I have come to understand that the better in shape you are cardiovascular-wise, the more fat your body chooses to use for energy for everyday tasks (raking leaves, mowing lawn, walking the dog, ect.). I have always taken this as simple truth, but I want to know how well founded this idea is in the medical community. I have been basing my workouts on this principle for the past 8 months or so, with great results. I just want to know exactly how this idea came to be accepted as truth… by theory or studies or both… and how widely accepted and proven it is. Just curious.
I believe it is not directly an issue with the cardiovascular system, but rather the amount of muscle. The more muscle you have just sitting there doing nothing, the more energy your body needs even if you’re not doing anything -> the more fat it will burn if you don’t provide that energy through eating. So if you go on an exercise program, and gain 20 lbs of muscle in a year(very very difficult, but possible for a newbie), and then stop exercising, you will burn fat at a higher rate than a year ago.
It’s not just an issue of the amount of muscle you have. Basically, stored fat has to be removed from storage before it can be used for fuel, and that process requires oxygen. The better cardiovascular shape you’re in, the more oxygen you can intake, and the more stored fat you can metabolize.
Of course, having muscle mass drives up your energy requirements, so you have to keep that in mind too.
Neither of you want to comment on the ratio of energy used for daily low-intensity activity (carbs:protein:fat) in a person before being in good shape and then after? 'Cause that is what the issue is here…
It would take some time to dig up cites, but yes, I believe it is fairly well-established that you use more fat for fuel when you’re in better cardiovascular shape.
So why are the last few pounds always the hardest to lose?
I’m in great physical and cardio shape. I work out very regularly and for a long time now. I find that I have to almost redouble my efforts (both gym and diet) to lose just 5 pounds.
I guess my point is, the body adapts to a certain level of fitness and goes into stasis. So while average caloric/fat burning is higher for an athlete than for a sedantery person, there is also something to be said for the body’s ability to become more efficient (economical).
To illustrate, I have a proportionately large amount of muscle compared to someone who is my height but leads a sedentary lifestyle. Somebody overweight will burn more calories despite smaller muscle mass on an eliptical trainer over the same period of time performing at the same level of intensity.
Also for all we know fat could be different from fat. Your body might be trying the hardest to hold on to those last few pounds just so you don’t starve immediately come winter.
Regardless, if you’re calorie-deficient, your metabolism will slow down. A good diet and plenty of activity mitigates that, but it doesn’t eliminate it completely.
Well, one reason is the last few pounds don’t represent excess weight from a health standpoint, they’re just pounds you’d like to lose for the sake of appearance.
I’ve got the same problem, every summer I need to lose five or six pounds to make a weight class for my sport. I’m at around 20% body fat which is nice healthy percentage but not particularly low. Losing those few pounds and lowering my body fat percentage takes a lot more concious dieting and exercise than you would think. I started last week hoping I can do it without too much pain by August…
As long as we’re on this subject, I’m having trouble keeping my waistline under control, yet I eat less, drink less alcohol, and exercise more than I did four years ago, when I bought four pairs of gabardine slacks I can no longer fasten. I suspect depressed metabolism due to age, but what’s the best way to kick that up? I always hear that one should switch to doing more cardio, but doesn’t that contradict the idea of more muscle equalling more fat consumed?
It’s important to remember that in order for your muscles to burn fat, the fat must be released from the fat cells first. The lipolysis enzymes in the fat cells that control the release of fat from the fat cells, into the blood stream, and on to the muscles, grow and get much better at releasing fat when your body is healthier. Thus, the more you exercise, the more efficiently fat can be released from your fat cells to be consumed by your muscles. The fat cells of a finely tuned athlete will begin releasing fat at the slightest physical exertion. The opposite is also true: The lipogenesis enzymes, which have the job of stockpiling fat within the fat cells, tend to get stronger in a less healthy person. Lipogenesis enzymes group bits of fat together inside the fat cell so it cannot escape. You must have strong and active lipolysis enzymes to release the fat to the muscle, otherwise you’ll burn lots of sugar and very little fat, no matter how much you exercise. That unbalanced metabolism is what results in the formation of lactic acid, and we all know what that feels like. “Feeling the burn” is a bad thing.
The best way to inhibit your liplysis enzymes? Eat a lot of sugar before you exercise. The sugar stimulates your pancreas, which releases insulin. The insulin blocks the action of the lipolysis enzymes, and then your muscles run out of fat to burn, and then you don’t run anymore.
The best way to build up your lipogenesis enzymes, and thus store lots of fat? Fasting. If you go on a fast for a few days, your lipogenesis enzymes go into a panic because they think your body is in the middle of a famine. So the lipogenesis enzymes grow bigger, ready to store as much fat as they can when the time comes. So when you do finally eat something, you’ll pack away more fat than you ever would have before. Ah, biochemical irony…
So in order to reverse or mitigate the process… IOW… to strengthen the lipolysis enzymes to extract the fat and weaken/reduce the fat holding ability of the lipogenesis enzymes, we need to do what?