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Scientist busts myths about how humans burn calories

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Re: Scientist busts myths about how humans burn calories

#481

Post by irthomasthomas »

me_me_me wrote: post #472
mantas wrote: post #458

Earlier quoted context omitted.

> Your body burns incredibly more energy just "being there" than you burn moving about. Bullshit. My body goes through 1600-ish kcal on an idle day. If I go out on a 4h steady bicycle ride (= 100km), I go through 2000 kcal on ride alone. That’s much more than my body burns just being there.

I don't get it, how is that a myth or controversial. Cutting empty calories is the easiest to remove calories from daily total. Exercise further decreases the ratio of calories in calories out. Bottom line is: calories in - calories out. There are caveats there for sure, like increasing muscle mass increases idle caloric burn. Different types of food have different effect promoting or impeding metabolism.

calories in - calories out was debunked a while ago. Different types of food and diet cause different degrees of weight gain or loss.

For an extreme example compare 100 calories of glucose to 100 calories of fibre, both are types of sugar. The fibre contains an extra electron that acts like a shell, and the body has to expend energy breaking that bond to make it digestible. So most fibre passes through you without affecting your weight.

The most useful measure of food is the Glycemic Load. Not Glycemic Index which is a measure of the net glucose in the food. Glycemic Load is a measure of how the body responds to the food. E.g. cold potatoes have the same calories and GI as hot potatoes, but their measured GL is actually lower, so cold potatoes are better for controlling weight.

Re: Scientist busts myths about how humans burn calories

#484

Post by watwut »

episteme wrote: post #468
watwut wrote: post #420

Earlier quoted context omitted.

> This is not accurate, weightlifting with a reasonably difficult weight for your strength level is one of the most effective ways to burn calories. It wont make you loose weight however. It will likely make you gain weight as your muscles will grow. Which is explicit goal of many guys who start lifting weights.

No, it won't, unless you are eating excess calories. It takes a lot of energy to repair muscles and grow them.

Muscles weight more then fat. This is something that easily and regularly happen. I am not even saying it is bad thing to happen.

Re: Scientist busts myths about how humans burn calories

#485

Post by mantas »

me_me_me wrote: post #472
mantas wrote: post #458

Earlier quoted context omitted.

> Your body burns incredibly more energy just "being there" than you burn moving about. Bullshit. My body goes through 1600-ish kcal on an idle day. If I go out on a 4h steady bicycle ride (= 100km), I go through 2000 kcal on ride alone. That’s much more than my body burns just being there.

I don't get it, how is that a myth or controversial. Cutting empty calories is the easiest to remove calories from daily total. Exercise further decreases the ratio of calories in calories out. Bottom line is: calories in - calories out. There are caveats there for sure, like increasing muscle mass increases idle caloric burn. Different types of food have different effect promoting or impeding metabolism.

Guess what else has massive effect on metabolism? Exercise.

Also, various workouts have a lot of other important effects. Increasing bone strength, improving body resistance to inflammatory processes, developing micro vascular system… simply managing calorie in/out ratio won’t get you any of this. And dropping weight in a dumb way may do more harm than good.

Re: Scientist busts myths about how humans burn calories

#486

Post by inglor_cz »

rdiddly wrote: post #312

Last thing I saw was "The son of two high school English teachers, Pontzer grew up on 40 hectares of woods in the Appalachian bla bla bla..." You know that sentence. So many articles have that sentence. The one where it veers off course to talk about the (usually uninteresting) person who found the thing the article is ostensibly and nominally about. Am I alone in being perfectly happy reading about science for the d…

It is a genre. You may prefer drier style. On occassion, I do as well. But sometimes I enjoy fluffy writing like this, especially in the human-contact-starved covid days.

I would say "live and let live". There is enough written content on the Web for everyone to find their niche.

Re: Scientist busts myths about how humans burn calories

#487

Post by Xcelerate »

The article seems to miss what is (at least to me) the most interesting follow-up question: if exercise doesn’t cause a person to burn significantly more Calories throughout the day to induce weight loss, then what does?

I’m somewhat hard-pressed to believe the answer is diet alone. Anecdotally, when I was running 100 miles per week in college for cross country, I ate three or four giant meals per day and maintained a very low weight. Ten years later, I have an injury that makes most types of exercise difficult, and I’ve observed that I really can’t eat more than one meal per day (dinner), otherwise my weight starts to creep up.

I find it odd that Calories are used in relation to weight gain, because (kilo)calories are a unit of energy, and excess weight is due to excess fat. Is there a simple linear relationship between the extractable energy content in food (as determined by the Atwater system) and the conversion of food components into fat by the digestive system? I find that hard to believe. Shouldn’t we be using a mass balance rather than an energy balance? If you could observe digestion at the atomic level, you would simply quantify which atoms from food end up in fat stores and which leave the body via other processes. Presumably, these atoms could then be bucketed into source categories (e.g. certain types of proteins or carbohydrates). I wouldn’t be surprised if exercise somehow alters the fat accumulation process even if it doesn’t significantly affect human metabolism.

Re: Scientist busts myths about how humans burn calories

#488

Post by bluecalm »

PaulDavisThe1st wrote: post #74
gameswithgo wrote: post #63

Earlier quoted context omitted.

its possible to work out enough that compensative eating is not possible, but very few people work out that much, and some people have amazing eating powers, such that even riding a bike 50 miles a day isn’t enough to stop them being fat unless they also count calories.

Riding a bicycle? It's roughly 5x more efficient than running or walking. If you want to lose weight from cycling, you're going to have ride significantly further than 50 miles a day.

Are you sure about those numbers? Running is about 1kcal/km/kg of body weight. For cycling to be 5x as efficient you would only need 14kcal/km for 70kg man. I don't think it's realistic. The numbers I've seen are closer to 25kcal/km.

Re: Scientist busts myths about how humans burn calories

#489

Post by [deleted] »

PaulDavisThe1st wrote: post #121
gameswithgo wrote: post #112

Earlier quoted context omitted.

Paul, if I am doing 50 miles at 300 watts that isn’t any different than running for two hours. You can set whatever level of intensity you want for the duration. 50 miles a day all out will wear out even olympic athletes. Source: I work with olympic athletes and time trial champions

Sure, 50 miles a day @ 300W is not much different than running for 2 hours at a sub-7min/mile pace. But most people cycling 50 miles are not generating 300W continuously, and most people running for 2 hours are not doing a sub-7min pace for the duration. ps. I have run for 2 hours at a sub-7 min pace, and cycled 50 miles at about 280W.

[deleted]

Re: Scientist busts myths about how humans burn calories

#490

Post by stedaniels »

scotty79 wrote: post #441
jeltz wrote: post #404

Earlier quoted context omitted.

While I agree with that excerice isn't a very efficient way to lose weight I think that you understate how many calories running burns. When I run consistently I need to eat what feels like a lot more food to maintain my weight. Running burns about 700-800 kcal per hour for me (I have a quite small build) which ends up quite a bit over a week (I run 5-8 hours per week).

Think about it this way. The rate at which you burn calories is directly proportional to the rate at which you breathe out CO2 because that what happens with carbon you burn. So if every day you train for an hour so that your breathing is 3 times faster, then you have additional two hours of burning in a day. 23 usual hours plus one worth 3. So you have 26 instead of 24 hours in a day. It's way easier to put 15% less…

You are arguing a different point. They argued that doing exercise burns more calories than sitting idle.

@1_player said: > Your body burns incredibly more energy just "being there" than you burn moving about.

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