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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

#111

Post by waterhouse »

_9omd wrote: post #65
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…

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 suspect CO2 itself wouldn't suffice.

Re: Scientist busts myths about how humans burn calories

#112

Post by gameswithgo »

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.

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

Re: Scientist busts myths about how humans burn calories

#113

Post by kinghtown »

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…

I always feel there are some methodology issues in sports science studies like small sample sizes or strange metrics.

While I do agree with you that sustained, high level activity requires and burns more calories, I think that the advice coming out of there, exercise is less efficient than diet for weight loss, is going to absolutely be true for the majority of gym goers who quite frankly are phoning it in whenever they work out.

Like, for example, an olympic swimmer may eat 5000-10,000 calories in a day, but they are spending around 4-6 hours a day in a cold pool training at a world class level (body needs to keep warm somehow regardless of effort.) But a normal person may only swim for 20 minutes at a much gentler pace. This person should still be eating in line with calorie guidelines and macros for age/sex.

The reality is that diet needs to be flexible based on results. Not losing weight? Eat fewer carbs or calories. Feeling tired and worn out? Eat more or exercise less based on your physique and goals.

Re: Scientist busts myths about how humans burn calories

#114

Post by urthor »

The thing is, exercise still reduces appetite.

It raises the blood sugar levels as the body supplies the muscles with carbohydrates, and triggers a complementary response in appetite hormones.

Finally, and most importantly:

Exercise releases dopamine.

Dieting is universally a mood killer, because kilo-joule deficit equals starvation.

So whilst it does not directly impact weight loss. It still makes it (a bit) easier.

Plus there are an enormous quantity of other factors in health that are impacted by exercise.

Bodily strength is entirely responsible, for example, for stopping you getting a "bad back."

The less strength you have in your back muscles, the more strain your vertebra and ligaments are under. Hence your body falls apart quickly and more easily.

You definitely need both kilo-joule control and strengthening exercise if you want to keep your life on track.

Re: Scientist busts myths about how humans burn calories

#115

Post by gameswithgo »

PaulDavisThe1st wrote: post #105
nightski wrote: post #92

Earlier quoted context omitted.

It has very little to do with distance. I lose weight much faster with hiit than riding long distance.

"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!

Re: Scientist busts myths about how humans burn calories

#116

Post by gameswithgo »

taeric wrote: post #81
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.

I'm guessing there are very few folks getting fifty miles a day in, and still heavily overweight. Possible, to be sure. Just very unlikely.

I know such a person which is why I mentioned it. That vast range of human physiology is fascinatingly wide. He also is very aerobically gifted, possibly related things. (efficient engine, but not confirmed with testing, maybe just a big engine and loves food)

Re: Scientist busts myths about how humans burn calories

#117

Post by paavoova »

geoduck14 wrote: post #70
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…

>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…

In your example, if you exercise, you can have the pizza as well as the sandwich. This can be significant, because suppose you have those 300 surplus calories 3x/week minus the exercise (not unreasonable, a small snack here and there, right?). 300 calories is about 3 bananas, so it might not even be unhealthy food.

Rough math: 3 * 300 * 4 = 3600 calories surplus/month. A pound of adipose tissue has ~3500 calories IIRC. So you're now gaining a pound of fat a month, and you're not even indulging yourself, really.

In reality, physical activity and diet aren't so steady, so some months you maintain weight, some you lose, and some you gain a lot. But over time it averages out, and you've put on 12lbs in a year.

Re: Scientist busts myths about how humans burn calories

#118

Post by throwaway09223 »

geoduck14 wrote: post #70
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…

>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…

> if I go all out on a row machine for 30 minutes, I'll burn 300 calories.

A stationary bike at a steady 20mph pace is about 500 calories in 30 minutes. That's really significant. An hour will erase about a third of a normal person's diet.

When I used to do heavy training (long distance running, weight training) I would eat close to 8k calories a day and I was in fantastic shape. Eating more was necessary to survive, given how much energy I was expending.

Re: Scientist busts myths about how humans burn calories

#119

Post by hattmall »

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…

>"oxidation done by bacteria that feast on calories your human cells didn't get"?

That would still be part of calories in.

Re: Scientist busts myths about how humans burn calories

#120

Post by dpark »

Fezzik wrote: post #76
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…

The general rule I find helpful is that diet=size and exercise=shape. Being aware of this really helps me limit my food intake even when I’m exercising a ton.

> exercise=shape

That really depends on the exercise you’re doing and what “shape” you’re going for. Putting tons of time into running won’t make someone look like they lift weights. Aerobic exercise is great for health but it mostly doesn’t change anyone’s “shape” except to the extent that it helps them lose weight.

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