How the body burns fat

Too complicated. Not even sure an answer exists. Don't worry about this part.


No. Although it's complicated, I'm pretty sure this is not how it works.

As I understand it, fat is primarily "burned" through oxidation. The more oxygen you can get your body to use, the more fat you'll lose. That's why short bursts of high intensity loads on the body are a very good way to lose fat; you're using tons of oxygen after those bursts to reload and repair your body for next time.

Don't worry about calories. Worry about getting enough fiber and controlling your carbs. Most everything else will take care of itself.

carbs, which are converted into simple sugars, are used as a source of energy first. each particle of sugar is burnt up and converted into calories for the body's use, whether it's for normal body functions, or for exercising, etc. fats are the secondary source and muscle is last in the pecking order. i agree with ken. control your carb intake and the fat will melt away. make sure you're eating enough because if you don't, your body start breaking down precious muscle.

i'm not sure about "spot toning", but if you're trying to tone your midsection (as most of us do) and are seeing results, i think it's mostly because the midsection is the area where most of our fat is deposited. i'm sure someone can ring in with the truth about "spot toning".

also know that fat cells aren't ever "destroyed", even when they are used up as an energy source. the body sees that making fat cells expends a lot of energy, so it has devised a way to become more energy efficient as we evolve.

in lay terms, think of the fat cell as being "deflated" when the body uses it as an energy source. when the body takes in too much carbs/sugar, the body converts the sugar into a storable energy and "re-inflates" the fat cell with that energy. viola! the body does not need to make another fat cell and waste precious energy on making new cells all the time. this is the reason why diets don't work unless they become lifestyle changes and re-gaining weight is almost a certainty after a person discontinues their "diet".

for those who understand this very complicated process and balance between energy expenditure and storage, please know that this is just a conceptual explanation. this is not the exact method the body uses to expend and store fat as energy sources. just trying to help. not looking for anyone to flame.

i'm sorry to rain on your parade, but spot reduction is a myth. your body typically burns fat from all around. keep up the hard work, though.

+1 There is no such thing as spot toning.

so don't eat too much carbs

I think you mean spot-fat reduction; technically true.

Oops. You're right. My mistake.

+1 to all the spot-fat reduction is a myth comments. The body 'chooses' to burn what's most available. The latest research shows that either low-fat or low-carb diets will lead to fat loss as long as they are energy restricted. That said, long term effects of low-carb diets have yet to be determined outside of social pockets that don't have easy access to carbs (Inuit, etc.). It's rare for the human body to consume its own established muscle tissue. That only happens way down the line with malnutrition and ketosis. DDSJohnny is on top of things with his answers, with the caveat of what I've written above. The human body has not adapted to a sedentary lifestyle. It still has issues with red meat and milk, for example. Thus, it doesn't know that you are getting regular meals. The best plan is for it to absorb what it can while it's available and shunt most of it to storage. Mike, fat loss has nothing directly to do with how hard your heart is working. Your body is built to deposit fat in certain places in a certain order. It's different for everyone, but for most males, the stomach and 'love handles' are the last to go because that's an easy place to keep fat out of the way when you go around on all-fours. Look at gorillas for a good example that's not too far removed from H. sapiens. The more you work out while keeping your intake kcal lower than your used kcal, the quicker even these last deposits will go away. Let me know if you have any more questions. (This isn't my day job, but it is what my graduate degree is in.)

I eat foods that are high on the GI index like white rice nearly everyday and I have <12% bf. I also workout 3x a week and play sports 3 times a week so I get plenty of activity in. It really depends how active you are and how high your metabolism is. Look at Phelps, the guy swims like a madman so it allows him to eat like a madman too.

Yeah, spot fat burning is bogus. However, spot muscle toning is obviously f'reals: that's what bodybuilding is, as typical abs exercises are, in fact, spot toners for your abdomenal muscles.

Two things look shitty: A six pack set of abs surrounded by fat (yeah, there's fat under and on top of your ab muscles); and an abdomen that has little or no fat, but has no muscle tone to keep the core in place (ie a skinny person with a pot belly and fucked up little love handles). So, to do it right, you have to take a general approach to burning body fat while doing targeted exercises to strengthen your abdomenal muscles. Do not dismiss the standing dumbell side crunch as a good way to tighten up those sides. And cable crunches are great if you hate doing floor ab routines.

+1 on spot toning. Everyone has a different spot where they lose fat first. My stomach, then Face.

I dont think spot toning is possible...

In terms of diet, reduce your intake of carbs and increase your intake of protein. In terms of exercise, keep your heart rate between 65% and 89% of your max and keep the effort up for 25 minutes or longer to burn fat stores in your body. Remember, slow and steady wins the fat loss race!

I couldn't agree more. Slow and steady is the key to getting your body to where you want it to be. I can't tell you how many friends go on a "diet" at various times of the year, working out 7 days a week and consuming 1/2 the calories that their bodies are accustomed to. I would switch up your excercises every few weeks to a month to keep your body guessing. I generally lift weights 3-4 days a week, and do cardio every other day. I keep my workouts interesting..during the summer months I'll kayak or do something more interesting than running on a hamster wheel.