If fat is stores of energy, then why aren’t fat people more energetic than skinny people?


If fat is stores of energy, then why aren’t fat people more energetic than skinny people?

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They’re long-term stores that can’t be quickly and readily transformed from fat back to energy. Pretty much the body is trading having easy access for having access to more reserves.

So this is a broad generalization as there are people with stores of belly fat who are energetic and active and also individuals who lack those same fat stores and are lethargic.

Nevertheless, I’m going to take a shot at this question. People with large stores of fat get those fat stores mostly by not being active. You’re looking at the process backwards.

They don’t have the fat in order to be more active later; they got fat by not being active now.

Think of being fat like carrying around a backpack full of cans of food. In case of emergency, you can open the backpack, and take out a can, and use that to eat. But in the mean time, you have a heavy backpack that you have to take with you everywhere, and it weighs you down.

Being energetic has to do with how much energy you can expend over a ~short period of time. Fat is stored energy but having that energy in storage doesn’t mean you can expend it any faster.

A metaphor that might work: imagine a huge, giant jug filled with water compared to a smaller jug. Over a short period of time, it’s hard to get that much water out of the giant jug, because it’s hard to carefully tip over and pour. But overall, there’s more water in the bigger jug, and you can go for longer without needing to refill it.

Your body can burn sugar/carbs at a much higher rate per hour compared to fat. If I were to base it on my personal experience, I can burn 600 calories per hour when I eat normally, but doing 250 – 300 an hour on my keto diet is nearly impossible

The body is very efficient at using energy (ie it can go a long way on relatively little energy), and every body (except those suffering extreme starvation) has sufficient energy reserves to go for a few weeks. So storing a bit of extra energy won’t make you more energetic, it will just weigh you down and make it harder to move.

As you get even fatter though, the situation can worsen for another reason. The body tends to store fat when you overeat carbohydrates. The way it does this is that it uses insulin to convert excess blood sugar to fat. But when the body is awash with insulin it cannot access its fat stores for energy. People can get into a vicious cycle where they snack on carbs all day, so their blood sugar keeps spiking, so their insulin is permanently raised, so they can not access their fat stores, so they get hungry trying to provide their body with some immediate energy they can use, so they snack on more carbs, and so on. Ie despite all the extra energy they are storing, they can’t actually access it easily so feel less energetic.

There’s a few things to consider here. First, how exactly are we defining energetic. If its who has the most energy stored in their bodies, and could go the longest without eating, then the fatter person is more energetic. If it’s about being very bouncy and moving around a lot, psychology plays a much bigger role than total fat stored would.

Second, and probably more to the point, is the fact that there’s a cause and effect in play. Energetic people gravitate towards more physically active work and hobbies, leading to less total weight gain. Its not a perfect predictor, as I’ve met some fat construction workers that could have kicked my butt in any physical activity, but its a general rule of thumb.

The very reason the fat gets stored in the first place is because they aren’t in need to use the energy they are otherwise consuming, as well as what others have said about the (slower) speed at which fat can be consumed for energy.

This may be a helpful way to think about it: If cars run on gasoline, then why don’t cars with bigger gas tanks go faster? Speed/energy efficiency has more to do with other systems than just the storage tank.

In a starvation situation, people with more fat reserves will be more energetic as their reserves will last longer than someone with less body fat.

Your question presents a false premise, that body fat makes you energetic. It’s stored energy, not magic energy sauce.

Fat has more than twice the number of calories per gram as carbohydrate or protein does which makes it very energy dense, however it’s hard to burn. Think of it like a big log of wood. you can’t just hold a match to a log and light it on fire. It takes time to either chop it down, or build up kindling around it to get a fire going. Fat is the same way, it is great for long term energy storage, but it takes time for the body to make use of that energy, so you can think of it as ‘slow but steady’ where as carbohydrates are more ‘fast energy that lasts half as long’.

When you fast for long periods, the body starts out with a normal fat storing/carb burning metabolism but as the liver and muscles are depleted of glycogen and fast energy, and no new carbohydrates are digested to replace them, eventually your energy levels sag and you feel very lethargic starting about day 2. During this time your body starts to break down the fat into ketone bodies, which your body and brain are able to use as energy. Just like splitting a log into pieces to fit in your fireplace.

The longer the body is in fat burning mode, the better it gets at it and eventually your energy levels return to something approaching normal only the body is getting energy from burning fat instead of carbohydrates.

Ironically once in fat burning mode, if you eat carbs, the body tries to go back to carb burning, and it can make you feel MORE tired and temporarily reduce your energy level until fat burning ramps up again.

why don’t fuel tankers drive faster than ferraris?

lol I am more energetic than them… throw us both on a deserted island and see how long it takes them to start degrading physically mentally emotionally from lack of food lol i be over here chillin

i literally never feel like i dont have the energy to do something, i see skinny people all the time talkin bout I’m tired lol acting lethargic cause they “havent eaten yet today.”

Analogy: A car with a full tank of gas isn’t “more energetic” than a car with a quarter tank of gas….

Cause they’re different kind of fat. White and brown, brown protect against the cold for exemple and quick to release for an caloric need but it’s long and very difficult to built contrary to white fat

A car can only use a certain amount of gas at a time. A car with 12 gallon gas tank wouldn’t go faster if the gas tank was replaced with one that held 120 gallons.

The potential energy is stored as fat. People with fast metabolism can literally turn calories into energy efficiently whereas people with slow metabolism store calories as fat.

Ketosis is a slow process. It is fast enogh to provide energy if you’re bed ridden but it’s not fast enough to maintain something like running. In a recent study I saw, looking at why athletes were not losing weight with restricted calories and high intensity activities, looking for the energy sources in those cases it was shown that in “emergencies” like that the body compensates by shutting down imune system functions and other energy consuming systems and uses the energy thise systems would be using. So in effect your BMR drops massively and you use far less energy than you would otherwise.

They sure are. Fat people stuffed into bomb calorimeters consistently give higher readings than skinny people.