago
  But the argument could be made that the average American runs a calorie surplus so some percentage of the food/fuel cost could be deducted, for Americans, at least, no?
  - thaumasiotes 10y ago
    No, not unless you take full control of their diet (they'd probably object to that). People respond to extra work by eating more. > But the argument could be made that the average American runs a calorie surplus It really can't; running a calorie surplus would result in constant weight gain. What you actually see is extreme weight stability.
    - incongruity 10y ago
      I guess the issue is surplus relative to what - recommended daily calorie intake vs. the calories required to maintain excess weight. My point was the former, yours seems to be the latter.
      - thaumasiotes 10y ago
        Well, I started off by saying "no, food expenditures are not a sunk cost, they are directly related to the amount of work you do". The idea here is that doing x extra work leads to eating x' extra food, where x' is some constant multiple of x (and "food" is measured in energy). Your response, as far as I can see, says that because Americans already run a caloric surplus, x extra work should only lead to x' - k extra food intake, where the missing k energy is made up by the existing caloric surplus. I responded then and respond again now that this perspective makes no sense; the extra work is an ongoing expenditure and must be exactly balanced by an ongoing intake. For the supposed caloric surplus to be offset against the extra work of extra walking, the person would need to be experiencing constant weight gain beforehand. Nobody[1] is. You may think that Americans weigh too much, but that's irrelevant; a change in weight is a nearly-pure one-time effect with no influence on dietary requirements. They are eating exactly the amount they already use for the activities they already do. Am I missing something about your point? [1] Actually, people with Prader-Willi syndrome will eat if it is possible to eat, no matter how full they are. They will experience constant weight gain if not subject to external control. But they have a serious genetic defect.
- sfifs 10y ago
  Actually not so much surprisingly - the key exceptions being if you are working in very cold climates where the body has to generate more heat to keep you alive or you're training competitively for very physically sports. It turns out that about 70-80℅ of what most people consume goes into simply keeping them alive (research basal metabolic rate & daily calorific requirement) and the impact of "work you do" is only a small variation - with the above exceptions. Also interestingly (unable to search the paper reference on phone) there is research that shows that dramatically different lifestyles like Namib desert nomadic hunter-gatherer vs. typical urban don't actually differ on metabolic rates (accounting for non-fat weight)
  - allendoerfer 10y ago
    You should have posted that at the top level, so this could be the top comment. While the statistics are nice to look at, I have read the article you mentioned, too (was on HN a while ago) and instantly thought that metabolism unfortunately renders the whole calculation useless and wrong.
    - thaumasiotes 10y ago
      > While the statistics are nice to look at, I have read the article you mentioned, too (was on HN a while ago) and instantly thought that metabolism unfortunately renders the whole calculation useless and wrong. Why did you think this? Can you articulate a change that metabolism would make to the calculation?
      - allendoerfer 10y ago
        It adapts, like my parent comment has said. Most of our energy is spend on keeping the system running, not running with our feet. If we start to run, we burn more energy, because our metabolism has not adapted yet, once it adapts (see his example with Africa), there is very little change. Obviously this is simplified.
        thaumasiotes 10y ago
- sfifs 10y ago
  Actually not so much surprisingly - the key exceptions being if you are working in very cold climates where the body has to generate more heat to keep you alive or you're training competitively for very physically sports. It turns out that about 70-80℅ of what most people consume goes into simply keeping them alive (research basal metabolic rate & daily calorific requirement) and the impact of "work you do" is only a small variation - with the above exceptions. Also interestingly (unable to search the paper reference on phone) there is research that shows that dramatically different lifestyles like Namib desert nomadic hunter-gatherer vs. typical urban don't actually differ on metabolic rates (accounting for non-fat weight)
TulliusCicero 10y ago
Also, driving your car increases maintenance costs on the vehicle, whereas walking decreases maintenance costs on the 'vehicle' (healthcare).
dogma1138 10y ago
Not really, I don't like cycling in the city (not secure enough about not being plastered by a truck, especially considering how little fuck UK drivers seem to give) so I walk to work for almost 2 years now. I started because I wanted to lose like 8-10lbs during a time when I couldn't exercise regularly at the gym which were lost within about 6 weeks. I walk fast at about 6KM(my gait isn't very long because I wear either jeans or dress pants and I am of average height, but still I'm doing 130-135 steps per minute) an hour according to Google Fit/Apple Health, and I walk between 11-15KM a day (~2-2.5 hours I take a longer route through Hyde Park if the weather is nice and I'm not in a rush getting to or from work). This daily walk alone increased my daily rough caloric requirement to about 2800-3000 calories, that's 600-800 (k)calories over my daily default if i don't do any physical activity other than getting up and commuting to work on the tube. If i don't increase my caloric intake i would lose between 0.5 and 1 KG a week so in this case and in every other case the "food expenditure" isn't a sunk cost, now you might say that my caloric intake doesn't have much impact on the grand scheme and you would be correct, if I need to eat another slice of pizza or another muffin it doesn't affect anything in the long run, if anything it probably means we might "waste" a bit less food. But given the current cost of each food calorie that you intake if everyone all of a sudden goes up to 3000 Kcal daily requirement it will have an effect on the environment and the economy. What you should take from it is not that walking is bad for the environment but is that the global food production is highly inefficient ATM, food is cheap especially in the US but it comes at a pretty big price also.
collyw 10y ago
Yes, it is taking the total calories used (actually its not that clear). It should be comparing the extra calories burned by cycling minus the calories burned sitting. Driving the car, you will still be burning most of those calories as well as burning the gasoline.

adt2bt 10y ago

Not exactly. If you were on a maintenance diet and started biking to work, but didn't replace those calories, you'd eventually waste away. Your body's signals for how hungry you are will not exactly, but still fairly closely, match the calories you burn picking up your new biking habit.

thaumasiotes 10y ago

Your food expenditures vary with the amount of work you do, no different than your car's fuel expenditures. They are most certainly not a sunk cost for this purpose.

incongruity 10y ago
But the argument could be made that the average American runs a calorie surplus so some percentage of the food/fuel cost could be deducted, for Americans, at least, no?
- thaumasiotes 10y ago
  No, not unless you take full control of their diet (they'd probably object to that). People respond to extra work by eating more. > But the argument could be made that the average American runs a calorie surplus It really can't; running a calorie surplus would result in constant weight gain. What you actually see is extreme weight stability.
  - incongruity 10y ago
    I guess the issue is surplus relative to what - recommended daily calorie intake vs. the calories required to maintain excess weight. My point was the former, yours seems to be the latter.
    - thaumasiotes 10y ago
      Well, I started off by saying "no, food expenditures are not a sunk cost, they are directly related to the amount of work you do". The idea here is that doing x extra work leads to eating x' extra food, where x' is some constant multiple of x (and "food" is measured in energy). Your response, as far as I can see, says that because Americans already run a caloric surplus, x extra work should only lead to x' - k extra food intake, where the missing k energy is made up by the existing caloric surplus. I responded then and respond again now that this perspective makes no sense; the extra work is an ongoing expenditure and must be exactly balanced by an ongoing intake. For the supposed caloric surplus to be offset against the extra work of extra walking, the person would need to be experiencing constant weight gain beforehand. Nobody[1] is. You may think that Americans weigh too much, but that's irrelevant; a change in weight is a nearly-pure one-time effect with no influence on dietary requirements. They are eating exactly the amount they already use for the activities they already do. Am I missing something about your point? [1] Actually, people with Prader-Willi syndrome will eat if it is possible to eat, no matter how full they are. They will experience constant weight gain if not subject to external control. But they have a serious genetic defect.
sfifs 10y ago
Actually not so much surprisingly - the key exceptions being if you are working in very cold climates where the body has to generate more heat to keep you alive or you're training competitively for very physically sports. It turns out that about 70-80℅ of what most people consume goes into simply keeping them alive (research basal metabolic rate & daily calorific requirement) and the impact of "work you do" is only a small variation - with the above exceptions. Also interestingly (unable to search the paper reference on phone) there is research that shows that dramatically different lifestyles like Namib desert nomadic hunter-gatherer vs. typical urban don't actually differ on metabolic rates (accounting for non-fat weight)
- allendoerfer 10y ago
  You should have posted that at the top level, so this could be the top comment. While the statistics are nice to look at, I have read the article you mentioned, too (was on HN a while ago) and instantly thought that metabolism unfortunately renders the whole calculation useless and wrong.
  - thaumasiotes 10y ago
    > While the statistics are nice to look at, I have read the article you mentioned, too (was on HN a while ago) and instantly thought that metabolism unfortunately renders the whole calculation useless and wrong. Why did you think this? Can you articulate a change that metabolism would make to the calculation?
    - allendoerfer 10y ago
      It adapts, like my parent comment has said. Most of our energy is spend on keeping the system running, not running with our feet. If we start to run, we burn more energy, because our metabolism has not adapted yet, once it adapts (see his example with Africa), there is very little change. Obviously this is simplified.
      - thaumasiotes 10y ago
sfifs 10y ago
Actually not so much surprisingly - the key exceptions being if you are working in very cold climates where the body has to generate more heat to keep you alive or you're training competitively for very physically sports. It turns out that about 70-80℅ of what most people consume goes into simply keeping them alive (research basal metabolic rate & daily calorific requirement) and the impact of "work you do" is only a small variation - with the above exceptions. Also interestingly (unable to search the paper reference on phone) there is research that shows that dramatically different lifestyles like Namib desert nomadic hunter-gatherer vs. typical urban don't actually differ on metabolic rates (accounting for non-fat weight)

TulliusCicero 10y ago

Also, driving your car increases maintenance costs on the vehicle, whereas walking decreases maintenance costs on the 'vehicle' (healthcare).

dogma1138 10y ago

Not really, I don't like cycling in the city (not secure enough about not being plastered by a truck, especially considering how little fuck UK drivers seem to give) so I walk to work for almost 2 years now. I started because I wanted to lose like 8-10lbs during a time when I couldn't exercise regularly at the gym which were lost within about 6 weeks. I walk fast at about 6KM(my gait isn't very long because I wear either jeans or dress pants and I am of average height, but still I'm doing 130-135 steps per minute) an hour according to Google Fit/Apple Health, and I walk between 11-15KM a day (~2-2.5 hours I take a longer route through Hyde Park if the weather is nice and I'm not in a rush getting to or from work). This daily walk alone increased my daily rough caloric requirement to about 2800-3000 calories, that's 600-800 (k)calories over my daily default if i don't do any physical activity other than getting up and commuting to work on the tube. If i don't increase my caloric intake i would lose between 0.5 and 1 KG a week so in this case and in every other case the "food expenditure" isn't a sunk cost, now you might say that my caloric intake doesn't have much impact on the grand scheme and you would be correct, if I need to eat another slice of pizza or another muffin it doesn't affect anything in the long run, if anything it probably means we might "waste" a bit less food. But given the current cost of each food calorie that you intake if everyone all of a sudden goes up to 3000 Kcal daily requirement it will have an effect on the environment and the economy. What you should take from it is not that walking is bad for the environment but is that the global food production is highly inefficient ATM, food is cheap especially in the US but it comes at a pretty big price also.

collyw 10y ago

Yes, it is taking the total calories used (actually its not that clear). It should be comparing the extra calories burned by cycling minus the calories burned sitting. Driving the car, you will still be burning most of those calories as well as burning the gasoline.