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Thinking hard burns almost no calories but destroys your next workout

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Re: Thinking hard burns almost no calories but destroys your next workout

#131

Post by mamcx »

soared wrote: post #118
evanjrowley wrote: post #112

Balancing health while being productive as an average adult seems like an impossible equation today. Many people tell me I need to lift weights to lose weight. On mornings when I actually put in real effort, I pay for it with a significant cognitive performance penalty for the remainder of the day. I want to do nothing more than sleep an hour after a workout, which is bad timing, because that's when I need to clock i…

Hate to be the bearer of bad news, but you are likely over training. Check out heart rate zones, optimal workouts for weight loss/muscle gain. IE for endurance sports most of your training time should be zone 2, which if casually “a level of breathing where you could have a conversation”. So not breathing hard. It’s counterintuitive, but you should do workouts pretty close to easy.

Yeah, in special if you "stop-start-stop" constantly.

Give time to ramp-up. I like to start 2-3 days with things like the "7 minute workout" before dive in into anything more complicated.

Is better quantity than "quality" until you actually can put the discipline and consistency. If not, just walk is good enough

Re: Thinking hard burns almost no calories but destroys your next workout

#132

Post by BobaFloutist »

Nevermark wrote: post #111
helsinkiandrew wrote: post #105

Earlier quoted context omitted.

> That's what I mean by "myth" - not that exercise burns zero calories, but that the popular mental model of "I ran for an hour so I earned X calories of food" is built on inaccurate measurements Over the last few of decades there's been a lot of lab research calculating the gross efficiency of the human body with different factors (size, sex, fitness etc) and I think these estimates that sports apps give are very cl…

To the degree the body diverts any housekeeping or thermogenic calories to exercise calories, which from basic biological adaptivity and thermogenic control must be true at some level, that math will be misleading. Not that doing x work doesn’t burn y energy, but that +x work in exercise does not burn +y energy at the end of the day. Exercise is an alternate heat source, approximately 1-to-1 with thermogenic heat (al…

>It is interesting that during periods in which I have a habit of daily low intensity exercise, I feel like I have more energy than periods I don’t do any exercise, even if my calorie intake is the same.

In the same vein as much of the rest of what you're saying, the other thing that I feel like people always neglect with their "Calories in/calories out" and "Bodies can't violate thermodynamics" is that the human body can adjust how efficiently it processes food, colloquially known as a "slow" or "fast" metabolism.

While it's true that the human body has no answer to a true calorie deficit (except the incredibly powerful and effective one of tweaking satiety and hunger signals), as long as you're eating more calories than you're strictly burning, your body can simply take longer or less time to digest the food you put into it and extract more or less energy from what you're eating, which can make an enormous difference without you changing your intake at all. Which means that people can absolutely eat identically, have identical appetite levels, and have extremely different body types.

If you're exercising more, sure, your body will make you more hungry, but it will also work harder to squeeze every possible calorie out of what you're already eating. If you cut down on what you eat, your body will work even harder at it, to the point that you could literally eat less, work out more, feel hungry and tired all the time, while getting fatter, because your body is worried that you're in a famine and in a physically stressful environment and is desperately trying to signal to you to conserve as much energy as possible, eat as much as possible when you find food, and at the same time trying its best to make the most of the food you give it.

And at the same time, someone else's body might simply not do that. It's crazy!

Re: Thinking hard burns almost no calories but destroys your next workout

#133

Post by BobaFloutist »

tsimionescu wrote: post #110
SubNoize wrote: post #90

Earlier quoted context omitted.

For cardio sure but for weight training you're burning calories and tearing muscle fibres to increase size/strength. Also depending on the running you're doing, you're likely staying fitter. Sure it's easier to fast but you're missing out on the other benefits associated with exercise.

> Sure it's easier to fast but you're missing out on the other benefits associated with exercise. This is very true, exercise is very important for health regardless of its effect on weight. > For cardio sure but for weight training you're burning calories and tearing muscle fibres to increase size/strength. True, but you need to spend even more time to rack up 800 Cal worth of exercise by weight training compared to…

Yeah, unfortunately back of envelope physics math about the kC burned for lifting weights is deeply disappointing. Luckily our bodies are quite inefficient compared to a bomb-calorimeter, because back of envelope gets me less than a (k)calorie per 3 sets of 5 lifts, if you just do lazy potential energy math.

Re: Thinking hard burns almost no calories but destroys your next workout

#134

Post by BobaFloutist »

soared wrote: post #119
PleasureBot wrote: post #117

Earlier quoted context omitted.

There's been metabolic studies that show that this isn't true. Comparisons of total caloric usage of completely sedentary people and people who have high exercise load are indistinguishable. There is a large difference among individuals, but not correlated to exercise levels. Sedentary people who start training hard will have a spike in caloric usage for a few months, but their body adapts and calorie burn returns to…

Absolute nonsense. The claim is that if I produce 2.5watts per kg in body weight for 2 hours, I’m not going to burn any extra calories? So when I “bonk” and exhaust glycogen stores due to underfueling that’s actually not true?

I think that the claim is that what you're experiencing absolutely does happen, and your body responds by cutting corners on your baseline when you're sleeping or sitting around on the couch to avoid you starving to death (because it doesn't know that you can trivially increase your food intake if needs must).

Re: Thinking hard burns almost no calories but destroys your next workout

#135

Post by Nevermark »

BobaFloutist wrote: post #132
Nevermark wrote: post #111

Earlier quoted context omitted.

To the degree the body diverts any housekeeping or thermogenic calories to exercise calories, which from basic biological adaptivity and thermogenic control must be true at some level, that math will be misleading. Not that doing x work doesn’t burn y energy, but that +x work in exercise does not burn +y energy at the end of the day. Exercise is an alternate heat source, approximately 1-to-1 with thermogenic heat (al…

>It is interesting that during periods in which I have a habit of daily low intensity exercise, I feel like I have more energy than periods I don’t do any exercise, even if my calorie intake is the same. In the same vein as much of the rest of what you're saying, the other thing that I feel like people always neglect with their "Calories in/calories out" and "Bodies can't violate thermodynamics" is that the human bod…

> your body can simply take longer or less time to digest the food you put into it and extract more or less energy

Great point.

> If you're exercising more, sure, your body will make you more hungry, but it will also work harder to squeeze every possible calorie

I find when I only do light exercise, that I am less hungry than when I don't exercise. Perhaps because I get better sleep, I am less hungry.

All the dynamics are crazy.

Re: Thinking hard burns almost no calories but destroys your next workout

#137

Post by Rapzid »

raincole wrote: post #53
Rapzid wrote: post #41

Earlier quoted context omitted.

Chess lol. Playing a competitive arena FPS a the highest levels will get your brain cooking.

Don't know what's here to 'lol' about chess. Are you implying chess isn't cognition intensive?

I'm suggesting there are other activities I'd expect to cause the brain to burn more calories.

Re: Thinking hard burns almost no calories but destroys your next workout

#138

Post by rpdillon »

xnorswap wrote: post #45
nick486 wrote: post #36

Earlier quoted context omitted.

I think it sort of depends on how you look at it. If 800 is an hour of running - that's probably "a lot" for quite a few people. But 800 is also just a sandwich. Which isn't all that much. So if you view this from a time use perspective, just skipping that sandwich is way better than running for an hour. And many people can't spare an hour a day just to make up for a sandwich. Hence - "not a lot" - Its too expensive…

What kind of sandwiches are you eating? 800 calories is a ridiculously large sandwich. Even Tesco's bacon & egg triple is only 550 : https://www.tesco.com/groceries/en-GB/products/260422235 I'm struggling to find anything I'd describe as a sandwich come close to 800 calories.

Footlong Spicy Italian at Subway ($10 sandwich) is 1320 cals.

EDIT: the trend holds pretty well at the footlong size (which is a big sandwich). 18/26 sandwiches they offer are >1000 calories.

Re: Thinking hard burns almost no calories but destroys your next workout

#139

Post by Izkata »

jahnu wrote: post #65
tsimionescu wrote: post #60

Earlier quoted context omitted.

You need to eat roughly somewhere between 1300 and 2000 Cal every day to maintain your weight even if you are doing to exercise at all. If you want to lose weight, it's far easier to remove 800 Cal from your diet, at least time wise, then it is to exercise 800 Cal's worth every day. Either way, if you're losing weight at any appreciable rate, you will feel hungry (at least if it's not chemically induced in some way,…

> If you want to lose weight, it's far easier to remove 800 Cal from your diet, at least time wise, then it is to exercise 800 Cal's worth every day. That I absolutely agree with and so do my legs ;) I only found the suggestion that exercise _doesn't_ burn calories a bit weird. > you will feel hungry That I also agree with... all this talk of sandwiches!

> I only found the suggestion that exercise _doesn't_ burn calories a bit weird.

I mean... No one said that? The very first comment was about how it's not a lot / not as much as people think, not that it's none.

Re: Thinking hard burns almost no calories but destroys your next workout

#140

Post by Izkata »

BobaFloutist wrote: post #134
soared wrote: post #119

Earlier quoted context omitted.

Absolute nonsense. The claim is that if I produce 2.5watts per kg in body weight for 2 hours, I’m not going to burn any extra calories? So when I “bonk” and exhaust glycogen stores due to underfueling that’s actually not true?

I think that the claim is that what you're experiencing absolutely does happen, and your body responds by cutting corners on your baseline when you're sleeping or sitting around on the couch to avoid you starving to death (because it doesn't know that you can trivially increase your food intake if needs must).

Yes, it's in what they're responding to:

> The authors hypothesized that it could be that the body reduces caloric spend on other things, like stress responses

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