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Scientist busts myths about how humans burn calories

science.org

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Re: Scientist busts myths about how humans burn calories

#181

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.

How is it ambiguous. You clearly understood I meant calories burned per unit time.

Re: Scientist busts myths about how humans burn calories

#183

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…

> 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,…

Most people can't manage to burn 1000 kcal in a 60 minute workout. I am a large man in fairly good shape and have to put in a pretty hard effort to hit those numbers. People who are smaller or not well trained are going to be significantly lower.

Measuring stationary bike workouts in terms of mph is kind of meaningless. What actually matters is the measured power output based on the resistance setting.

Re: Scientist busts myths about how humans burn calories

#184
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…

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Re: Scientist busts myths about how humans burn calories

#185

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…

After a 2000 kcal high intensity cycling workout I'm so tired that I don't even feel like eating. I have to force myself to eat something because I know I need it for recovery.

Re: Scientist busts myths about how humans burn calories

#186
post #114

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.…

Fasting isn’t a mood killer, it actually has the opposite effect. IF gives me an energy boost and associated euphoria.

Re: Scientist busts myths about how humans burn calories

#187
Since the article is comparing non-fat mass is this saying that someone with 60kg of non-fat mass will burn the same amount of calories if 1. their overall mass is 75 kg and they're athletic or 2. have more fat mass being 85 kg overall and non-athletic? I'm not sure what i'm missing but that isn't shocking or surprising. I feel like someone's trying to pull a fast one here.

"female farmers in western Africa used the same amount of energy daily when adjusted for fat-free body mass as women in Chicago —about 2400 kilocalories for a 75-kilogram woman. "

Re: Scientist busts myths about how humans burn calories

#188
post #166
post #137

Earlier quoted context omitted.

I have also done almost exactly this process, and it worked for years to regulate my weight. But then I hit a plateau (a high plateau, not a low one) where I was unable to drop weight no matter how low I cut my calories. I started at a range that I knew had worked in the past, and lowered it over the course of weeks, well past the point where I was miserable. I even tried more complicated things, like varying my inta…

The most likely possibility is that you were simply underestimating your calorie consumption. A lot of people forget to count the creamer in their coffee, the candies from the office break room, the little tastes while cooking dinner. Unless you have a severe metabolic disorder your body will only burn lean muscle mass as a last resort when you have exhausted glycogen stores and can't sustain the energy demand from f…

I explicitly overshot the goal by more than 500 calories. Yes, there are always mistakes in estimation, but that isn't what was happening. Remember, I've done this before successfully.

Re: Scientist busts myths about how humans burn calories

#189

Earlier quoted context omitted.

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 t…

For the majority of regular people feeling tired and worn out is more likely to be caused by lack of sleep and too much booze than by lack of food or excessive exercise.

Re: Scientist busts myths about how humans burn calories

#190
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…

> It took me several decades too long to understand the obvious, that exercise is for building strength, and losing weight happens by eating less.

Exercise does much more, and does have some impact on weight, according to the next paragraphs of the article:

But Thyfault warns that message may do more harm than good. People who exercise are less likely to gain weight in the first place, and those who exercise while they diet tend to keep weight off better, he says. Exercise also can impact where fat is stored on the body and the risk of diabetes and heart disease, he says.

Pontzer agrees that exercise is essential for good health: The Hadza, who are active and fit into their 70s and 80s, don’t get diabetes and heart disease. And, he adds, “If exercise is tamping down the stress response, that compensation is a good thing.” But he says it’s not fair to mislead dieters: “Exercise prevents you from getting sick, but diet is your best tool for weight management.”

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