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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

#121

Post by PaulDavisThe1st »

gameswithgo wrote: post #112
PaulDavisThe1st wrote: post #74

Earlier quoted context omitted.

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.

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.

Re: Scientist busts myths about how humans burn calories

#122

Post by bena »

dahart wrote: post #4

> “You can’t exercise your way out of obesity,” […] “you can’t outrun a bad diet.” While this article is being a bit dramatic and possibly understating the impact of exercise slightly, I feel a little dumb that I didn’t know this earlier. It took me several decades too long to understand the obvious, that exercise is for building strength, and losing weight happens by eating less. I tried for way too many years to ex…

Yeah. A single snickers is over 200 calories. That's 30 minutes of running.

Eating is incredibly efficient.

Re: Scientist busts myths about how humans burn calories

#123

Post by PaulDavisThe1st »

gameswithgo wrote: post #115
PaulDavisThe1st wrote: post #105

Earlier quoted context omitted.

"much faster" is ambiguous here. Ride 150 miles a day every day for a week, don't over-eat, and you will lose much more weight than you ever could from HIIT. On the other hand, that's a lot of hours, and HIIT will easily win in terms of weight-loss per unit time.

Paul, you can lose all of your weight without working out at all!

You don't know anything about my weight! :))

For sure. But the discussion going on here (and in TFA) is the balance between weight loss via exercise and weight loss via lower calorie consumption.

Re: Scientist busts myths about how humans burn calories

#124

Post by Retric »

PaulDavisThe1st wrote: post #72
_9omd wrote: post #65

Earlier quoted context omitted.

I think a big part of the issue is that popular fitness and weight loss advice has perpetuated the wrong way to exercise to loose weight. When most people think about exercise for weight loss, they imagine long exhausting sessions on the treadmill, dripping with sweat, and a high calorie burn number. While the short term results may seem great based on the immediate calories burned, it's actually a terrible strategy…

> 2) Your hunger will increase to compensate for the calories burned and you'll subconsciously eat more if not carefully tracking. This is also a oft-made claim that doesn't have much backing. Part of the point of the research described in TFA is that humans who face specific periods of energy expenditure during the day may often simply reduce energy expenditure during the rest of the day so that TEE remains roughly…

It has a lot of backing when you look at people changing jobs without gaining or losing weight. We think of exercise in terms of X minutes on a treadmill, but people working long days of physical labor can more than double their daily caloric needs and will eat accordingly without prompting.

There where plenty of old jokes about lumberjack breakfasts and people eating skills tall stacks of pancakes. These guys weren’t trying to gain or lose weight just keep going for another day of hard labor, but when you start talking 6-8,000 calories per day it’s an insane amount of food.

Also, some of the feedback mechanisms involved are quiet slow and can take weeks to kick in. Your body doesn’t need to balance things every day as gaining or losing significant weight takes time.

Re: Scientist busts myths about how humans burn calories

#125

Post by throwaway09223 »

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.

I ride 20-25 miles a day on a stationary bike, at about 20-25mph steady rate. It burns a bit over 1000 calories during the hour. It's more than enough to make a significant change, especially when paired with a half hour of weights.

Re: Scientist busts myths about how humans burn calories

#126

Post by rdtwo »

KennyBlanken wrote: post #94
geoduck14 wrote: post #70

Earlier quoted context omitted.

>A lot of people know this already, so it’s not busting everyone’s myths It is still worth mentioning - because it is so easy to overlook. Some simple math: if I go all out on a row machine for 30 minutes, I'll burn 300 calories. If I eat 2 extra slices of pizza, it is easiely 300 calories If I swap a turkey sandwich with healthy options, I can reduce my linch calories by 300 - and I can save even more during dinner…

A few hours on my bike can be 2,000-3,000 additional calories over base metabolic rate. That's not based on made-up calories but actual work from a power meter on the bike. "You can't exercise your way out of a bad diet" - literally not true for a fuckton of endurance-sport athletes for whom the challenge is eating enough calories. It's 100% true for people who think exercising for 30 min means license to eat whateve…

No post body was provided.

Re: Scientist busts myths about how humans burn calories

#128

Post by taeric »

anchochilis wrote: post #96
taeric wrote: post #37

Earlier quoted context omitted.

Yeah... I don't know that it is that simple. In the summer when I bike twenty miles a day, I am eating far more, and still losing weight. Don't get me wrong, I know that the easiest way to lose weight is to limit calorie consumption. I also know that a buffet of 1800 calories going to a bike ride helps a ton.

Yeah, for a few years in my 20s I was bike commuting 24 miles/day and running 6-10 miles/day on top of that, with longer runs or hikes on the weekends. I was in the best shape of my life, felt great and ate whatever I wanted without thinking about it. BUT I was spending 4 hours per day exercising. Now I have a 6 week old baby and WFH... I manage a 30 minute Peloton a few times a week. Maybe. Even though I try to pay…

Some of that is just being in your twenties. :). Pretty sure just thinking of a hike lost weight back then.

Re: Scientist busts myths about how humans burn calories

#129

Post by _9omd »

waterhouse wrote: post #111
_9omd wrote: post #65

Earlier quoted context omitted.

I think a big part of the issue is that popular fitness and weight loss advice has perpetuated the wrong way to exercise to loose weight. When most people think about exercise for weight loss, they imagine long exhausting sessions on the treadmill, dripping with sweat, and a high calorie burn number. While the short term results may seem great based on the immediate calories burned, it's actually a terrible strategy…

> measuring calories out is extremely difficult unless you're willing to live in a sealed room that monitors your exhaled CO2 24/7 Is even that sufficient? Like, would you be able to tell the difference between "oxidation done by the body to generate energy for human cells" and "oxidation done by bacteria that feast on calories your human cells didn't get"? Maybe you could tell by the mixture of other gases, but I su…

Yeah, that's a very good point. This is kinda getting off into the weeds from the original point, but interesting weeds nonetheless :).

This study[0] says that measuring CO2 is not enough, and that indirect calorimetry is the gold standard for measuring energy expenditure (EE).

"Calculated EE based on CO2 measurement was not sufficiently accurate to consider the results as an alternative to measured EE by indirect calorimetry. Therefore, EE measured by indirect calorimetry remains as the gold standard to guide nutrition therapy."

Google says "Indirect calorimetry is the method by which measurements of respiratory gas exchange (oxygen consumption, V O 2 and carbon dioxide production, V CO 2 ) are used to estimate the type and amount of substrate oxidized and the amount of energy produced by biological oxidation."

So getting back to your point, if bacteria are feasting on part of the calories and producing CO2, it seems that it would throw off the results even using indirect calorimetry. At that point though are we kinda arguing semantics? While our microbiome isn't composed of human cells, you can still argue it's a part of our functioning organism. It seems it would be nearly impossible to measure human digested calories vs bacteria digested calories, so maybe the results are close enough. Also, many beneficial bacteria release calories that we can consume, like butyric acid, which further complicates things.

[0] https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC5251283/

Re: Scientist busts myths about how humans burn calories

#130

Post by throwaway09223 »

dpark wrote: post #99
dahart wrote: post #43

Earlier quoted context omitted.

That’s the part that’s at least slightly exaggerated, or giving a misleading impression. Exercise absolutely burns more than 0 calories, and I definitely was burning some. Calorie burn from exercise is straightforward to approximately measure, and many people walking around with iWatches and FitBits and heart monitors are doing so. What’s well known to many people is that exercise burns far fewer calories than you wi…

I would really like to see raw data because it feels like the story being told can’t possibly be complete. This in particular feels really hand wavy: “After weeks of training, they barely burned more energy per day when they were running 40 kilometers per week than before they started to train.” What does “barely” mean? 40km/week isn’t that much in terms of calorie burn. The 100 calories/mile rule of thumb says this…

40km/wk is only 3.4 miles/day. It's only a half hour of moderate exercise a day. It sounds like the study didn't actually measure a significant exercise workload.
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