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Is this true? Exercise/fat loss question.

Fatvaporizer
Posts: 139 Member
This may sound a bit discouraging, and with many videos and articles that explain how to lose weight in their own ways, this video's reliability and veracity aren't assured. Therefore some clarification would be good.
This specific video that explained how to lose weight said that the first 29 or 30 minutes of exercising doesn't burn body fat, and that it only burns recently eaten food. I find that discouraging because personally, and I'm sure most people exercise a couple hours after they eat. So according to that video, only exercising more than 30 minutes every time would actually make you lose weight?
For example, 45 minutes a day of exercise, and only 15 minutes are actually beneficial since apparently the rest just burned the food you ate. That would mean doing about 1 hour of exercise actually equates to 30 minutes only since the first 30 only burns food and not fat...
Please help clarify this, thank you.
This specific video that explained how to lose weight said that the first 29 or 30 minutes of exercising doesn't burn body fat, and that it only burns recently eaten food. I find that discouraging because personally, and I'm sure most people exercise a couple hours after they eat. So according to that video, only exercising more than 30 minutes every time would actually make you lose weight?
For example, 45 minutes a day of exercise, and only 15 minutes are actually beneficial since apparently the rest just burned the food you ate. That would mean doing about 1 hour of exercise actually equates to 30 minutes only since the first 30 only burns food and not fat...
Please help clarify this, thank you.
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Replies
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No, it's not true. You lose fat by being in a calorie deficit, and that can happen with or without exercise, so the amount of time spent exercising is irrelevant.10
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It's only partially true and not always applicable. Don't worry about that minutia.
Your body will burn some amount (for an example, we'll say 2000) Calories in the course of a day, including exercise. That 2000 Calories will come from body fat, food, and some other tissue in the body - at the same time. Your body will also replenish (at different rates) the body fat and other tissue. It doesn't matter what any one particular thing (breathing, exercise, walking to the bathroom, etc) uses more of at any one particular time - the overall effect will be equivalent.
In short, just trust the process. It works.8 -
The body will, at a certain point, use stored body fat for energy to fuel activity, that much is true.
However, these stores are replenished when we eat so it's pretty moot when it comes to weight loss. The only way to permanently lose body fat is to consistently be in a calorie deficit. So what you put in your mouth is far more important than what you do in the gym.2 -
No, it's not true. You lose fat by being in a calorie deficit, and that can happen with or without exercise, so the amount of time spent exercising is irrelevant.
This. Your body is burning calories all day, every day. It's not like you don't start burning calories until your workout starts and it takes half an hour to burn through your stomach contents. Your body burns calories even when you sleep, to keep your heart beating and your lungs breathing. I'd guess there is something or other about the best conditions for optimal fat burning in the video or something like that, but even if it's true, it's majoring in the minors I think.4 -
Does it matter? The body has to use energy from somewhere, and what's not used gets stored. If it used body fat for fuel at one moment, the food fuel would be stored and vice versa. It all works out the same in the end.1
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You burn calories just by living. The only way to lose fat is to consistently eat less than you burn. It doesn't really matter what you are burning during the exercise..
This is the (not entirely scientific) way I think about it, as an accountant.
Your body sort of "settles up" when you sleep. So you go through your day, moving, eating, digesting and then you go to sleep. If you ate a little more than you burned that day, it stores it in the fat, and to some extent can grow your muscles too if you stressed them enough to grow; if you ate a little less than you burned that day it withdraws it from the fat (and whatever it needs from muscles and organs). Over time these little transactions add up to weight/fat/muscle gained or lost.
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Fatvaporizer wrote: »This may sound a bit discouraging, and with many videos and articles that explain how to lose weight in their own ways, this video's reliability and veracity aren't assured. Therefore some clarification would be good.
This specific video that explained how to lose weight said that the first 29 or 30 minutes of exercising doesn't burn body fat, and that it only burns recently eaten food. I find that discouraging because personally, and I'm sure most people exercise a couple hours after they eat. So according to that video, only exercising more than 30 minutes every time would actually make you lose weight?
For example, 45 minutes a day of exercise, and only 15 minutes are actually beneficial since apparently the rest just burned the food you ate. That would mean doing about 1 hour of exercise actually equates to 30 minutes only since the first 30 only burns food and not fat...
Please help clarify this, thank you.
You're looking at it completely wrong...the energy source used for a particular exercise is completely irrelevant. Our bodies are constantly cycling through energy sources...fat and carbs...the more intense the activity, the more carbs and glycogen are used...the lower the intensity of the activity, the more fat is used...which is why you burn more fat while you're asleep than any other time of day..
But you also have to understand that your body is also constantly storing and burning fat...what ultimately matters for losing weight/fat is your net energy position. When you are in a net deficiency of energy, you will have burned off more fat than you stored in a day.6 -
Well Bejeezers, I very much doubt there is any truth to this at all.
What I'm currently doing is eating at maintenance (sedentary) calories and creating a deficit solely through exercise. And I don't mean athlete level exercise either! All i do is plain and simple walking, I do 30 minute blocks of speed walking all throughout the day, so going by this article it's all just a waste of time... But my weight loss tells another story, as this has been working perfectly for me.
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It hardly matters. Do you save money by using a different bank card when you shop? Nope. It's all your money, no matter which bank account it comes from. And when your body spends energy, it's all the same, no matter where it takes it from - from blood glucose, glycogen or fat, it's the same amount of energy spent, and if there's an overall deficit at the end of the day, then it's going to come out of the fat stores (provided you take precautions to preserve muscle).
People overthink this stuff so much. You don't even need to worry about the difference between glucose, glycogen and fat - that's just book keeping and your body handles it. All you need to worry about is energy in and energy out.2 -
No, it's not true. You lose fat by being in a calorie deficit, and that can happen with or without exercise, so the amount of time spent exercising is irrelevant.
LOL. No wonder people struggle with the basics of weight loss, if this is what they think. How can time spent on exercise be irrelevant? The more you exercise the more energy you expend and therefore the higher your calorie deficit.
That doesn't mean you have to exercise to lose weight, especially if you're very fat, you can simply eat less. But for people like me who are on the lower range of normal weight, or for people who are overweight but don't like to starve themselves on 1200 calories, we are better off eating significantly more while getting our deficit from increased activity. And exercise time and/or intensity are absolutely a direct factor on the calorie deficit.0 -
Traveler120 wrote: »No, it's not true. You lose fat by being in a calorie deficit, and that can happen with or without exercise, so the amount of time spent exercising is irrelevant.
LOL. No wonder people struggle with the basics of weight loss, if this is what they think. How can time spent on exercise be irrelevant? The more you exercise the more energy you expend and therefore the higher your calorie deficit.
That doesn't mean you have to exercise to lose weight, especially if you're very fat, you can simply eat less. But for people like me who are on the lower range of normal weight, or for people who are overweight but don't like to starve themselves on 1200 calories, we are better off eating significantly more while getting our deficit from increased activity. And exercise time and/or intensity are absolutely a direct factor on the calorie deficit.
I took it to mean that the amount of time exercising is irrelevant to when you start "burning fat". You don't have to work out for a certain number of minutes before your body starts burning fat. Yes, obviously, the more exercise you do, the more calories you burn. But the OP's question was do you have to exercise for more than 30 minutes for your body to burn fat.2 -
Traveler120 wrote: »No, it's not true. You lose fat by being in a calorie deficit, and that can happen with or without exercise, so the amount of time spent exercising is irrelevant.
LOL. No wonder people struggle with the basics of weight loss, if this is what they think. How can time spent on exercise be irrelevant? The more you exercise the more energy you expend and therefore the higher your calorie deficit.
That doesn't mean you have to exercise to lose weight, especially if you're very fat, you can simply eat less. But for people like me who are on the lower range of normal weight, or for people who are overweight but don't like to starve themselves on 1200 calories, we are better off eating significantly more while getting our deficit from increased activity. And exercise time and/or intensity are absolutely a direct factor on the calorie deficit.
LOL..but by the bolded I don't think you really get what I'm saying.
None of that changes the fact that you do not need to exercise to lose fat, or weight, or how ever you want to label it. Also exercising is not a basic of weight loss. The basic of weight loss is CICO, how you achieve that, and how healthy you want to be in the process is all after the fact. So I would say your thinking is probably why so many people struggle with the basics of weight loss, and think that if they workout 29 minutes or less, they are only burning the food they just ate, and it was all for nonthing.
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Fatvaporizer wrote: »This may sound a bit discouraging, and with many videos and articles that explain how to lose weight in their own ways, this video's reliability and veracity aren't assured. Therefore some clarification would be good.
This specific video that explained how to lose weight said that the first 29 or 30 minutes of exercising doesn't burn body fat, and that it only burns recently eaten food. I find that discouraging because personally, and I'm sure most people exercise a couple hours after they eat. So according to that video, only exercising more than 30 minutes every time would actually make you lose weight?
For example, 45 minutes a day of exercise, and only 15 minutes are actually beneficial since apparently the rest just burned the food you ate. That would mean doing about 1 hour of exercise actually equates to 30 minutes only since the first 30 only burns food and not fat...
Please help clarify this, thank you.
As mentioned, you lose weight by calorie deficit. Exercise helps to create it, so don't worry about how much fat you're burning. Focus on how many calories you're burning.
A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 30 years and have studied kinesiology and nutrition
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Traveler120 wrote: »No, it's not true. You lose fat by being in a calorie deficit, and that can happen with or without exercise, so the amount of time spent exercising is irrelevant.
LOL. No wonder people struggle with the basics of weight loss, if this is what they think. How can time spent on exercise be irrelevant? The more you exercise the more energy you expend and therefore the higher your calorie deficit.
That doesn't mean you have to exercise to lose weight, especially if you're very fat, you can simply eat less. But for people like me who are on the lower range of normal weight, or for people who are overweight but don't like to starve themselves on 1200 calories, we are better off eating significantly more while getting our deficit from increased activity. And exercise time and/or intensity are absolutely a direct factor on the calorie deficit.
The number of calories you burn is absolutely relevant. The time spent in purposeful exercise is irrelevant except to the extent to which it contributes to your overall calorie burn.0 -
It's half true. However I read that 30% of the calories burned is/can be burned via physical activity. So the other 70% is your body burning off calories, which is why you have to eat under a certain amount.0
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humpbackgirl wrote: »It's half true. However I read that 30% of the calories burned is/can be burned via physical activity. So the other 70% is your body burning off calories, which is why you have to eat under a certain amount.
What? Are you referring to a nonBMR:BMR ratio of some sort?1
This discussion has been closed.
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