Scientist busts myths about how humans burn calories • Hacker News Board

Re: Scientist busts myths about how humans burn calories

#201

Post by throwaway09223 » Fri, Feb 18, 2022, 5:45 AM UTC

dpark wrote: post #143

throwaway09223 wrote: post #130

Earlier quoted context omitted.

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.

It was measuring women who were sedentary and trained for half marathons. For someone who was previously sedentary, 3.4 miles/day is an enormous amount of exercise. It’s certainly far more than the average American gets. It’s not that much in terms of calories. It is a lot of physical activity for a modern human in a developed nation.

Yes, but "the tiny amounts of exercise typical overweight Americans engage in won't help" is a very different statement than "you can't exercise your way out of obesity" or "you can't outrun a bad diet." The latter is categorically false.

Re: Scientist busts myths about how humans burn calories

#202

Post by sdoering » Fri, Feb 18, 2022, 5:49 AM UTC

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…

I know, anecdata, but on my off dates (I go swimming in the early morning three days a week) I have to fight not eating breakfast early and then needing lunch and dinner in the evening.

On my swim-days I have no problem with a late breakfast leading me to be able to skip lunch and enjoy my dinner.

But I have no other insight as my own experience.

Re: Scientist busts myths about how humans burn calories

#203

Post by leksak » Fri, Feb 18, 2022, 5:49 AM UTC

timr wrote: post #137

nu11ptr wrote: post #93

Earlier quoted context omitted.

If you fall into a routine CICO isn't that difficult in practice. First, while sleep/stress definitely impact the equation unless you are at an unusual life crisis, the ups and downs mostly balance out over time. Second, I don't recommend counting calories, at least not in the traditional way. Instead, eat a fairly standardized diet at least on a weekly basis, so roughly the same meals (doesn't have to be exact). Eat…

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…

For how long were you in a deficit before plateuing? There are some adaptations the body will make with regards to the thyroid that'll drastically lower your BMR

Re: Scientist busts myths about how humans burn calories

#204

Post by it_does_follow » Fri, Feb 18, 2022, 5:50 AM UTC

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…

If you train for endurance sports you'll definitely lose weight without much attention to your diet.

For example, with marathon training, once you start to hit the 6 plus mile your daily run eats up over 1,000 calories.

Near the end of your training your long run days become over 2,000 calories, and even your easy runs becomes 1000+.

That's essentially an entire extra meal, and you're running 5-6 days a week.

If you're just going to the gym for 30-45 minutes, 3-4 days a week, diet will be essential to losing weight. But if you're running 1 hr + a day and 2+ hrs at least once a week it's hard to get enough calories.

Re: Scientist busts myths about how humans burn calories

#205

Post by throwaway09223 » Fri, Feb 18, 2022, 5:50 AM UTC

ngngngng wrote: post #158

throwaway09223 wrote: post #118

Earlier quoted context omitted.

> 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,…

An hour will replace a third of a healthy persons diet. Fats are the secret to obesity, hands down. I have a remarkably small appetite and I can easily down 1000 calories of ice cream in a single sitting (a single pint of Ben and Jerry's. You can row like crazy for 30 minutes, but if you have two extra candy bars, it's meaningless.

Avoiding calorie dense foods is big, yeah. But exercise is exercise and at higher levels (1+ hour/day) the caloric burn is very significant compared to baseline metabolic rates.

Yes, our bodies are built to take in more calories than we can burn (thankfully!), but if you keep your eating habits constant the exercise will make a huge difference.

Re: Scientist busts myths about how humans burn calories

#206

Post by throwaway09223 » Fri, Feb 18, 2022, 5:53 AM UTC

nradov wrote: post #183

throwaway09223 wrote: post #118

Earlier quoted context omitted.

> 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.

I'm a 40 year old guy who's been sitting behind a desk writing software for two decades. I was in good shape in my 20s but haven't exercised significantly in a very long time.

It took me about three months to get up to that speed, cycling every other day. I started out doing 10 miles, at 10mph.

Three months isn't all that long for an exercise program.

Re: Scientist busts myths about how humans burn calories

#207

Post by leksak » Fri, Feb 18, 2022, 5:53 AM UTC

nradov wrote: post #157

_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…

You have a few correct points but are mostly spreading misinformation. Repeated exercise will only improve efficiency by a few percent at most, and then only for certain activities. For cycling, efficiency hardly improves at all. The calories shown on gym equipment are often nonsense but the latest generation of fitness trackers are reasonably accurate and can be worn 24/7. You have to get into really long cardio ses…

> latest generation of fitness trackers are reasonably accurate and can be worn 24/7.

I've heard claims of 30% inaccuracy. Not sure if that applies to the absolute latest generation but I'd be happy to know if my understanding is outdated

Re: Scientist busts myths about how humans burn calories

#208

Post by lmm » Fri, Feb 18, 2022, 5:53 AM UTC

kinghtown wrote: post #113

KennyBlanken wrote: post #94

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…

I spent years failing to lose weight through diet. I took up endurance cycling and in one day (13 or 20 hours) I burn off a kilo or more, even with the increased eating. Afterwards I'll put that back on in about two months, but as long as I keep doing one or two of these events every month I come out ahead.

I don't know how things are for anyone else, but it worked for me, shrug.

Re: Scientist busts myths about how humans burn calories

#209

Post by esyir » Fri, Feb 18, 2022, 5:54 AM UTC

hombre_fatal wrote: post #164

esyir wrote: post #51

Earlier quoted context omitted.

Are you sure, I get a one or two kg swing, but 5kg of weight seems a bit extreme. I'm not American, but in my part of the world people tend to have gradual trends to weight, not sudden swings.

Weigh yourself with a digestive tract full of food and water, then weigh yourself after fasting for a day. At 200lbs I can swing the scale 15lbs/6+kg. Fat people can probably swing some serious numbers.

Seems like a pretty unusual swing though. Gorging then fasting is certainly not typical behavior.

I can see this happening given such behavior, as well as in the "heavier" portion of the population. definitely not a common occurrence across the population though.

Re: Scientist busts myths about how humans burn calories

#210

Post by bsder » Fri, Feb 18, 2022, 5:55 AM UTC

timr wrote: post #137

nu11ptr wrote: post #93

Earlier quoted context omitted.

If you fall into a routine CICO isn't that difficult in practice. First, while sleep/stress definitely impact the equation unless you are at an unusual life crisis, the ups and downs mostly balance out over time. Second, I don't recommend counting calories, at least not in the traditional way. Instead, eat a fairly standardized diet at least on a weekly basis, so roughly the same meals (doesn't have to be exact). Eat…

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…

> 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.

Fat cells "remember" their metabolic environment when they were created--ie. they "remember" your weight and fight you when you try to reduce it. It's one of the problems with dieting to large weight losses.

It is somewhere around 3 years for a fat cell to die off and be replaced. You probably need to "hang out" at the plateau weight for a bit until the fat cells that remember you being heavier die off.